Hydro-Smart HS199CON-LP User manual

2Page
CONTENTS
Installaon Manual
SPECIFICATIONS.......................................................................................................................... 4
INTRODUCTION .......................................................................................................................... 5
SAFETY GUIDELINES.................................................................................................................... 6
INSTALLATION............................................................................................................................. 7
General.....................................................................................................................................7
Clearances................................................................................................................................9
Included accessories................................................................................................................9
Oponal items
........................................................................................................................ 10
High-altudeinstallaons
........................................................................................................ 11
Venng instrucons
...................................................................................................... 12
Gas supply and gas pipe sizing
............................................................................................................... 22
Water connecons
............................................................................................... 24
Condensate drain
................................................................................................................ 25
Electrical connecons
........................................................................................................ 27
Easy-Link System
......................................................................................... 28
Mul-Unit System
................................................................................................. 32
Hydro Smart Pre-built Panels
................................................................................................ 33
Hydro Smart Dual Purpose Panel..........................................................................................34
INITIAL OPERATION...................................................................................................................35
Owner's Guide
OPERATING SAFETY .................................................................................................................. 37
NORMAL OPERATION ............................................................................................................... 39
General...................................................................................................................................39
Temperaturesengs.............................................................................................................40
Temperature table of controller.............................................................................................40
Addionalfeatures.................................................................................................................41
Temperature sengs on the PCB (Without remote controller)............................................42
Flow.......................................................................................................................................43
Freeze protecon system.......................................................................................................43
Maintenance and service.......................................................................................................44
Unit draining .........................................................................................................................44
TROUBLESHOOTING...................................................................................................................45
General...................................................................................................................................45
Error codes............................................................................................................................ 47
COMPONENTSDIAGRAM...........................................................................................................50
PARTS LIST................................................................................................................................. 54
OUTPUT TEMPERATURE CHART................................................................................................ 56
LIMITED WARRANTY..................................................................................................................57
Contents

3 Page
Installaon Manual
CONGRATULATIONS
Congratulaons and thank you for choosing our condensing micro-
boiler. Before use, we recommend that you read through this safety
manual carefully. Please refer to the back of the manual for details about the
warranty.Keep this manual for future reference.
If you lose the manual, contact the manufacturer or your local
distributor.When you call, please tell us the model number and the
serial number of your unit wrien on the rang plate of the micro-
boiler.

4Page
SPECIFICATIONS
*40 psi or above is recommended for maximum flow.
** The Manifold Pressure is the factory seng and generally should not need adjustment.
NOTE:
•Check the rang plate to ensure this product matches your specificaons.
•In accordance with ANSI Z21.10.3, CO emission does not exceed 400 PPM for normal input.
• The manufacturer reserves the right to disconnue, or change at any me, specificaons or designs
without noce and without incurring obligaon.
Hydro Smart 199 Gas Condensing Micro-Boiler
Natural Gas Input
(Operang Range) BTU/h Min.: 15,000
Max.: 199,000
Propane Input
(Operang Range) BTU/h Min.: 13,000
Max.: 199,000
Gas Connecon 3/4" NPT
Water Connecons 3/4" NPT
Water Pressure* psi
(MPa) 15 - 150 (0.1 - 1)
Natural gas
Inlet Pressure
inch W.C.
(kPa)
Min. 5.0 (1.24)
Max. 10.5 (2.61)
Propane
Inlet Pressure
inch W.C.
(kPa)
Min. 8.0 (1.99)
Max. 14.0 (3.48)
Manifold
Pressure**
Natural
Gas
inch W.C.
(Pa)
2.95
(734)
Propane inch W.C.
(Pa)
3.3
(821)
Weight lbs. (kg) 59 (26.8)
Dimensions inch H 22.4 x W 17.7 x D 10.7
H 570 x W 450 x D 272
mm
Ignion Electric Ignion
Electric
Supply VAC / Hz 120 / 60
Consumpon
Operaon W / A 89.0 / 0.74
Standby W / A 4.2 / 0.04
Freeze-
Protecon W / A 175 / 1.5

5Page
INTRODUCTION
• This manual provides informaon necessary for the installaon, operaon, and maintenance
of the micro-boiler.
• The model descripon is listed on the rang plate which is aached to the side panel of the
micro-boiler.
• Please read all installaon instrucons completely before installing this product.
• If you have any problems or quesons regarding this equipment, consult the manufacturer or
its local representave.
• These high efficiency models have a built-in secondary heat exchanger that absorbs latent
heat from the exhaust gas.
• The principle behind condensing micro-boilers is simple:
*This diagram illustrates condensing micro-boiler design concepts only and does not accurately
represent the micro-boiler’s physical descripon.
1. Your thermostat indicates a need for heat and turns on a circulator pump.
2. Water enters the boiler.
3. The water flow sensor detects the water flow.
4. The computer iniates the fan motor and sends a signal to the igniter to create an ignion spark.
5. The gas ignites and flames appear within the burner chamber.
6. Water circulates through the heat exchanger and then gets hot.
7. Using thermistors to measure temperatures throughout the micro-boiler,the computer modulates
the gas and water valves to ensure proper output water temperature.
8. Your room reaches desired temperature and the micro-boiler shuts off.
Exhaust
Secondary
heat exchanger
Intake port
Condensate
drain port
Cold water inlet
Gas
Hot water outlet
Computer board Fan motor
Gas valves
Thermistor
Thermistor
Bypass valve
Primary
heat exchanger
Exhaust thermistor
Water control valve
Thermistor
Flow sensor
Burners

6 Page
SAFETY GUIDELINES
SAFETY DEFINITION
Indicates an imminently hazardous situaon which, if not avoided, will result in
death or serious injury.
DANGER
WARNING
Indicates an imminently hazardous situaon which, if not avoided, could result
in death or serious injury.
CAUTION
Indicates an imminently hazardous situaon which, if not avoided, could result
in minor or moderate injury.
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the most recent edion of the Naonal
Fuel Gas Code: ANSI Z223.1/NFPA 54 in the USA or CAN/CSA B149.1 Natural Gas, Propane Installaon
Code in Canada.
2. Properly ground the micro-boiler in accordance with all local codes or in the absence of local codes,
with the Naonal Electrical Codes: ANSI/NFPA 70 in the USA or CSA standard C22.1 Canada Electrical
Code Part 1 in Canada.
3. Carefully plan where you intend to install the micro-boiler. Please ensure:
• Your micro-boiler will have enough combusble air and proper venlaon.
• Locate your boiler where fluid leakage will not damage surrounding areas (please refer to p. 8).
4. Check the rang plate for the correct GAS TYPE, GAS PRESSURE, FLUID PRESSURE and ELECTRIC
RATING.
*If this micro-boiler does not match your requirements, do not install and consult with the manufac-
turer.
5. If any problem should occur, turn offall thermostats and turn offthe gas. Then call a trained
technician or the Gas Company or the manufacturer.
WARNING
• Do not store or use gasoline or other flammables, vapors, or liquids in the
vicinity of this appliance.
• Do not reverse the fluid and/or gas connecons as this will damage the gas
valves and can cause severe injury or death. Follow the diagram on p. 24
when installing your micro-boiler.
• Do not use this micro-boiler if any part has been in contact with or been
immersed in water. Immediately call a licensed plumber, a licensed gas fier,
or a professional service technician to inspect and/or service the micro-boiler
if necessary.
• Do not disconnect the electrical supply if the ambient temperature will drop
below freezing. The Freeze Protecon System only works if the micro-boiler
has electrical power. The heat exchanger will not be covered under warranty
if it is damaged due to freezing. Refer to the secon on the Freeze Protecon
System on p. 43 for more informaon.
Installaon Manual
Safety Guidelines

7Page
INSTALLATION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the most recent edion of the Naonal
Fuel Gas Code: ANSI Z223.1/NFPA 54 in the USA or CAN/CSA B149.1 Natural Gas, Propane Installaon
Code in Canada.
2. All gas micro-boiler require careful and correct installaon to ensure safe and efficient operaon.
This manual must be followed exactly. Read the “Safety Guidelines” Secon.
3. The manifold gas pressure is preset at the factory. It is computer controlled and should not need
adjustment.
4. Maintain proper space for servicing. Install the unit so that it can be connected or removed easily.
Refer to the "Clearances" Secon on p. 9 for proper clearances.
5. The micro-boiler must be installed in a locaon where the proper amount of combusble air will be
available to it at all mes without obstrucons.
6. The electrical connecon requires a means of disconnecon, to terminate power to the micro-boiler
for servicing and safety purposes.
7. Do not install the unit where the exhaust vent is poinng into any opening in a building or where the
noise may disturb your neighbors. Make sure the vent terminaon meets the required distance by
local code from any doorway or opening to prevent exhaust from entering a building. (Refer to p. 19.)
8. Parcles from flour, aerosols, and other contaminants may clog the air vent, build up and reduce
the funcons of the rotang fan, cause improper burning of the gas, or cause damage to the micro-
boiler. Regularly ensure that the area around the unit is dust- or debris-free. Regular maintenance is
recommended for these types of environment.
9. The Hydro Smart 199 Gas Condensing Micro-Boiler is to be installed indoors only. This unit is
equipped with a thermistor and hi-limit switch for the exhaust gas, detecng excess temperatures
within the flue and enabling the unit to safely stop operaons if needed. These components are
always monitoring exhaust gas condions in order to prevent heat damage to ABS, PVC, CPVC, or
polypropylene (Plasc) venng if ABS, PVC, CPVC, or polypropylene is used. If the exhaust gas
temperature exceeds 140 °F, these components will enable the unit to safely stop operaons.
• The micro-boiler requires a 3" or 4” make-up intake air supply pipe. The intake pipe must be
sealed airght.
• Air supply pipe can be made of ABS, PVC, CPVC, polypropylene, corrugated stainless steel, or
Category lll / IV stainless steel.
• Sidewall venng is recommended for this boiler. Vercal venng (roof terminaon) is acceptable.
•The manufacturer recommends running the exhaust vent and the intake pipe as parallel as possible.

8Page
INCLUDED ACCESSORIES
OPTIONAL ITEMS
• Installaon and service must be performed by a qualified installer (for
example, a licensed plumber or gas fier), otherwise the warranty will be
void.
• The installer (licensed professional) is responsible for the correct installaon
of the micro-boiler and for compliance with all naonal, state / provincial,
and local codes.
• The manufacturer does not recommend installing the micro-boiler in a pit or
locaon where gas and water can accumulate.
• Do not have the vent terminal poinng toward any operang window, door, or
opening into a building.
• Do not install next to any source of airborne debris, such as a clothes dryer,
that can cause debris to be trapped inside the combuson chamber, unless the
system is direct-vented.
• The manufacturer does not recommend installing the micro-boiler in an ac
due tosafety issues.If you install the micro-boiler in an ac:
• Make sure the unit will have enough combuson air and proper
venlaon.
• Keep the area around the micro-boiler clean. When dust collects on the
flame sensor, the micro-boiler will shut down on an error code.
• Place the unit for easy access for service and maintenance.
• A drain pan, or other means of protecon against water damage, is
required to be installed under the micro-boiler in case of leaks.
WARNING
• The warranty will not cover damage caused by water quality.
• Only dislled water or dislled water / glycol mixtures can be used with
this micro-boiler.Do not introduce pool or spa water, or any chemically
treated water into the micro-boiler.
• Water hardness levels must not exceed 7 grains per gallon (120 ppm) for
single family applicaons or more than 4 grains per gallon (70 ppm) for all
other types of applicaons. Water hardness leads to scale formaon and
may affect / damage the micro-boiler. Hard water scaling must be avoided
or controlled by proper water treatment.
• Water pH levels must be between 6.5 and 8.5
• Well water must be treated.
• Do not install the unit where water, debris, or flammable vapors may get into
the flue terminal.
• Although the micro-boiler is designed to operate with minimal sound, the
manufacturer does not recommend installing the unit on a wall adjacent toa
bedroom, or a room that is intended for quiet study or meditaon, etc.
• Locate your boiler close to a drain where water leakage will not do damage
to surrounding areas. As with any water heang appliance, the potenal for
leakage at some me in the life of the product does exist. The manufacturer
will not be responsible for any water damage that may occur. If you install a
drain pan under the unit, ensure that it will not restrict the combuson air flow.
CAUTION

9Page
Maintain all clearances around
the micro-boiler.
CLEARANCES
INCLUDED ACCESSORIES
Model Top Boom Front Back Sides
HS199Con-NG
(Natural Gas)
36 in.
(914 mm)
12 in.
(305 mm)
24 in.
(610 mm)
0.5 in.
(13 mm)
2 in.
(51 mm)
*24 inches recommended for maintenance.
Back
Side
Front
Side
Top
Check that these items below are included with the micro-boiler.
Installaon manual and owner’s
guide
Bird screen Communicaon cable
Qty: 1 Qty: 1
Qty: 2
HS199Con-LP
(Liquid propane)
36 in.
(914 mm)
12 in.
(305 mm)
24 in.
(610 mm)
0.5 in.
(13 mm)
2 in.
(51 mm)

11 Page
HIGH-ALTITUDE INSTALLATIONS
Check the elevaon where your micro-boiler is installed. Set DIPswitches shown in the table below
depending on the altude.
WARNING
DO NOT adjust any DIPswitches on the upper bank.
NOTE: The dark squares indicate the direcon the DIPswitches should be set to.
Computer board
Lower bank of DIPswitches
0 (DEFAULT) Up to 2,500 Up to 5,000 Up to 7,500 Up to 10,100 
HS199Con Boiler
(Lower bank of
DIPswitches) No. 2 : OFF
No. 3 : OFF
No. 4 : OFF
No. 2 : OFF
No. 3 : ON
No. 4 : OFF
No. 2 : OFF
No. 3 : OFF
No. 4 : ON
No. 2 : OFF
No. 3 : ON
No. 4 : ON
No. 2 : ON
No. 3 : ON
No. 4 : ON
OFF
ON
1 2 3 4 5 6
OFF
ON
1 2 3 4 5 6
OFF
ON
1 2 3 4 5 6
OFF
ON
1 2 3 4 5 6
Altude
DIPswitches
OFF
ON
1 2 3 4 5 6

12 Page
VENTING INSTRUCTIONS
-General-
This appliance must be vented in accordance with the secon “Venng of Equipment" of the latest
edion of the Naonal Fuel Gas Code: ANSI Z223.1/NFPA 54 in the United States and/or Secon 7 of the
CAN/CSA B149.1 Natural Gas and Propane Installaon Code in Canada, as well as applicable local building
codes.
The use of venng materials approved for Category III/IV appliances is recommended whenever possible.
However, this appliance may also be vented with plasc pipe materials such as ABS, PVC, CPVC, or
polypropylene. For details, please refer to the Exhaust Vent (ABS, PVC, CPVC, or polypropylene Vent)
Secon from p. 15. Vent installaons in Canada which ulize plasc vent systems must use venng that
complies with ULC S636.
General rules for venng micro-boilers are:
• Place the micro-boiler as close as possible to the vent terminaon.
• The vent collar of the micro-boiler must be fastened directly to an unobstructed vent pipe.
• Do not weld the vent pipe to the micro-boiler’s vent collar.
• Do not cut the vent collar of the unit.
• The vent must be easily removable from the top of the micro-boiler for normal service and
inspecon of the unit.
• The micro-boiler vent must not be connected to any other gas appliance or vent stack.
• Avoid using an oversized vent pipe or using extremely long runs of the pipe.
• For rooop venng, a rain cap or other form of terminaon that prevents rain water from
entering into the micro-boiler must be installed.
• Do not terminate vent into a chimney. If the vent must go through the chimney, the vent must
run all the way through the chimney with approved vent pipe.
General rules for vent terminaons:
• Avoid locang the micro-boiler vent terminaon near any air intake devices. These fans can
pick up the exhaust flue products from the micro-boiler and return them to the building. This
can create a health hazard.
• Locate the vent terminaon so that it cannot be blocked by any debris, at any me. Most codes
require that the terminaon be at least 12 in. (305 mm) above grade, but the installer may
determine if it should be higher depending on the job site condion and applicable codes.
• A proper sidewall terminaon is recommended when the micro-boiler is vented through a
sidewall.
• Regarding the clearances from the exhaust terminaon to the air inlet or opening, refer to p.
19-21.
• Improper venng of this appliance can result in excessive levels of carbon
monoxide which can result in severe personal injury or death.
• Improper installaon can cause nausea or asphyxiaon, severe injury or death
from carbon monoxide and flue gases poisoning. Improper installaon will
void product warranty.
DANGER
When installing the vent system, all applicable naonal and local codes must be
followed. If you install thimbles, fire stops or other protecve devices and they
penetrate any combusble or noncombusble construcon, be sure to follow all
applicable naonal and local codes.
CAUTION

13 Page
-DIPswitch sengs for Vent length-
4" venng
Vent length (Upper bank of DIPswitches)
5 to 50 
(DEFAULT) No. 3 : ON
No. 4 : OFF
51 to 100 
No. 3 : OFF
No. 4 : OFF
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8
3" venng
Vent length (Upper bank of DIPswitches)
5 to 20 
(DEFAULT) No. 3 : ON
No. 4 : OFF
21 to 40 
No. 3 : OFF
No. 4 : OFF
41 to 70 
No. 3 : ON
No. 4 : ON
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8
Set DIPswitches shown in the tables below depending on the vent length.
3" venng
Vent length (Upper bank of DIPswitches)
5 to 45 
(DEFAULT) No. 3 : ON
No. 4 : OFF
46 to 70 
No. 3 : OFF
No. 4 : OFF
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8
Set DIPswitches shown in the table below depending on the vent length.
<Single pipe with room-air intake
<Two-pipe, direct-vent
Refer to p. 15 for details.
Refer to p. 16 for details.

14 Page
-Exhaust vent (ABS, PVC, CPVC, or polypropylene vent)-
This appliance can be vented with ABS, PVC, CPVC, or polypropylene (temperature rated up to at
least 149 °F). Vent material cerfied to ULC S636 standards is recommended in the USA. In Canada,
plasc venng must be cerfied to ULC S636 standards.
• The maximum length of exhaust vent piping must not exceed 70 . (21.3 m) for 3” venng, which
depends on the elevaon where the micro-boiler is installed, and 100 . (30.5 m) for 4” venng
(deducng 5 . (1.5 m) for each elbow used in the venng system). Do not use more than 5
elbows. See the table below.
• When the horizontal vent run exceeds 5 . (1.5 m), support the vent run at 3 . (0.9 m) intervals
with overhead hangers.
Item Material United States Canada
Exhaust pipe and
Fings
Schedule 40 PVC ANSI/ASTM D1785
ULC S636 Cerfied
Materials Only
PVC-DWV ANSI/ASTM D2665
Schedule 40 CPVC ANSI/ASTM F441
Schedule 40 ABS-DWV ANSI/ASTM D2661
Polypropylene UL-1738
Pipe Cement/Primer
PVC ANSI/ASTM D2564
CPVC ANSI/ASTM F493
ABS ANSI/ASTM D2235
NOTE: Do NOT Use Cellular Foam Core Pipe
Diameter Max. No. of Elbows Max. Vercal and Horizontal (Total) Vent Length
3 in. (76 mm) 5 70 . (21.3 m)
4 in. (102 mm) 5 100 . (30.5 m)
*For each elbow added, deduct 5 . (1.5 m) from max. vent length.
No. of Elbows
Max. Vercal or Horizontal (Total) Vent Length
3" venng 4" venng
Up to 3,000 Up to 6,000 Up to 10,100 Up to 10,100 
0 70 . (21.3 m) 40 . (12.2 m) 25 . (7.6 m) 100 . (30.5 m)
1 65 . (19.8 m) 35 . (10.7 m) 20 . (6.1 m) 95 . (29.0 m)
2 60 . (18.3 m) 30 . (19.1 m) 15 . (4.6 m) 90 . (27.4 m)
5 45 . (13.7 m) N/A N/A 75 . (22.9 m)
Excludes vent terminators, terminaon elbows, or rain caps.
For details on the vent connecon, refer to p. 15 and p. 16.

15 Page
For details of the oponal items, refer to the Installaon manual for each oponal item.
<How to install intake and exhaust venng (two-pipe, direct-vent)
3" vent
From 3" to 4" vent
3” coupling
Exhaust vent collar
(Female)
3” straight pipe
3” coupling
Intake vent collar
(Female)
3” straight pipe
1. Connect 3" couplings directly on the
exhaust and intake vent collar
of the micro-boiler.
2. Connect 3” straight pipes to the
couplings.
1. Connect 3"x4" increasers
directly on the exhaust and intake
vent collar of the micro-boiler.
2. Connect 4” straight pipes to
the increasers.
4” straight pipe
3"x4" increaser
Exhaust vent collar
(Female)
Intake vent collar
(Female)
4” straight pipe
3"x4" increaser
Horizontal
Roof
Roof
Fire stop
Wall
Connect between exhaust vent collar and piping.
See the below.
Typical using PVC, ABS, or polypropylene vent

16 Page
For details of the oponal items, refer to the Installaon manual for each Oponal item.
<How to install single vent>
3" vent
From 3" to 4" vent
1. Connect a 3" elbow directly
on the intake vent collar of the
micro-boiler.
2. Connect a 3" coupling directly
on the exhaust vent collar of the
micro-boiler.
3. Connect a 3” straight pipe to
the coupling.
Typical using PVC, ABS, or polypropylene vent
1. Connect a 3" elbow directly
on the intake vent collar of the
micro-boiler.
2. Connect a 3"x4" increaser directly
on the exhaust vent collar of the
micro-boiler.
3. Connect a 4” straight pipe to the
increaser.
3” coupling
3” straight pipe
Exhaust vent collar
(Female)
3” elbow with
bird screen
Intake vent collar
(Female)
4” straight pipe
3"x4" increaser
Exhaust vent collar
(Female)
3” elbow with
bird screen
Intake vent collar
(Female)
Horizontal
Roof
Fire stop
Connect between exhaust vent collar and piping.
See the below.
Roof
Elbow
Elbow
Wall

17 Page
-Exhaust vent (Stainless steel vent)-
This is a Category IV appliance and must be vented accordingly. The vent system must be sealed airght.
All seams and joints without gaskets must be sealed with high heat resistant silicone sealant or UL listed
aluminum adhesive tape having a minimum temperature rang of 160 °F. For best results, a vent system
should be as short and straight as possible.
• The micro-boiler is a Category IV appliance and must be vented accordingly with any 4” vent
approved for use with Category III/IV or Special BH type gas vent.
• The manufacturer recommends the NovaVent line.However, the following are also UL listed
manufacturers: ProTech Systems Inc. (FasNSeal), Metal-Fab Inc., and Heat-Fab Inc. (Saf-T Vent).
• Follow the vent pipe manufacturer’s instrucons when installing the vent pipe.
• The maximum length of exhaust vent piping must not exceed 100 . (30.5 m) (deducng 5. (1.5
m) for each elbow used in the venng system). Do not use more than 5elbows.
• When the horizontal vent run exceeds 5. (1.5 m), support the vent run at 3 . (0.9 m) intervals
with overhead hangers.
Diameter Max. No. of Elbows Max. Vercal and Horizontal (Total) Vent Length
4 in. (102 mm) 5 100 . (30.5 m )
*For each elbow added, deduct 5 . (1.5 m) from max. vent length.
No. of Elbows Max. Vercal or Horizontal Vent Length
0 100 . (30.5 m)
195 . (29.0 m)
2 90 . (27.4 m)
5 75 . (22.9 m)
Excludes vent terminators, terminaon elbows, or rain caps.

19 Page
Canada U.S.A
Direct-vent and other
than Direct-vent
Direct-
vent
Other than
Direct-vent
AClearance above grade, veranda, porch, deck, or
balcony 1 foot 1 foot 1 foot
B Clearance to window or door that may be opened 3 feet 1 foot
4 feet from below or
side opening. 1 foot
from above opening
C Clearance to permanently closed window * * *
D
Vercal clearance to venlated soffit located above
the vent terminator within a horizontal distance
of 2 feet (61cm) from the center line of the
terminator
* * *
E Clearance to unvenlated soffit * * *
F Clearance to outside corner * * *
G Clearance to inside corner * * *
HClearance to each side of center line extended
above meter/regulator assembly 3 feet * *
I Clearance to service regulator vent outlet 3 feet * *
J
Clearance to non-mechanical air supply inlet to
building or the combuson air inlet to any other
applicaon
3 feet 1 foot
4 feet from below or
side opening. 1 foot
from above opening
K Clearance to mechanical air supply inlet 6 feet 3 feet 3 feet
LClearance above paved sidewalk or paved driveway
located on public property 7 feet * 7 feet
M Clearance under veranda, porch deck, or balcony 1 foot * *
*For clearances not specified in ANSI Z223.1 / NFPA 54 or CAN/CSA-B149.1, please use clearances in accordance
with local installaon codes and the requirements of the gas supplier.
INSIDE CORNER DETAIL
V
Gas meter / regulator
V
V
V
V
V
V
V
V
V
X
X
X
Vent terminal
Air supply inlet
Area where is not permied
G
A
E
D
B
L
C
F
B
B
B
BA
J
OPERABLE FIXED
CLOSED
B
H
M
K
OPERABLE
FIXED
CLOSED
I

20 Page
For mulple sidewall exhaust terminaons (e.g. Mul-
Unit Systems), an exhaust terminaon must be at least 1
. (305mm) away from another exhaust terminaon. An
exhaust terminaon must also be at least 2 . (610 mm)
away from an inside corner. (If the adjacent wall is less than
2 . (610 mm) of length, the minimum required distance
away from the inside corner will be equal to the length of
that adjacent wall.)
For mulple-unit, direct-vent sidewall terminaons that
combine the intake and exhaust into a single penetraon,
space each direct-vent terminaon at least 1 . (305 mm)
away from each other, no maer the orientaon. A direct-
vent terminaon must also be at least 2 . (610 mm) away
from an inside corner. (If the adjacent wall is less than 2 .
(610 mm) of length, the minimum required distance away
from the inside corner will be equal to the length of that
adjacent wall.)
Exhaust
terminaon
Inside
corner
1 .
(305 mm) min
2 .
(610 mm) min
1 . (305 mm)
min
Combined
intake and
exhaust
terminaon
Inside
corner
1 .
(305 mm) min
2 .
(610 mm)min
1 . (305 mm)
min
For direct-vent sidewall
terminaons that use two
separate penetraons for
the intake and exhaust,
keepthe terminaon
clearances shown in the
diagrams on the right.
Please follow all local and naonal codes in regards to proper terminaon
clearances. In the absence of such codes, the clearances below can be used as
guidelines. Local codes supersede these guidelines.
CAUTION
1 . (305 mm) min
0.5 
(159 mm) min
Exhaust
Intake
Exhaust
Intake
<Case 2>
1 . (305 mm)
min
0.5 .
(159 mm) min
0.5 .
(159 mm)
min
Exhaust
Intake
Exhaust
Intake
<Case 1>