Camus Hydronics VTech Series Manual

6226 Netherhart Road, Mississauga, ON L5T 1B7 99-0234 –Rev 00
VTech™Series
Installation and Service Manual
Storage Type Domestic Hot Water Heater: Models 80 to 499
WARNING
If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal
injury or death.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance,
Do not touch any electrical switch; do not use any phone in your building,
Immediately call your gas supplier from a neighbour’s phone. Follow the gas supplier’s instructions,
If you cannot reach your gas supplier, call the fire department.
A Qualified installer, service agency or the gas supplier must perform installation and service.
WARNING
Do not store or use gasoline or other flammable vapours and liquids in the vicinity of this or any other appliance.
TO THE INSTALLER: After installation, these instructions must be given to the end user or left on or near the appliance.
TO THE END USER: This booklet contains important information about this appliance. Retain for future reference.

1

6226 Netherhart Road, Mississauga, ON L5T 1B7 99-0234 –Rev 00
Table of Contents
Part 1 –General Information.................................................. 1
1.1 –Special Instructions to Owner..............................................1
1.2 –Product Overview .................................................................1
1.3 –Product Ratings....................................................................2
1.3.1 –Dimensions, Connections and Weight .............................2
1.3.2 –Performance, Storage and Electrical Ratings..................3
1.3.3 –First Hour Recovery...........................................................3
1.3.4 –Continuous Recovery........................................................3
1.4 –Sequence of Operation.........................................................4
1.5 –Codes.....................................................................................4
1.6 –Warranty................................................................................4
1.7 –Scald Prevention...................................................................4
Part 2 –Installation................................................................. 4
2.1 –Checking the Equipment......................................................4
2.2 –Mechanical Environment......................................................5
2.2.1 –Freeze Protection...............................................................5
2.3 –Locating the Equipment .......................................................5
2.4 –Clearances.............................................................................5
2.5 –Condensate Removal and Treatment ..................................6
2.6 –Insulation...............................................................................6
2.7 –Pump Assembly....................................................................6
Part 3 –Venting & Combustion Air ....................................... 7
3.1 –General Venting Guidelines .................................................7
3.1.1 –Venting Transition..............................................................7
3.1.2 –Vent Drainage.....................................................................7
3.1.3 –CAT II Venting ....................................................................8
3.1.4 –CAT IV Venting...................................................................8
3.1.5 –Venting Materials ...............................................................9
3.2 –General Combustion Air Guidelines....................................9
3.2.1 –Direct Combustion Air Supply ..........................................9
3.2.3 –Combined Combustion Air Supply.................................10
3.2.3 –Room Combustion Air Supply ........................................10
3.3 –Installation and Termination ..............................................11
3.3.1 –Vertical Configuration Guidelines...................................11
3.3.2 –Sidewall Configuration Guidelines .................................12
3.3.3 –Sidewall Clearance Specifications..................................14
3.4 –Removal of Existing Appliance (If Applicable)..................15
3.5 –Outdoor Venting..................................................................15
Part 4 –Gas and Combustion Hardware............................. 16
4.1 –Gas Piping and Connections .............................................16
4.2 –Gas Supply Pressure..........................................................16
4.2.1 –Gas Regulators and Lockup Pressure............................16
4.3 –Air/Gas Ratio Control Valve ...............................................16
4.4 –Gas Pressure Switches ......................................................17
4.4.1 –Low Gas Pressure............................................................17
4.4.2 –High Gas Pressure...........................................................17
4.5 –Air Pressure Switches........................................................17
4.5.1 –Blocked Flue Switch........................................................17
4.5.2 –Low Air Switch.................................................................17
4.6 –Combustion Air Blower ......................................................17
4.7 –Burner..................................................................................17
4.8 –Ignition System...................................................................18
4.8.1 –Hot Surface Igniter (Glow Bar)........................................18
4.8.2 –Flame Sensor...................................................................18
Part 5 –Water........................................................................ 19
5.1 –Installation Guidelines........................................................19
5.2 –Connecting to the Tank......................................................19
5.3 –Hydraulic Safeties...............................................................19
5.3.1 –Low Water Cut-off (LWCO)..............................................19
5.3.2 –High Limit.........................................................................20
5.5 –Expansion Tank ..................................................................20
Part 6 –Electrical.................................................................. 21
6.1 –Blower Motors.....................................................................21
6.2 –Ignition Control...................................................................21
Part 7 –VTech Control Panel............................................... 22
7.1 –Levels of Access.................................................................22
7.2 –VTech Touchscreen Display ..............................................22
7.3 –Lockout/Alert Condition .....................................................22
7.3.1 –Manual Reset Codes........................................................23
7.3.2 –Automatic Reset Codes...................................................23
7.4 –Control Menus.....................................................................24
7.4.1 –View Menu (Read-Only) ...................................................24
7.4.2 –Setup Menu ......................................................................25
7.4.3 –Monitor Menu ...................................................................25
7.4.4 –Time Menu........................................................................26
7.4.5 –Toolbox Menu...................................................................27
7.4.6 –Source Menu....................................................................28
7.4.7 –Manual Override Menu.....................................................30
Part 8 –Commissioning/Start-up ........................................ 31
8.1 –Checking the Installation....................................................31
8.2 –Checking Gas Supply Pressure.........................................31
8.3 –Combustion Setup..............................................................31
8.3.1 –Adjust Low Fire Setting...................................................31
8.3.2 –Adjust High Fire Setting ..................................................32
8.3.3 –Flame Monitoring.............................................................32
8.4 –Final Commissioning..........................................................32
Part 9 –Service/Maintenance............................................... 33
9.1 –Examine the Venting System –Annual .............................33
9.2 –Combustion Air Blower –Annual ......................................33
9.3 –Burner Maintenance –Annual............................................33
9.3.1 –Burner Removal...............................................................33
9.3.2 –Burner Cleaning –As Required ......................................33
9.5 –Check the Condensate Neutralizer –6 Months..................34
9.6 –Draining and Flushing –Annual ........................................34
9.7 –Complete the Service..........................................................34
9.8 –Troubleshooting..................................................................34
9.8.1 –Flow Diagrams .................................................................35
Appendix A –Electrical Schematics ................................... 38
Appendix B –Parts –Exploded View.................................. 39

1
Part 1 – General Information
1.1 –Special Instructions to Owner
This manual supplies information for the installation, operation and servicing of the appliance. It is strongly recommended that this
manual be reviewed completely before proceeding with an installation.
NOTE: RETAIN THIS MANUAL FOR FUTURE REFERENCE
WARNING
It is important that all gas appliances are installed by a qualified installer/technician that is trained by CAMUS Hydronics. It is in
your own interest and that of safety to ensure that all local codes, and all the following “NOTES”, “CAUTIONS”, and “WARNINGS”
are complied with. Installing, servicing or adjusting this appliance should be performed only by a qualified installer/technician that
is trained by CAMUS Hydronics. The technician must utilize a combustion analyzer with CO2, CO, and draft gauge, to set the
appliance according to CAMUS Hydronics’ recommendations, prior to commissioning.
WARNING
To minimize the possibility of serious personal injury, fire or damage to your appliance, never violate the following safety rules
WARNING
IMPROPER INSTALLATION, ADJUSTMENT, ALTERATION, SERVICE OR MAINTENANCE can cause injury or property
damage. Refer to this manual. For additional information, consult a qualified installer, service agency or gas supplier.
WARNING
Should overheating occur or the gas supply fails to shut off, shut off the gas supply at a location external to the appliance.
DO NOT
Do not use this appliance if any part of it has been under water. The possible damage to a flooded appliance can be extensive
and present numerous safety hazards. Any appliance that has been under water must be replaced.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance. • Do not touch any electric switch: do not use any phone in your building. • Immediately call your
gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions. • If you cannot reach your gas supplier, call the fire
department.
IMPORTANT
Consult and follow local Building and Fire Regulations and other Safety Codes that apply to this installation. Contact the local
gas utility company to authorize and inspect all gas and flue connections. Installation and service must be performed by
CAMUS qualified factory trained service technicians.
Water heaters are heat producing appliances. To avoid damage or injury, do not store materials against the appliance or the vent-
air intake system. Use proper care to avoid unnecessary contact (especially children) with the appliance and vent-air intake
components.
Never cover your appliance, lean anything against it, store trash or debris near it, stand on it or in any way block the flow of fresh
air to your appliance.
UNDER NO CIRCUMSTANCES may flammable materials such as gasoline or paint thinner be used or stored in the vicinity of this
appliance, vent-air intake system or any location from which fumes could reach the appliance or vent-air intake system.
A gas appliance that draws combustion air from the equipment room where it is installed must have an adequate supply of fresh
air circulating around it during burner operation for proper gas combustion and proper venting.
1.2 –Product Overview
The VTech is a condensing, direct fired, forced draft water heater with a fully passivated stainless steel storage tank. It is designed
for use with a fully pressurized domestic hot water system, at working pressures up to 160 PSI. The water heater will automatically
modulate to provide heat outputs between 100% and 20% of maximum design. Modulation rate is determined by the built-in digital
control according to current load demands.
The VTech utilizes a premix power burner based on a push-through design, which offers several venting options. Fuel input is
controlled by a one-to-one air/gas ratio gas valve. The operation of the blower generates a negative pressure that varies according
to the current rate of modulation and current combustion air density. The gas control valve will match this pressure on the gas side,
ensuring air and gas are metered in precise proportion (1:1 ratio). Steady state efficiency is maintained across the entire range of
modulation, because the combustion characteristics which determine efficiency remain the same. The gas valve also automatically
adjusts to changes in combustion air density caused by seasonal air temperature (or altitude) differences, providing an “inherent O2
trim” correction to maintain the desired combustion settings.

2
1.3 –Product Ratings
1.3.1 –Dimensions, Connections and Weight
ALL DIMENSIONS IN INCHES
***All units have 1 1/2" Water Connections and 1” Temperature & Pressure Relief Valve Connection***
Model
"A"
"B"
"C"
"D"
"E"
"F"
"G"
"H"
"J"
"K"
Diameter of
Vent/Intake Pipe
CAT II
Air
Inlet
Ø Gas
Inlet
(NPT)
Ship
Weight
(lbs.)
25ft to
100ft
15ft to
25ft
Up to
15ft
0080
53
27
41
11 3/4
49 1/2
11 1/2
48
41
7 1/4
4 1/2
3
3
2
4
2
1/2
465
0100
53
27
41
11 3/4
49 1/2
11 1/2
48
41
7 1/4
4 1/2
3
3
2
4
2
1/2
465
0125
66
27
54
11 3/4
62 1/2
11 1/2
61
54
7 1/4
4 1/2
3
3
2
4
2
1/2
520
0150
66
27
54
11 3/4
62 1/2
11 1/2
61
54
7 1/4
4 1/2
3
3
2
4
2
1/2
520
0199
76
27
64
11 3/4
72 1/2
11 1/2
71
64
7 1/4
4 1/2
3
3
2
4
2
1/2
648
0250
76
27
64
11 3/4
72 1/2
11 1/2
71
64
7 1/4
4 1/2
3
3
2
4
2
1/2
739
0299
76
27
64
11 3/4
72 1/2
11 1/2
71
64
7 1/4
4 1/2
4
3
3
5
3
3/4
752
0399
76
27
64
11 3/4
72 1/2
11 1/2
71
64
7 1/4
4 1/2
4
3
3
5
3
1
752
0499
85 3/4
27
73 3/4
11 3/4
80 3/4
11 1/2
80 3/4
73 3/4
7 1/4
4 1/2
4
3
3
6
3
1
845

3
1.3.2 –Performance, Storage and Electrical Ratings
Model
Input
[Btu/h]
Output
[Btu/h]
Minimum Input
[Btu/h]
Tank Capacity
[US GAL.]
Tank Capacity
[LITERS]
Electrical
Full Load Amps*
0080
80,000
76,000
16,000
60
227
5.7
0100
100,000
95,000
20,000
60
227
5.7
0125
125,000
118,750
25,000
80
302
6.3
0150
150,000
142,500
30,000
80
302
6.3
0199
199,000
189,050
40,000
100
378
6.6
0250
250,000
237,500
50,000
100
378
6.6
0299
299,000
284,050
60,000
100
378
8.9
0399
399,000
379,050
80,000
100
378
8.9
0499
499,000
474,050
100,000
115
435
9.6
*Provide 15amp over current protection.
1.3.3 –First Hour Recovery
Model
140oF
Rise
GPH
78oC
Rise
LPH
120oF
Rise
GPH
67oC
Rise
LPH
100oF
Rise
GPH
56oC
Rise
LPH
80oF
Rise
GPH
44oC
Rise
LPH
60oF
Rise
GPH
33oC
Rise
LPH
40oF
Rise
GPH
22oC
Rise
LPH
0080
125
473
136
515
151
571
174
659
212
802
288
1090
0100
141
534
155
587
174
659
202
765
250
946
345
1306
0125
182
689
199
753
222
840
258
977
317
1200
436
1650
0150
202
765
222
840
251
950
293
1109
365
1382
507
1919
0199
262
992
289
1094
327
1238
383
1450
478
1809
667
2525
0250
303
1147
337
1276
385
1457
456
1726
575
2177
812
3074
0299
343
1298
384
1454
440
1665
525
1987
668
2527
951
3600
0399
425
1609
479
1813
554
2097
668
2529
857
3244
1236
4679
0499
521
1972
589
2230
683
2585
826
3127
1062
4020
1536
5814
1.3.4 –Continuous Recovery
Model
140oF
Rise
GPH
78oC
Rise
LPH
120oF
Rise
GPH
67oC
Rise
LPH
100oF
Rise
GPH
56oC
Rise
LPH
80oF
Rise
GPH
44oC
Rise
LPH
60oF
Rise
GPH
33oC
Rise
LPH
40oF
Rise
GPH
22oC
Rise
LPH
0080
65
246
76
288
91
344
114
431
152
575
228
863
0100
81
307
95
360
114
431
142
537
190
719
285
1079
0125
102
386
119
450
142
537
178
674
237
897
356
1348
0150
122
462
142
537
171
647
214
810
285
1079
427
1616
0199
162
613
189
715
227
859
283
1071
378
1431
567
2146
0250
203
768
237
897
285
1079
356
1348
475
1798
712
2695
0299
243
920
284
1075
341
1291
426
1613
568
2150
851
3221
0399
325
1230
379
1435
454
1718
568
2150
757
2865
1136
4300
0499
406
1537
474
1794
568
2150
711
2691
947
3585
1421
5379

4
1.4 –Sequence of Operation
1. Supply power connection as per Section 1.3.2.
2. The power switch is placed in the “ON” position. 120 VAC
power is supplied to the control transformer. 24 VAC is
supplied to the ignition module and low voltage controls for
all models.
3. If a Low Water Cut-off (LWCO) is supplied, it must be closed
to allow operation. The LWCO is to be wired into the
appropriate contacts on the unit control panel.
4. The control activates the unit when the temperature
measured by the top tank sensor drops below the setpoint
(“SETPOINT”) by the programmed tank differential (“DIFF
ON”).
5. The control energizes the blower, increasing the voltage to
the electrically commutated DC motor on the combustion fan.
6. If the airflow switches are closed the fan will run at pre-purge
speed until the pre-purge timer is satisfied.
7. After pre-purge, the control will target the ignition fan speed.
8. The control energizes the hot surface igniter for about 10
seconds. At the end of this period, the main gas valve is
energized for 4 seconds, during which time the flame must be
established.
9. The hot surface igniter is de-energized at the end of the
ignition period.
10.At the end of the flame establishing period, a signal of 0.8 Vdc
must be recognized by the controller at the flame sensor
(“CURRENT”) to keep the main gas valve in an open position.
The fan is kept at ignition speed until the stabilization timer is
satisfied, and the main flame is established.
11.The control will enter operation and release to modulation.
12.The control will modulate fan speed through Pulse Width
Modulation (PWM), adjusting water heater input to meet and
then maintain target temperature.
13.Fan speeds will modulate down when the temperature
measured by the temperature sensor is approaching setpoint.
14.The control will stage the unit off when the temperature
measured by the top tank sensor reaches setpoint.
15.The burner will shut off and the fan speed will ramp up to
post-purge speed until the post-purge timer is satisfied.
16.The unit will then go into standby until the next demand.
1.5 –Codes
The equipment shall be installed in accordance with those
installation regulations in force in the local area where the
installation is to be made. These shall be carefully followed in
all cases. Authorities having jurisdiction shall be consulted before
installations are made. In the absence of such requirements, the
installation shall conform to the latest edition of the National Fuel
Gas Code, ANSI Z223.1. NFPD 54 and/or CSA B149.1-15 and
CSA B149.2-15 Natural Gas and Propane Installation Code. All
electrical wiring must be done in accordance with the
requirements of the authority having jurisdiction or, in the
absence of such requirements, with National Electrical Code,
ANSI/NFPA70 and/or the Canadian Electrical Code part 1 CSA
C22.1. Where required by the authority having jurisdiction, the
installation must conform to American Society of Mechanical
Engineers Safety Code for Controls and Safety Devices for
Automatically Fired Boilers, ASME CSD-1. All water heaters
conform to the latest edition of the ASME Boiler and Pressure
Vessel Code, Section II. Where required by the authority having
jurisdiction, the installation must comply with the CSA
International, CSA B149.1-15 and CSA B149.2-15 and/or local
codes. This appliance meets the safe lighting performance
criteria with the gas manifold and control assembly provided, as
specified in the ANSI standards for gas-fired units, ANSI
Z21.10.3.
1.6 –Warranty
Factory warranty (shipped with unit) does not apply to units
improperly installed or improperly operated.
Factory warranty (shipped with unit) does not apply to units
with no or improperly installed or operated pump assembly.
Factory warranty shall apply only when the appliance is
installed in accordance with local plumbing and building
codes, ordinances and regulations, the printed instructions
provided with it and industry best practices.
Excessive water hardness causing a scale buildup in the
stainless steel coils or tubes is not a fault of the appliance and
is not covered by warranty.
Using or storing corrosive chemicals in the vicinity of this
appliance can rapidly attack the stainless steel tubes and
coils and voids warranty.
Damage caused by freezing or dry firing voids warranty.
This appliance is not to be used for temporary service of
buildings under construction.
The manufacturer shall NOT be held liable for any personal
injury or property damage due to ice formation or the
dislodging of ice from the vent system or the vent termination.
1.7 –Scald Prevention
Water should be stored above 122°F (50°C) to avoid the bacterial
growth that happens at cooler temperatures. Bacteria won’t grow
above this level but are not destroyed, so systems often require
water be heated to 158°F (70°C) or above to kill any bacteria that
are present (140-160°F (60-71°C) is common in commercial
kitchens). This temperature causes the water to become more
aggressively corrosive, shortening the tank’s service life, so the
commonly recommended storage temperature is 140°F (60°C).
These temperatures have the potential to scald with enough
exposure time, so thermostatic mixing valves that temper water
to safe levels should be provided. Such valves are required in
some jurisdictions. Storing and mixing water to cooler levels also
increases the effective storage volume, maximizing the delivery
potential of a given tank capacity.
Temperature,
°F (°C)
Time for 1st Degree
Burn (Less Severe)
Time for 2nd or 3rd
Degree Burn
110 (43)
High-end of Normal Shower Temperatures
116 (47)
35 Minutes
45 Minutes
122 (50)
1 Minute
5 Minutes
131 (55)
5 Seconds
25 Seconds
140 (60)
2 Seconds
5 Seconds
149 (65)
1 Second
2 Seconds
154 (68)
Instant
1 Second
Part 2 – Installation
2.1 –Checking the Equipment
Check for signs of shipping damage upon receiving equipment.
Pay particular attention to the powder coat stainless finish outer
shell, which may show signs of being hit or otherwise being
mishandled. Verify total number of pieces shown on packing slip
with those actually received. In case there is damage or a
shortage, immediately notify freight carrier. Pump assembly
ships lose with the unit which needs to be installed in the field.

5
Do not attempt to pry any panel off.
If applicable, the Normally-Open dry contacts in the low water
cut-off (LWCO) are to be wired into the appropriate terminals on
the control board. Locate the probe type LWCO in the piping
above the highest point of the water heater. In all cases check
with local codes.
2.2 –Mechanical Environment
Install this appliance in a clean, dry location with adequate air
supply. Due to low jacket losses from the appliance,
temperatures in a typical mechanical room may be significantly
colder than the rest of the structure. In cases where combustion
air is being supplied into the mechanical room, the temperature
may be below freezing. Supplemental heat is sometimes
required to maintain ambient temperature at acceptable levels
and prevent freezing of various system components.
The mechanical room MUST NOT be used to store corrosive or
flammable chemicals, such as gasoline or paint thinner, which
may be harmful to the water heater, or contaminate the
combustion supply air. Such chemicals must not be stored in the
vicinity of this appliance, the vent termination, or combustion air
intake, or any location from which fumes could reach the
appliance, the vent termination, or combustion air intake. Chillers
or other equipment utilizing refrigerant should also not be
installed in the same mechanical room as fuel burning
appliances.
In cases where the mechanical environment is a concern, the
water heater should be installed as a “sealed combustion”
appliance, with combustion supply air connected directly to the
blower. Please contact the factory for more information on this
installation method.
2.2.1 –Freeze Protection
Freezing is less of a concern with a tank type water heater than
with some other equipment, as the unit will fire when the stored
water volume begins to cool. However, since the unit can be
manually deactivated, installations are still not recommended in
areas where the danger of freezing exists. Proper freeze
protection (i.e. a supplemental heat source dedicated to the
mechanical space) must be provided for appliances installed in
unheated mechanical rooms or where temperatures may drop to
the freezing point or lower. If freeze protection is not provided for
the system, a low ambient temperature alarm is recommended
for the mechanical room. Damage to the appliance by freezing is
not covered under warranty.
Water heaters must be located in a room with a consistent
temperature of at least 50ºF (10ºC).
CAUTION
A mechanical room operating under a negative pressure may
experience a downdraft in the flue of an appliance that is not
firing. The cold outside air may be pulled down the flue and
freeze a heat exchanger. This condition must be corrected to
provide adequate freeze protection.
Appliance installations are not recommended outdoors in areas
where danger of freezing exists. Precautions can be taken to
protect the appliance from damage.
If for any reason, the unit is to be shut off where danger of
freezing exists, the following precautionary measures must be
taken:
Shut off gas supply
Shut off water supply
Shut off electrical supply
Drain the water heater and connecting piping completely.
2.3 –Locating the Equipment
The appliance should be located close to a floor drain in an area
where leakage from the appliance or connections will not result
in damage to the adjacent area or to lower floors in the structure.
Under no circumstances is the manufacturer to be held
responsible for water damage in connection with this unit, or any
of its components. The appliance must be installed so that the
ignition system components are protected from water (dripping,
spraying, etc.) during appliance operation and service (circulator
replacement, control replacement, etc.).
If the appliance is installed above the level of the building’s
distribution system, a low water cut-off device may be required
above the heat exchanger inlet/outlet connections. Some local
codes require the installation of a low water cut-off on all
systems. Please check with the authority having jurisdiction.
Appliances located in a garage and in adjacent spaces that open
to the garage and are not part of the interior space must be
installed so that all burners and burner ignition devices have a
minimum clearance of not less than 18" (46cm) above the floor.
The appliance must be located or protected so that it is not
subject to physical damage by a moving vehicle.
DO NOT install this appliance in any location where gasoline
or flammable vapors are likely to be present.
If the appliance is to be installed near a corrosive or
potentially corrosive air supply, the appliance must be
isolated from it and outside air should be supplied as per
code. Potentially corrosive atmospheres will result from
exposure to permanent wave solution,chlorinated waxes and
cleaners, chlorine, water softening chemicals, carbon
tetrachloride, halogen based refrigerants, Freon cleaning
solvents, hydrochloric acid, cements and glues, masonry
washing materials, antistatic fabric softeners, dry cleaning
solvents, degreasing liquids, printing inks, paint removers,
etc.
DO NOT install this appliance on top of carpet flooring. The
appliance must be installed on a level floor. Maintain required
clearances from combustible surfaces.
Every VTech is designed for either indoor installation, where they
are protected from exposure to wind, rain and weather, or
outdoor installation (by using special kit). Always consider the
use of a shelter such as a garden shed in lieu of direct exposure
of the appliance to the elements when installed outdoors. The
additional protection afforded by the shelter will help to minimize
nuisance problems with electrical connections and will allow
easier servicing of the appliance under severe weather
conditions.
2.4 –Clearances
This appliance is suitable for alcove (a closet without a door)
installation with minimum clearances to combustibles as follows:

6
Table 1: Clearances From Combustibles
All Models
Top/Rear
0"
(0cm)
Front
6"
(15cm)
Sides
0"
(0cm)
Vent
1"
(2.5cm)
Table 2: Recommended Service Clearances
All Models
Top
Right Side
Left Side
Back
Front
24” (60cm)
12” (30cm)
12” (30cm)
12” (30cm)
12” (30cm)
Clearances from combustible construction are noted on the
appliance rating plate. When installed directly on combustible
flooring, the appliance shall be installed on a metal panel
extending beyond the full width and depth of the appliance by at
least 3 inches (76.2mm) in any direction. The floor must be strong
enough to support the full weight of the heater. When placing the
appliance be aware that a minimum clearance of 24” (60cm)
must be provided at the front to allow easy access to the heat
exchanger. A service clearance of 24” must be provided above
the top panel to allow access to the burner. Maintain specified
clearances for adequate operation. All installations must allow
sufficient space for servicing the vent connections, water pipe
connections, circulating pump, bypass piping and other auxiliary
equipment, as well as the appliance.
2.5 –Condensate Removal and Treatment
This high efficiency appliance operates in a condensing mode
due to the low temperatures of incoming water supply.
Condensate occurs when the products of combustion are cooled
below their dew point in the heat transfer process. The liquid
condensate formed from this high efficiency heat transfer
process is mildly acidic. The condensate will typically have a pH
ranging from 3.5 to 5.0 as it is discharged from the condensate
drain at the rear of the appliance. Many codes will require
neutralization before it can be piped to a drain system.
Neutralization is recommended with every appliance.
The neutralizer consists of an industrial grade, non-corrosive
reservoir for collection of the condensate, filled with a
consumable fill media that raises the pH of the water. As the
reservoir fills, it provides an extended residency time to neutralize
the condensate. As the pH number increases in numerical value,
the relative acidity of the discharge decreases. The neutralized
condensate may then be discharged into a suitable drain system
without fear of damaging the drain piping. Condensate must be
able to flow freely from the appliance. Condensate flow is
accomplished by gravity, requiring a minimum downward slope
of 1/4” per foot (21mm/m) to ensure proper flow to the neutralizer
and/or a suitable drain. The neutralizer MUST always be
mounted on the same level or lower than the condensate drain
at the vent connection.
The VTech and vent condensate drain requires a trap of some
kind upstream of the neutralizer, to ensure that flue gas does not
exit through the drain (this must be provided external of the water
heater). Prime the trap with water during commissioning. Use
standard ½" vinyl, PVC, CPVC or suitable hose to run to floor
drain. Neutralizers may be used in series to raise pH. See
Section 3.1.2 for more information on proper drainage of
condensate.
Always check with local codes for specific pH requirements. All
condensate piping and connections must be easily accessible for
routine maintenance and inspection.
2.6 –Insulation
The VTech incorporates a foam insulation around the storage
tank, underneath the outer shell. No additional insulation is
required. If additional insulation is used, it must not extend
beyond lower edge of the top dome of the water heater (i.e. it
must not cover any portion of the top of the water heater, which
could obstruct air flow and restrict serviceability).
2.7 –Pump Assembly
The pump assembly (ships loose with the water heater) needs to
be installed on all installations. The pump assembly can be
installed either on right or left side fof the unit depending on
where the water connections are. Refer to Appendix B on how
to install the pump assembly.
Installation of pump assembly would help to reduces the build-up
of scale, improves efficiency by creating more contact between
the heating surfaces and the water and improves performance
by equalizing tank temperature.
Factory warranty does not apply to units with no pump assembly
installed or improperly installed or operated pump assembly.

7
Part 3 – Venting & Combustion
Air
3.1 –General Venting Guidelines
All vent installation should follow the instructions of the venting
supplier. Insulation on vent runs is not recommended, and may
not be permitted for some materials.
WARNING
These venting instructions MUST be carefully followed.
Failure to do so can cause substantial property damage,
severe personal injury, or death.
WARNING
Use of cellular core PVC (ASTM F891), cellular core CPVC or
Radel (polyphenosulfone) in venting systems shall be
prohibited.
Gas burning appliances are divided into four categories based
on the pressure and temperature produced in the exhaust stack
and the likelihood of condensate production in the vent.
Category I. An appliance operating with a non-positive vent
static pressure and with a vent gas temperature that avoids
excessive condensate production in the vent (i.e. “B Vent”).
Category II. An appliance operating with a non-positive vent
static pressure and with a vent gas temperature that may
cause excessive condensate production in the vent.
Category III. An appliance operating with a positive vent
pressure and with a vent gas temperature that avoids
excessive condensate production in the vent.
Category IV. An appliance operating with a positive vent
pressure and with a vent gas temperature that may cause
excessive condensate production in the vent (i.e. “BH Special
Gas Vent”).
The VTech water heater can be vented as either a Category II or
IV appliance. It must be vented and supplied with combustion
and ventilation air as described in this section. Provisions for
combustion and ventilation air are to be in accordance with the
section “Air for Combustion and Installation”, of the National
Fuel Gas Code, ANSI Z223.1/NFPA 54, or clause 8.2, 8.3, 8.4
of “Natural Gas and Propane Installation Code”, CSA
B149.1-15 and CSA B149.2-15, or appliance provisions of the
local building codes. The distance of the vent terminal from
adjacent buildings, windows that open and building openings
must comply with the latest edition of the National Fuel Gas
Code, ANSI Z223.1. In Canada, the installation and clearances
must comply with the latest edition of CSA B149.1-15 and CSA
B149.2-15 Installation Code for Gas Burning Appliances and
Equipment.
For indoor installations, venting must be in accordance with Part
7 “Venting of Equipment” of the National Fuel Gas Code,
ANSI Z223.1, or Section 7 “Venting of Equipment and Air
Supply for Appliances” of the CSA B149.1-15 and CSA
B149.2-15 installation code, or applicable provisions of the local
building codes. Horizontal runs of vent pipe shall be securely
supported (approximately every 4 feet) to prevent sagging and
maintain a minimum slope of ¼" per foot to provide drainage of
the vent towards the nearest drain or the vent termination.
The weight of the venting system must not rest on the unit.
Adequate support of the venting system must be provided in
compliance with local codes and other applicable codes. Vent
connection is made directly to the flue outlet opening on the back
of the unit. All connections should be secured and sealed per the
vent manufacturers specifications. When a positive vent system
is disconnected for any reason, the flue must be reassembled
and resealed according to the vent manufacturer’s instructions.
Do not use an existing chimney as a raceway if another appliance
or fireplace is vented through the chimney.
3.1.1 –Venting Transition
All VTech have a round stainless steel vent connection suitable
for direct connection to PVC or CPVC piping, of the size listed in
Section 1.3.3.
Adaptors for stainless steel venting are available from CAMUS.
Polypropylene vent adaptors are available from the venting
manufacturer directly.
Depending on the venting category chosen and the design
provide by the vent manufacturer, an increaser may be required
for the proper vent configuration.
3.1.2 –Vent Drainage
Care must be taken to properly seal all joints against leakage of
exhaust or condensate. All horizontal runs should be provided
with a slope or ¼” per linear foot to ensure efficient drainage of
condensate. This slope should be designed to take condensate
away from the water heater, and towards the nearest vent drain.
The bottom of any vertical vent run should have a combination
45°tee/elbow with drain cap installed to remove condensate in
this area of the vent. If this vertical run includes several horizontal
or angled offsets, all components must be arranged to provide a
continuous downward slope to the tee at the base of the run.
Horizontal sections from this tee must be sloped away, either to
the next tee in the system, or back to the water heater.
NOTE: Any drain in the venting system will require a trap to
ensure flue gas does not enter the interior space.
Combination Tee and Elbow, w/ Drain Cap
In systems where the vent remains horizontal after the initial
vertical rise from the water heater vent connection, it should be
sloped to drain through the sidewall. In cases where the

8
condensate cannot be drained outside, a horizontal drain section
should be installed in the venting before penetrating the sidewall.
The water heater connects directly to a vertical vent run and does
not require a base tee. A drain line must be connected to the
water heater to collect and dispose of condensate.
Drain and Neutralizer Cartridge Installation
Plastic drain tubing shall be provided as a drain line for the water
heater condensate drain. The tubing must have a trap (a 4"
(10cm) diameter circular trap loop inthe drain tubing is sufficient).
Prime the trap loop by pouring a small quantity of water into the
drain hose before assembly to the water heater connection. Use
caution not to collapse or restrict the condensate drain line. The
drain must be routed to the condensate neutralization system or
a suitable drain for disposal of condensate that occurs in both the
water heater and in the vent system. Ensure that the drain from
the condensate tee is not exposed to freezing temperature.
3.1.3 –CAT II Venting
A Category II venting system operates with a negative pressure
in the vent at all times, and with flue gas temperatures
sufficiently cool for condensation to occur before reaching the
termination. As a result, a corrosion resistant stainless steel,
such as AL29-4C or 316L, must be used for the venting. AL29-
4C is typically recommended for having higher corrosion
resistance. (This recommendation does not supersede local
codes or the provisions of CSA B149.1-15 and CSA B149.2-
15 in Canada or the National Fuel Gas Code in the United
States.) 316L is limited to use in applications where there is no
possibility of contaminants in the air such as refrigerants, chlorine
etc. Always choose the venting system which best satisfies the
requirements of the application.
The Category II vent systems can be used for single appliances,
but they can also be used to vent multiple appliances combined
into a common vent. This special venting system must be
engineered by a venting manufacturer or other qualified
professional, using a proven vent-sizing program with
knowledge of accurate operating parameters. Approval of the
installation is at the discretion of the authority having jurisdiction.
Acceptable Breech Pressure
For CAT. II Vent Systems
˗0.05” WC to ˗0.15” WC
For Category II vent systems, the pressure at the appliance
breeching must be kept within a range of ˗0.05” WC to ˗0.15”
WC. If the calculated draft at any unit exceeds this range (i.e. ≤
˗0.16” WC), a single acting barometric damper, or suitable
alternative draft control approved by the vent designer or
engineer, must be used to prevent the extra suction from
decreasing the pressure at the breeching.
If the vent cannot support a negative draft under all conditions,
and a positive pressure will be developed during some operation,
then the vent design must be changed accordingly. Possible
options include changing the design to Category IV, or providing
an extractor (or “draft inducer”) at the vent outlet, interlocked with
the appliance operating circuit, in order to maintain a negative
draft in the vent while the unit is operating. The designer must
ensure that the solution utilized will maintain the vent system at
the desired minimum draft under all conditions.
Category II vents typically terminate vertically through the roof.
The flue from a Category II vent system must have a condensate
drain with provisions to properly collect, neutralize and dispose
of any condensate that may occur.
3.1.4 –CAT IV Venting
The Category IV venting system operates with positive pressure
at the appliance breeching generated by the combustion air fan,
which operates the combustion process and also exhausts the
flue products from the building. The pressure may be positive
throughout, though it is conceivable to operate with negative
pressure in part of a Category IV vent system. In either case, the
entire Category IV vent system must have all joints and seams
sealed gas-tight. The flue products in the vent system will be
cooled below their dew point and form condensate, so Category
IV systems must use AL29-4C or 316L stainless steel, or
approved thermoplastics like UL/ULC S636 PVC or CPVC, and
polypropylene (PPE, to maximum 12” diameter).
Acceptable Breech Pressure
For CAT. IV Vent Systems
+0.01” WC to +1.00” WC
The installed length of the positive pressure Category IV vent,
from the appliance to the point of termination outside of the
building, must not exceed a maximum of 100 equivalent feet
(30.5M) in length. The straight length that each elbow equates
to depending on the diameter and centerline radius, typically 7 to
19 feet per 90° elbow and roughly half this value for each 45°
elbow. The equivalency values must be verified with the
individual vent manufacturer, as they are not standard, and
depend on the precise dimensions, surface roughness, etc., that
a particular product is built with. For site conditions exceeding
100 equivalent feet an engineered vent system approved by the
local authority will be required.
Category IV vents may terminate either vertically through the
roof, or horizontally on a side wall. See the information about the
specific vent termination location for recommended location and
clearances. The flue from a Category IV vent system must have
a condensate drain with provisions to properly collect, neutralize
and dispose of any condensate that may occur.

9
3.1.5 –Venting Materials
When selecting vent material take into consideration that
appliances installed near a corrosive or potentially corrosive air
supply must be isolated from it or they will suffer damage to the
appliance and the venting system. The VTech may be vented
with the following manufactured products:
Manufactured prefabricated UL/ULC listed vents of AL29-4C,
single or double wall.
316L stainless steel in applications free of contaminants like
refrigerants, chlorine, etc.
In Canada, the following plastic vent materials can be used,
if permitted by local jurisdictions:
oUL/ULC S636 approved schedule 40 PVC
oUL/ULC S636 approved schedule 80 PVC
oUL/ULC S636 approved schedule 40 CPVC
oUL/ULC S636 approved schedule 80 CPVC
oUL/ULC S636 approved polypropylene (PPE)
In the US, the following plastic vent materials can be used, if
permitted by local jurisdictions:
oANSI/ASTM D2665 approved PVC-DWV
oANSI/ASTM D1785 approved PVC Schedule 40
oANSI/ASTM F441 approved CPVC Schedule 40
oUL/ULC S636 approved schedule 40 PVC
oUL/ULC S636 approved schedule 80 PVC
oUL/ULC S636 approved schedule 40 CPVC
oUL/ULC S636 approved schedule 80 CPVC
oUL/ULC S636 approved polypropylene (PPE)
WARNING
Use of cellular core PVC (ASTM F891), cellular core CPVC or
Radel (polyphenosulfone) inventing systems is prohibited
Covering non-metallic vent pipe and fittings with thermal
insulation is prohibited
Stainless steel venting can be ordered as single or double wall,
depending on the installation. Double wall is recommended on
Category II installations to ensure flue gas stay buoyant enough
to maintain draft. Double wall is also recommended anywhere
the vent may be contacted by personnel operating in the
mechanical room.
Vent Material
Maximum Flue
Temperature, °F
PVC
149
CPVC
194
Polypropylene (PPE)
230
316L Stainless
+300*
AL29-4C Stainless
+300*
*Stack is limited only by the allowable temperature rating of the
gas tight seals.
Always follow local codes when venting this appliance into a
masonry chimney. A standard masonry chimney must NOT be
used to vent the products of combustion from a positive pressure
appliance, or any condensing appliances, whether positive or
negative pressure (Category II, III or IV). As the VTech is a high
efficiency appliance, if a masonry chimney is to be used, it must
be used as a raceway for installation of a sealed, corrosion
resistant liner system. Chimney liner systems are typically made
from a high grade of corrosion resistant stainless steel such as
AL29-4C or equivalent. The corrosion resistant liner must be
properly sized and fully sealed throughout the entire length. Both
the top and the bottom of the masonry chimney must be capped
and sealed to provide adead air space around the liner contained
within. Single wall venting is typically acceptable for the liner, but
any portion of the vent located outside of the masonry chimney
raceway should be double wall design.
Consult with local code officials to determine code
requirements or the advisability of using a masonrychimney
with a sealed corrosion resistant liner system.
3.2 –General Combustion Air Guidelines
Provisions for combustion and ventilation air are to be in
accordance with the section “Air for Combustion and Ventilation”
of the National Fuel Gas Code, ANSI Z223.1/NFPA 54, or clause
8.2, 8.3, and 8.4 of “Natural Gas and Propane Installation Code”,
CSA B149.1-15 and CSA B149.2-15, or applicable provisions of
the local building codes. Combustion air can be supplied by
means of conventional venting, where combustion air is drawn
from the area immediately surrounding the appliance
(mechanical room must be positive pressure) which will require
openings in the mechanical room for fresh make-up air supply,
or with direct vent (direct vent combustion) where air is drawn
directly from the outside into the water heater jacket or blower.
Refer to the NFGC, Section 8.3 for additional information.
3.2.1 –Direct Combustion Air Supply
Direct Vent/Sealed Combustion –The combustion air can
be connected directly the blower. No filter is included; one
would only be needed if the intake termination may
occasionally ingest debris. Such a filter (supplied by others)
should be installed in an easily serviceable location.
VTech with Sealed Combustion

10
The installed length of the sidewall or vertical combustion air inlet
pipe, from the appliance to the inlet terminal outside of the
building, must not exceed a maximum of 100 equivalent feet
(30.5M) in length. The straight length that each elbow equates
to depending on the diameter and centerline radius, typically 7 to
19 feet per 90° elbow and roughly half this value for each 45°
elbow. The equivalency values must be verified with the
individual vent manufacturer, as they are not standard, and
depend on the precise dimensions, surface roughness, etc., that
a particular product is built with.
3.2.3 –Combined Combustion Air Supply
The air inlet pipes from multiple appliances can be combined in
a single common air inlet pipe if the cross-sectional area, and the
combustion air opening free area, are equal to or larger than the
total area of all air inlet pipes connected together. This exterior
opening for combustion air must connect directly to the outdoors.
Deduct the restriction in area provided by any screens, grills or
louvers installed in the common air inlet point, which can reduce
the free area by 25% to 75% based on the materials used.
Determine cross-sectional area using the equation below.
Eq. Ø = √[(d1)2+(d2)2+(d3)2+…+(dn)2]
Where,
Eq. Ø = Equivalent Total Diameter
d = Individual Pipe Diameters
Example: Find the equivalent diameter of 3x pipes
at 8" (20.3 cm), 10” (25.4 cm) and 12” (30.5 cm).
Eq. Ø = √ [(8)2+(10)2+(12)2] = √308 = 17.5”
Select 18” (82.8 cm) diameter pipe or larger
The total length of air inlet pipe for a water heater must be
calculated individually, and must not exceed amaximum 100
equivalent feet (30.5M) regardless of pipe diameter. The total
equivalent length of the common piping must be added to
equivalent length of the branch for an individual water heater. For
instance, if the common piping is 50’ (15.25M) equivalent, and
the water heater’s individual pipe branch is also 50’ (15.25M)
equivalent, this water heater is at its maximum length. The total
equivalent length of the common air inlet pipe must not
exceed a maximum of 100 equivalent feet (30.5M) under any
circumstances.
3.2.3 –Room Combustion Air Supply
All Air From Inside the Building (US Only) -If combustion
air is drawn from inside the building (the mechanical
equipment room does not receive air from outside via louvers
or vent openings and the water heater is not equipped with
direct vent combustion) and the water heater is located in a
unconfined space, use the following guidelines:
oThe mechanical equipment room must be provided with
two permanent openings linked directly with additional
room(s) of sufficient volume so that the combined volume
of all spaces meet the criteria for an unconfined space.
Note: An "unconfined space" isdefined as a space whose
volume is more than 50 cubic feet per 1,000 Btu per hour
of aggregate input rating of all appliances installed in that
space.
oEach opening must have a minimum free area of one
square inch per 1,000 Btu per hour of the total input rating
of all gas utilizing equipment in the mechanical room.
oOne opening must terminate within twelve inches of the
top, and one opening must terminate within twelve inches
of the bottom of the room.
Figure 1 –All Air From Inside, Two Openings
All Air From Outdoors, Two-Opening - If all combustion air
will be received from outside the building (the mechanical
room equipment is linked with the outdoors), the following
method can be used:
oThe mechanical equipment room must be provided with
two permanent openings, one terminating within twelve
inches from the top, and one opening terminating within
twelve inches of the bottom of the room.
oThe openings must be linked directly or by ducts with the
outdoors.
oEach opening must have a minimum free area of one
square inch per 4,000 Btu per hour of total input rating of
all equipment in the room, when the opening is directly
linked to the outdoors or through vertical ducts.
oThe minimum free area required for horizontal ducts is
one square inch per 2,000 Btu per hour of total input rating
of all the equipment in the room. The ducts should not
exceed 100 equivalent feet (30.5M) in length.
Figure 2 –All Air From Outside, Two Openings (Optional Duct)
All Air From Outdoors, One-Opening - If all combustion air
will be received from outside the building (the mechanical
room equipment is linked with the outdoors), the following
method can be used:
oOne permanent opening, commencing within 12 inches of
the top of the enclosure, shall be provided.

11
oThe equipment shall have clearances of at least 1 inch
from the sides and back and 6 inches from the front of the
appliance.
oThe opening shall directly communicate with the outdoors
and shall have a minimum free area of 1 square inch per
3000 BTU's per hour of the total input rating of all
equipment located in the enclosure, and not less than the
sum of the areas of all vent connectors in the confined
space.
Figure 3 –All Air From Outside, One Opening
3.2.4 –Exhaust Fans
Any fan or equipment which exhausts air from the equipment
room may deplete the combustion air supply and/or cause a
downdraft in the venting system. Spillage of flue products from
the venting system into an occupied space can cause a very
hazardous condition that must be immediately corrected. Sealed
combustion should be selected in cases where exhaust fans
cannot be avoided or isolated.
3.3 –Installation and Termination
3.3.1 –Vertical Configuration Guidelines
Rooftop Vent Terminations:
oRooftop vents can terminate vertically, but in areas where
heavy rainfall is projected, a rain cap should be
considered. Rain entering the venting will drain out
through the condensate removal system, but may waste
neutralizer media, so it should be avoided where possible.
oPosition terminations so they are not likely to be damaged
by foreign objects, or exposed to a build-up of snow, ice
debris, etc., which can cause a blocked flue condition.
oPosition vents away from points of roof top access (i.e.
hatches and walkways) whenever possible.
oFlue gas condensation can freeze on the vent cap
causing a blocked flue situation. Select proper diameter
piping and cap designs to avoid excessive ice build-up.
oNOTE: If the hydronic system design uses high water
temperatures, uncondensed water vapour in the flue
products will find its way into the vent, and could form
large plumes of steam at the vent termination. This is not
harmful to the water heater but can be unsightly. The
steam can also cause discoloration on exterior building
surfaces. Adjacent brick or masonry surfaces should be
protected with a rust resistant sheet metal plate.
Rooftop Combustion Air Inlets:
oA roof top air inlet consists of two 90° elbows. The first 90°
elbow is installed on the rooftop at the highest vertical
point of the air inlet pipe and turned horizontal; the second
90° elbow is screened and is installed on the horizontal
outlet of the first elbow and turned down. If a straight piece
of pipe is used between the two elbows, it should not
exceed 6" (150mm) in length. A bird screen should be
installed on the open end of the second elbow.
oCombustion air supplied from outdoors must be free of
contaminants.
oIncorrect installation and/or location of the air inlet cap can
allow flue products to be drawn back into the appliance.
This can result in incomplete combustion and potentially
hazardous levels of carbon monoxide in the flue products.
This will cause operational problems with the appliance
and if left uncorrected, will lead to conditions that can
cause personal injury or death.
Clearances:
oThe vent terminal must exhaust outside the building at
least 2 feet (0.61M) above the highest point of the roof
within a 10 foot (3.05M) radius of the termination.
oA vertical termination less than 10 feet (3.05M) from a
parapet wall must be a minimum of 2 feet (0.61M) higher
than the parapet wall.
oThe termination of the vent/air intake must be a minimum
of 3 feet (0.91M) above the roof penetration, and at least
12 inches (30cm) above the projected snow level.
oThe inlet MUST be at least 1 foot (0.3M) below the point
of flue gas termination (vent cap) if located within a 5 foot
(1.5M) radius of the flue outlet. Ensure that the 90° elbow
assembly is properly installed on the air inlet pipe.
Vertical Direct Venting Configuration
Concentric Venting - Kits can be ordered to provide venting
and combustion air supply through one opening. Vent/air pipe
still limited a maximum 100 equivalent feet (30.5M) in length.
Vertical Concentric Vent Clearances

12
3.3.2 –Sidewall Configuration Guidelines
Sidewall Vent Terminations:
oSidewall vents can terminate horizontally, but in areas
with heavy rain a downturned 45°elbow can be installed
to keep water from blowing into the opening. Rain
entering the venting will drain out through the condensate
removal system, but may waste neutralizer media, so it
should be avoided where possible.
oIn penetrating through a windward wall, a horizontally
mounted tee (i.e. with all openings on the same plane)
can be installed to reduce the effect of wind loading.
oPosition terminations so they are not likely to be damaged
by foreign objects, or exposed to a build-up of snow, ice
debris, etc., which can cause a blocked flue condition.
oDo not terminate the vent in a window well, stairwell,
alcove, courtyard or other recessed area. The vent cannot
terminate below grade.
oPosition the vent termination where vapours will not
damage walls or plants or may otherwise be
objectionable.
oThe vent outlet MUST NOT terminate below a forced air
inlet at any distance.
oNOTE: If the hydronic system design uses high water
temperatures, uncondensed water vapour in the flue
products will find its way into the vent, and could form
large plumes of steam at the vent termination. This is not
harmful to the water heater but can be unsightly and
obstruct views from windows. The steam can also cause
discoloration on exterior building surfaces. Adjacent brick
or masonry surfaces should be protected with a rust
resistant sheet metal plate.
Sidewall Combustion Air Inlets:
oSidewall combustion air inlets consist of a single 90°
elbow, installed on the end of the horizontal pipe
penetrating the wall. A bird screen should be installed on
the open end of the elbow.
oCombustion air supplied from outdoors must be free of
contaminants.
oIncorrect installation and/or location of the air inlet cap can
allow flue products to be drawn back into the appliance.
This can result in incomplete combustion and potentially
hazardous levels of carbon monoxide in the flue products.
This will cause operational problems with the appliance
and if left uncorrected, will lead to conditions that can
cause personal injury or death.
Clearances:
oThe vent terminal shall terminate at least 3 ft. (1M) above
any forced air inlet within 10 ft. (3M) horizontally.
oThe vent shall not terminate less than 7 ft. above a public
walkway due to the normal formation of water vapour in
the combustion process.
oThe vent system shall terminate at least 3 foot (1M) above
grade, or above projected snow levels.
oThe vent terminal shall not be installed closer than 3 feet
(1 m) from an inside corner of an L-shaped structure,
window well, stairwell, alcove, courtyard or other
recessed area as wind eddies could affect water heater
performance or cause recirculation.
oDO NOT terminate closer than 4 feet (1.25m) horizontally
and vertically from any electric meter, gas meter,
regulator, relief valve, or other equipment. In all cases
local codes take precedence
oPosition the vent termination where vapours will not
damage walls or plants or may otherwise be
objectionable.
oThe vent outlet MUST NOT terminate below a forced air
inlet at any distance.
oThe combustion air opening shall be at least 12” inches
(30cm) above grade, or above projected snow levels.
oThe combustion air opening should be 12” from the wall,
to remove it from the surface pressure zone.
oThe point of termination for the sidewall combustion air
inlet terminal MUST be located a minimum of 3 feet (1M)
horizontally or 12 inches (0.30M) below the point of flue
gas termination (vent cap) if it is located within a 10 foot
(3M) radius of the flue outlet.
Sidewall Vent and Air Intake - Vertical Arrangement
Sidewall Vent and Air Intake - Horizontal Arrangement

13
Concentric Venting - Kits can be ordered to provide venting
and combustion air supply through one opening. Vent/air pipe
still limited a maximum 100 equivalent feet (30.5M) in length
each.
Horizontal Concentric Vent Clearances

14
3.3.3 –Sidewall Clearance Specifications
Direct Vent Terminal Clearances
Canadian Installations1
US Installations2
A
Clearance above grade, veranda, porch, deck, or balcony
12” (30 cm)
12” (30 cm)
B
Clearance to window or door that may be opened
12” (15 cm) for appliances
<100,000 Btuh (30kW)
36” (91cm) for appliances
>100,000 Btuh (30kW)
9” (23 cm) for appliances
<50,000 Btuh (15kW)
12” (30cm) for appliances
>50,000 Btuh (15kW)
C
Clearance to window or door that may be opened
-
-
D
Clearance to permanently closed window
-
-
E
Clearance to unventilated soffit
-
-
F
Clearance to outside corner
-
-
G
Clearance to inside corner
-
-
H
Clearance to each side of center line extended above
meter/regulator assembly
3’ (91 cm) within a height of 15’
(4.5 m) above the meter/ regulator
assembly
-
I
Clearance to service regulator vent outlet
36” (91 cm)
-
J
Clearance to non-mechanical air supply inlet to building or the
combustion air inlet to any other appliance
12” (15 cm) for appliances
<100,000 Btuh (30kW)
36” (91cm) for appliances
>100,000 Btuh (30kW)
9” (23 cm) for appliances
<50,000 Btuh (15kW)
12” (30cm) for appliances
>50,000 Btuh (15kW)
K
Clearance to a mechanical air supply inlet
6’ (1.83 m)
3’ (91 cm) above if within 10’ (3
m) horizontally
L
Clearance above paved sidewalk or paved driveway located on
public property
7’ (2.13 m)α
-
M
Clearance under veranda, porch deck, or balcony
12” (30 cm)β
-
1In accordance with the current CSA B149.1-15 and CSA B149.2-15 Natural Gas and Propane Installation Code
2In accordance with ANSI Z223.1/ NFPA 54 National Fuel Gas Code
αA vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings
βPermitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
* For clearances not specified in ANSI Z223.1/ NFPA 54 or CSA B149.1-15 and CSA B149.2-15. Clearance in accordance with local installation
codes and the requirements of the gas supplier

15
3.4 –Removal of Existing Appliance (If Applicable)
When an existing appliance is removed from a common venting
system, the common venting system is likely to be too large for
proper venting of the appliances remaining connected to it. At the
time of removal of an existing appliance, the following steps must
be followed with each appliance remaining connected to the
common venting system placed in operation, while the other
appliances remaining connected to the common venting system
are not in operation.
1. Seal any unused openings in the common venting system.
2. Visually inspect the venting system for proper size and
horizontal pitch and determine that there is no blockage,
restriction, leakage, corrosion or other deficiency, which
could cause an unsafe condition.
3. Insofar as is practical, close all building doors and windows
and all doors between the space in which the appliances
remaining connected to the common venting system are
located and other spaces of the building. If applicable turn on
the clothes dryers and any appliances not connected to the
common venting system. Turn on any exhaust fans, such as
range hoods and bathroom exhausts, so they will operate at
maximum speed. Do not operate a summer exhaust fan.
Close fireplace dampers.
4. Place in operation the appliance being inspected. Follow the
lighting instructions. Adjust thermostat so that appliance
operates continuously.
5. If provided, test for spillage at the draft control device relief
opening after 5 minutes of main burner operation. Use a cold
mirror, or the flame of a match or candle.
6. After it has been determined that each appliance remaining
connected to the common venting system properly vents
when tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other gas-burning
appliance to their previous condition of use.
7. Any improper operation of the common venting system
should be corrected so that the installation conforms to the
National Fuel Gas Code, ANSI Z223.1/NFPA 54 and/or the
Natural Gas and Propane Installation Code, CSA B149.1-15
and CSA B149.2-15 Installation Codes. When resizing any
portion of the common venting system, the common venting
system should be resized to approach the minimum size as
determined using the appropriate tables in Chapter 13 of the
National Fuel Gas Code, ANSI Z223.1/NFPA 54 and /or the
Natural Gas and Propane Installation Code, CSA B149.1-15
and CSA B149.2-15 Installation Codes.
3.5 –Outdoor Venting
The VTech windproof cabinet protects the unit from weather,
meaning it is suitable for outdoor installation (By using special
kit).
1. Periodically check to ensure that air intake and vent cap are
not obstructed.
2. Locate appliance at least 3 feet away from any overhang.
3. Locate appliance at least ten feet from building air intake.
4. Avoid installation inareas where runoff from adjacent building
can spill onto appliance.
For outdoor installations, always consider the use of a shelter
such as a garden shed in lieu of direct exposure of the appliance
to the elements. The additional protection afforded by the shelter
will help to minimize nuisance problems with electrical
connections and will allow easier servicing of the appliance under
severe weather conditions.

16
Part 4 – Gas and Combustion
Hardware
Verify that the appliance is supplied with the type of gas specified
on the rating plate. Heating values of local natural gas are to be
between 950 and 1010 Btu/ft3. Consult factory if heating values
are outside this range or if a gas with a mixture of constituents is
being used. Consult factory for high altitude installations.
4.1 –Gas Piping and Connections
Safe operation of the VTech unit requires that the gas line size
chosen be sufficient to handle the total installed capacity, within
an acceptable range of pressure drop across the piping, and at
the available pressure. Gas pipe size may be larger than
appliance connection, if required for a specific pressure drop, but
it must not be smaller than the water heater connection. Table 3
can be used for gas line sizing data, please verify pipe size
requirements with gas supplier.
Table 3: Recommended Gas Pipe Size for Single Appliance
Input
KBtu/hr
Equivalent Length from NG Meter or LP Regulator
0-100 FT
101-200 FT
201-300 FT
NAT.
L.P.
NAT.
L.P.
NAT.
L.P.
80
¾”
½”
¾”
½”
1”
¾”
100
¾”
½”
1”
¾“
1”
¾”
125
1”
¾”
1 ¼”
1“
1 ¼”
1”
150
1”
¾”
1 ¼”
1“
1 ¼”
1”
199
1”
¾”
1 ¼”
1”
1 ¼”
1”
250
1 ¼”
1”
1 ¼”
1”
1 ½”
1 ¼”
299
1 ¼“
1“
1 ½”
1 ¼“
1 ½“
1 ¼“
399
1 ¼“
1“
1 ½“
1 ¼“
2“
1 ½“
499
1 ½“
1 ¼“
2“
1 ½“
2“
1 ½“
Installation of a union at the appliance gas line connection is
required for ease of service and removal of the gas train. Install
a manual main gas shutoff valve, outside of the appliance and
before the gas valve, as required by local codes.
Optional gas controls may require routing of bleeds and vents to
the atmosphere, outside the building when required by local
codes. Larger models of this appliance may be supplied with a
gas pressure relief valve. Thisvalve is designed to relieve lockup
pressure in excess of the high gas pressure switch setting. It
must be piped to discharge excess gas pressure through the
valve to a safe location in accordance with local codes.
All gas connections must be made with pipe joint compound
resistant to the action of liquefied petroleum and natural gas. All
piping must comply with local codes and ordinances. Use new,
properly threaded black iron pipe free from burrs. Avoid flexible
gas connections. Internal diameter of flexible gas lines may not
provide appliance with proper volume of gas. A trap (drip leg)
must be provided in the inlet gas connection to the appliance.
4.2 –Gas Supply Pressure
Gas supply pressure must be maintained within the specified
range in Table 4. Before operating the appliance, the complete
gas train and all connections must be purged of air and tested
using soap solution. The appliance and its individual gas shut-off
valve must be disconnected from the supply piping when
pressure testing the gas supply piping at pressures above ½ PSI.
Table 4: Gas Supply Pressure Range
Pressure Range
Propane
Natural Gas
Minimum (inches WC)
11
3*
Maximum (inches WC)
11
14
*7” WC recommended regulator setting
4.2.1 –Gas Regulators and Lockup Pressure
A stable gas supply pressure is important to achieve stable
operation on gas fired appliances using a 1:1 ratio control valve
for gas pressure regulation.
Lockup pressure (i.e. the pressure upstream of the gas valve
after closing) must not be in excess of 14” WC. It is paramount
that maximum lockup pressure be confirmed before any attempt
is made to start up the appliance. A suitable lockup regulator with
internal or external relief will not exceed running pressure by
more than 20%. An external relief valve may be required.
Operating the VTech at lockup pressures exceeding the
recommended levels can lead to delayed ignitions and damage
to the appliance.
NOTE: In facilities where the incoming gas pressure is
significantly higher than the pressure required by the water
heaters, it may be necessary for several regulators to work
together to stage the gas pressure down in a stable fashion.
Check with the gas supplier for more information.
The final stage gas regulator is to be located a minimum of 10
linear feet (do not factor in equivalent lengths for elbows) from
the appliance. Even regulators classified as fast reaction type
require appropriately dimensioned volumes of gas between the
regulator and appliance, to absorb the pressure swings caused
by fast flow rate variations, and avoid high lockup pressure.
4.3 –Air/Gas Ratio Control Valve
Operation of the gas valve in combination with the combustion
air fan allows the burner input rate to vary from 20% to 100%.
These utilize a 1:1 ratio dual seat negative pressure gas valve.
The gas valve adjusts fuel supply according to negative pressure
generated by the combustion fan. The valve is dual seat and
serves as a safety shut-off. The inlet gas supply pressure must
be maintained within the specified minimum and maximum
pressures (a reduction of up to 30% is permitted in the inlet gas
pressure between light-off and full fire conditions).
VT80 to 250 –1:1 Negative Pressure Control Valve
Gas Valve
Venturi
Low-fire adjustment screw (use Torx 40
for adjustment, clockwise increases CO2)
High-fire adjustment screw (use slotted
screwdriver for adjustment, counter-
clockwise increases CO2)

17
VT299 to VT399 –Negative Pressure Control Valve
VT499 –Negative Pressure Control Valve
4.4 –Gas Pressure Switches
Gas pressure switches prevent the burner from being activated
if pressure is outside certain ranges. Each switch is a physical
manual reset device, requiring physical depression of the reset
button if it is not closed prior to burner start or during burner
operation.
4.4.1 –Low Gas Pressure
A low gas pressure switch is standard equipment and monitors
the minimum incoming gas supply pressure supplied to the gas
train. If gas pressure upstream of the valve(s) falls below the
minimum setting of the pressure switch, the switch will open and
the appliance will shut down. An open gas pressure switch alarm
will be shown on the display.
4.4.2 –High Gas Pressure
High gas pressure switches maybe ordered to comply with CSD-
1 code. These will either be integrated in to the gas train. If gas
pressure downstream of the gas valve(s) exceeds the maximum
setting of the pressure switch, the switch will open and the
appliance will shut down.
Gas Pressure Switch (Cover Removed)
4.5 –Air Pressure Switches
4.5.1 –Blocked Flue Switch
All models use a normally closed blocked flue switch to shut
down the appliance under the following conditions:
Air intake 50% blocked
Vent outlet 80% blocked
4.5.2 –Low Air Switch
The low air switch is closed by operation of the combustion air
blower, to confirm that there is air flow present. This switch is
adjustable but typically does not need to be altered from factory
settings. Once this switch is closed the unit initiates the pre-purge
counter. If this switch opens during operation the unit will lock-
out.
4.6 –Combustion Air Blower
The VTech use a modulating air fan to provide combustible
air/gas mix to the burner and push the products of combustion
through the heat exchanger and venting system. The fan
assembly consists of a sealed housing and fan wheel
constructed from spark resistant cast aluminum. The fan is
operated by a fully enclosed 120 VAC, Single-Phase EC/DC
electric motor. The fan housing and motor assembly is fully
sealed and SHOULD NOT be field serviced. The power draw of
the motor is proportional to the modulated gas input rate of the
appliance.
VTech Combustion Air Fan
4.7 –Burner
This appliance uses a single cylindrical burner installed vertically
into the combustion chamber at the top of the heat exchanger.
The burner consists of a round mounting flange welded to a
mixing tube. The flange provides the transition from the
combustion air fan into the burner. The mixing tube is covered
with a knitted alloy material that forms the burner port surface.
The knitted burner port material is a metal fiber material which is
a unique alloy of iron, chrome, aluminum and several rare earth
metals. This alloy is designed to operate stress free as a burner
port surface. The burner port surface can sustain operation from
a blue flame down to infrared conditions as the burner input
varies.
VTech Burner
High-fire air gas ratio
adjustment (Use slotted
screwdriver for
adjustment, counter-
clockwise increases CO2)
Low-fire air gas ratio
adjustment (use Torx 40
for adjustment clockwise
increases CO2)
Low-fire air/gas ratio
adjustment, use slotted
screwdriver for adjustment,
clockwise increases CO2
Gas Inlet
Lift top cover to access
high fire air/gas ratio
adjustment (use 3mm
Allen key for adjustment,
counter-clockwise
increases CO2)