Raypak RAYTHERM 0042B Manual

INSTALLATI N & PERATING
INSTRUCTI NS
CATALO NO. 2100.50AB Effective: 09-02-09 Replaces: 12-26-07 P/N 240488 Rev. 29
WARNING: If these instructions are not followed exactly, a fire or explosion may
result causing property damage, personal injury or death.
F R Y UR SAFETY: Do not store or use gasoline or other flammable vapors and
liquids or other combustible materials in the vicinity of this or any other appliance. To
do so may result in an explosion or fire.
WHAT T D IF Y U 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 neighbor's phone. Follow the gas
supplier's instructions.
• If you cannot reach your gas supplier, call the fire department.
Installation and service must be performed by a qualified installer, service agency or
the gas supplier.
This manual should be maintained in legible condition and kept adjacent to the heater or in another safe place for
future reference.
Models 0042B, 0066B, 0090B
0135B & 0180B – Type H
Raytherm™
Residential
Boilers

2
Rev. 29 reflects the following:
Changes to: Note on Page 8, text on Page 10, Item 7 on Page 11, mounting instructions on Page 12

WARNINGS 4
Pay Attention to These Terms 4
RECEIVING EQUIPMENT 5
GENERAL SPECIFICATI NS 5
INSTALLATI N 7
Code Requirements 7
Mounting Base 7
Clearance Requirements 7
Combustion/Ventilation Air 8
Venting Connections 9
Vent Damper Installation Location 11
VENT DAMPER WIRING
DIAGRAM 14
as Supply Connections 15
as Pressure 15
Water Connections & System Piping 15
Electrical Wiring 18
WIRING DIAGRAMS 19
SERVICING PR CEDURES 26
eneral Location of Controls 26
SEQUENCE F PERATI N 26
Intermittent Ignition Device (IID) 26
START-UP PR CEDURES 27
Lighting the Boiler 27
For Standing Pilot Models 27
Filling the System 27
Checking the Circulator 27
For Standing Pilot Models with
Robertshaw as Valve, 2-stage
Operation (Models 90, 13 & 180) 28
To Turn Off as to the Boiler
(Models 90, 135 & 180) 28
For Automatic Ignition Models 28
For Intermittent Ignition (IID)
with Honeywell or Robertshaw
as Valve (All Models) 29
To Turn Off as to the Boiler 29
Shut-down Procedure 29
Testing the Ignition afety Shut-off 30
Safe Shut-down Tests 30
Inspection Procedures 31
REPAIR PR CEDURES 32
Tube Cleaning Procedure 32
Heat Exchanger Removal 32
Heat Exchanger Re-assembly 33
Combustion Chamber Removal 33
TR UBLESH TING 34
Adjustment & Replacement of
Components 36
Replacement Parts 37
WARRANTY 38
C NTENTS
3

DANGER: Indicates the presence of immediate hazards which will cause severe
personal injury, death or substantial property damage if ignored.
WARNING: Indicates the presence of hazards or unsafe practices which could cause
severe personal injury, death or substantial property damage if ignored.
CAUTI N: Indicates the presence of hazards or unsafe practices which could cause
minor personal injury or product or property damage if ignored.
N TE: Indicates special instructions on installation, operation, or maintenance which
are important but not related to personal injury hazards.
WARNING—CALIF RNIA PR P SITI N
65: This product contains chemicals known to the
State of California to cause cancer, birth defects or
other reproductive harm.
WARNINGS
Pay Attention to These Terms
4
N TE: These instructions are provided to ensure
the proper installation and operation of Raypak
boilers. Should questions arise regarding the
specifications, installation, operation or servicing of
these boilers, we suggest that the local Sales
representative or the factory be consulted.
WARNING: This unit contains refractory ceramic
fiber (RCF) insulation in the combustion chamber.
RCF, as manufactured, does not contain respirable
crystalline silica. However, following sustained
exposure to very high temperatures (>2192F), the
RCF can transform into crystalline silica
(cristabolite). The International Agency for Research
on Cancer (IARC) has classified the inhalation of
crystalline silica (cristabolite) as carcinogenic to
humans.
When removing the burners or heat exchangers,
take precautions to avoid creating airborne dust and
avoid inhaling airborne fibers. When cleaning spills,
use wet sweeping or High Efficiency Particulate Air
(HEPA) filtered vacuum to minimize airborne dust.
Use feasible engineering controls such as local
exhaust ventilation or dust collecting systems to
minimize airborne dust. Wear appropriate personal
protective equipment including gloves, safety
glasses with side shields, and appropriate NIOSH
certified respiratory protection, to avoid inhalation of
airborne dust and airborne fiber particles.
WARNING: To minimize the possibility of improper
operation, serious personal injury, fire, or damage to
the heater:
• Always keep the area around the heater free of
combustible materials, gasoline, and other flam-
mable liquids and vapors.
• Heater should never be covered or have any
blockage to the flow of fresh air to the heater.
WARNING: Do not use this heater if any part has
been under water. Immediately call a qualified
service technician to inspect the heater and to
replace any part of the control system and any gas
control which has been under water.
WARNING: Should overheating occur or the gas
supply valve fail to shut, do not turn off or disconnect
the electrical supply to the heater. Instead, shut off
the gas supply at a location external to the heater.
DANGER: Make sure the gas on which the heater
will operate is the same type as that specified on the
heater rating plate.

RECEIVING EQUIPMENT
On receipt of your equipment, visually check for exter-
nal damage to the carton. If the carton is damaged, it
is suggested that a note be made on the Bill of Lading
when signing for the equipment.
Remove the boiler from the carton, and if it is dam-
aged, report the damage to the carrier immediately. Be
sure that you receive the number of packages indicat-
ed on the Bill of Lading. Claims for shortages and
damages must be filed with carrier by consignee.
Purchased parts are subject to replacement only
under the manufacturer's warranty. Debits for defec-
tive replacement parts will not be accepted and
defective parts will be replaced in kind only per our
standard warranties.
When ordering parts, you must specify Model and
Serial Number of the boiler. When ordering under war-
ranty conditions, you must also specify date of
installation.
Raypak recommends that this manual be reviewed
thoroughly before installing the boiler. If there are
any questions which this manual does not answer,
please contact your local Raypak representative.
GENERAL
SPECIFICATI NS
Raytherm hydronic boilers are design certified and
tested under the requirements of the latest edition of
the American National Standard, ANSI Z21.13/CSA
4.9. Each boiler has been constructed and pressure
tested in accordance with the requirements of Section
IV of the American Society of Mechanical Engineers
Code, and factory fire tested.
These boilers are designed for indoor installation with
a built-in drafthood, and a built-in sub-base for com-
bustible flooring. Models are available with standing
pilot, or with an intermittent ignition device (IID).
These boilers are equipped with the following compo-
nents: water circulation pump, pressure relief valve,
temperature/pressure gauge, adjustable high limit
switch, drain valve, fast response temperature sensor,
40 VA transformer, pump relay, vent thermal switch,
flame roll-out switch, and redundant combination gas
valve. Two-stage gas valve (50% firing on first stage)
is standard on models H-0090, H-0135 and H-0180.
The automatic ignition models and some standing pilot
models are provided with a plug-in connector that is
compatible with the Honeywell D80D vent damper.
Similar type vent dampers made by other manufactur-
ers, and design certified by a nationally-recognized
testing agency, under the ANSI Z21.66 standard, may
also be used.
Follow the installation instructions furnished with the
vent damper package. The plug-in connector can also
be used with power venters. Refer to the specific
installation instructions supplied by the power vent
manufacturer.
5

6
16
331/4
221/8
12
1
/2
5
18
31
/4
2
THERMOSTAT CONN
(ELECTRICAL CONN
ON OTHER SIDE) GAS
CONN
3/4 NPT PIPE
TO DRAIN
261/
41
/2
C
117
/8
6
INLET
OUTLET
31
/8
MIN
19
K
AUTOMATIC
VENT DAMPER
(FIELD INSTALLED)
B
A
Fig. 1: Dimensions
Model
No.
Input
MBH
Heating
Capacity
MBH
Net
I=B=R
Rating
Piping Connections
A B C
K
Vent
Dia.
Water
NPT Gas NPT
H-0042 4235301in. 1/2 in. 11 in. 53/4 in. 51/2 in. 4in.
H-0066 66 54 47 1 in. 1/2 in. 11 in. 5 3/4 in. 5 3/4 in. 5 in.
H-0090 90 74 64 1 in. 1/2 in. 11 in. 5 3/4 in. 5 3/4 in. 5 in.
H-0135 135 109 95 1 1/4 in. 1/2 in. 18 in. 6 1/4 in. 6 1/4 in. 6 in.
H-0180 180 148 129 1 1/4 in. 1/2 in. 18 in. 6 1/4 in. 8 in. 7 in.
Table A: Specifications

7
INSTALLATI N
Code Requirements
Installation must be in accordance with local codes, or
in the absence of local codes, with the latest editions
of the National Fuel as Code, ANSI Z223.1, and the
National Electrical Code, ANSI/NFPA 70. In Canada,
installations must conform with the current CSA B149
and the Canadian Electrical Code Part 1 CSA C22.2
No.1. Where required by the authority having jurisdic-
tion, the installation must conform to American Society
of Mechanical Engineers Safety Code for Controls and
Safety Devices for Automatically Fired Boilers, CSD-1.
Mounting Base
Boiler should be mounted on a level surface. Each
boiler is designed with a built-in sub-base approved for
mounting the boiler on combustible flooring. Boiler
must NOT be installed on carpet.
In addition, the boiler shall be installed such that the
gas ignition system components are protected from
water (dripping, spraying, rain, etc.) during appliance
operation and service (circulator replacement, control
replacement, etc.) Clearance Requirements
1. Minimum clearances from combustible materials
are listed in Table B below.
2. A front clearance of at least 24" is recommended
for adequate service of burner-tray and controls.
N TE: This boiler should be located in an area
where water leakage will not result in damage to the
area adjacent to the appliance or to the structure.
When such locations cannot be avoided, it is
recommended that a suitable drain pan, adequately
drained, be installed under the appliance. The pan
must not restrict air flow.
Model
No. Floor Front Back Right Left Top Flue
Vent
0042
0066 Comb. 4 in. 6 in. 6 in. 6 in. 16 in. 6 in.
0090
0135
0180
Comb. Alcove 6 in. 6 in. 6 in. 16 in. 6 in.
Fig. 2: Mounting Base
Table B: Minimum Clearances From Combustible Materials

8
3. Except for carpeted flooring, boilers are certified
for installation on combustible floors.
4. For un-insulated hot water pipes, maintain a 2"
clearance, or consult local authority having juris-
diction.
Combustion/Ventilation Air
1. The boiler must be provided with adequate supply
of air for proper combustion and ventilation in
accordance with the latest edition of the National
Fuel as Code, ANSI Z223.1, or applicable provi-
sions of the local building codes.
2. Models 0042 and 0066 only: When the boiler is
installed in a confined space such as a utility room
or closet where all air is supplied from inside the
building, the boiler room must be provided with
two openings, each one having a minimum net
free area, in square inches as shown in Table C.
WARNING: Air supply to the boiler room must not
be affected by mechanical exhaust vents located in
other parts of the house, such as kitchen or
bathroom fans, or attic blowers. Mechanical exhaust
vents may create a negative pressure condition in
the boiler room that can become a hazard of
asphyxiation, explosion or fire.
CAUTI N: Combustion air must not be
contaminated by corrosive chemical fumes which
can damage the boiler. Measures must be taken to
prevent the entry of corrosive chemical fumes to the
combustion and ventilation air supply. Such
chemicals include, but are not limited to, chlorinated
and/or fluorinated hydrocarbons such as found in
refrigerants, aerosol propellants, drycleaning fluids,
degreasers, and paint removers. Other harmful
elements may come from bleaches, air fresheners,
or mastics. Vapors from these types of products can
form corrosive acid compounds when burned in a
gas flame. The resulting acid condensate can
damage or substantially reduce the life of the heater.
It may be necessary to provide outside air directly to
the heater in order to avoid this problem.
One opening shall be within 12" of the top, and the
other opening within 12" of the floor. If additional gas
appliances are installed in the same space, the total
input of all gas appliances installed in the same space,
must be considered in the calculation. Refer to the lat-
est edition of the National Fuel as Code for additional
requirements.
3. If the boiler room is located against an outside wall
and air openings can communicate directly with the
outdoors, the two openings on the outside wall must
each have a net free area as shown in Table D.
Model No. Sq. in. of Free Area
0042
0066 70
Table C: Minimum Net Free Area
N TE: If louvers, grills or screens are used on the
openings, obtain the net free area requirements from
their supplier or manufacturer. If the design free area
of a louver is not known nor available, it shall be
assumed that wood louvers will have 20-25 percent
free area and metal louvers will have 60-75 percent
free area as specified in the National Fuel as Code.
Model No. Sq. in. of Free Area
0042 12
0066 18
0090 24
0135 35
0180 45
Table D: Minimum Net Free Area
Fig. 3: Location of Openings for
Combustion/Ventilation Air

9
Location of the openings is the same as in the previ-
ous case - that is, within 12" of the top, and within 12"
of the bottom of the enclosure. If horizontal ducts are
used, the area must be doubled and the duct area
shall not be less than the area of the openings they
connect, and in no case shall the smallest dimension
be less than 3".
Venting Connections
These boilers have built-in drafthoods. Vent piping the
same size or larger than the drafthood outlet is recom-
mended; however, when the total vent height
(drafthood outlet to vent terminal) is at least ten (10)
feet, the vent pipe size may be reduced by one size
only as specified in the latest edition of the National
Fuel as Code, ANSI Z223.1.
As much as possible, avoid long horizontal runs of
vent pipe and too many elbows. If installation requires
horizontal runs, the vent pipe must have a minimum of
1/4 inch per foot rise and should be supported at not
less than five foot intervals. Maximum vent connector
horizontal length shall be 1-1/2 feet (18 inches) for
each inch of connector diameter as shown in Table E.
as vents supported only by the flashing and extend-
ing above the roof more than five feet should be
securely guyed or braced to withstand snow and wind
loads. We recommend use of insulated vent pipe
spacer through the roofs and walls.
For protection against rain or blockage by snow, the
vent pipe must terminate with a listed vent cap which
complies with the local codes or, in the absence of
such codes, to the latest edition of the National Fuel
as Code, ANSI Z223.1.
The discharge opening must be a minimum of two (2)
feet vertically from the roof surface and at least two (2)
feet higher than any part of the building within ten (10)
feet. Vent stack shall be at least five (5) feet in vertical
height above the drafthood outlet.
The vent cap location shall have a minimum clearance
of four (4) feet horizontally from, and in no case above
or below, unless a 4-foot horizontal distance is main-
tained, from electric meters, gas meters, regulators
and relief equipment.
The weight of the vent stack or chimney must not rest
on the boiler's drafthood. Support must be provided in
compliance with applicable codes. The boiler top and
drafthood must be readily removable for maintenance
and inspection. Vent pipe should be adequately sup-
ported to maintain proper clearances from combustible
construction.
Type "B" double-wall (or equivalent) vent pipe is rec-
ommended. However, single-wall metal vent pipe may
be used as specified in the latest edition of the
National Flue as Code ANSI Z223.1.
Model No.
Vent
Connector
Diameter (in.)
Max.
Horizontal
Length (ft)
0042 4 6
0066, 0090 5 7.5
0135 6 9
0180 7 10.5
Table E: Maximum Horizontal Length of Vent Pipe
Lowest Discharge
Opening
Listed Cap
Listed Gas Vent
X
12
Roof Pitch is X/12
H - Minimum Height from
Roof to Lowest
Discharge Opening
Fig. 4: Minimum Height from Roof to Lowest Discharge
Opening
Refer to Table F for detailed information

10
Roof Pitch (X/12) H (Min. ft)
Flat to 6/12 1
6/12 to 7/12 1.25
Over 7/12 to 8/12 1.5
Over 8/12 to 9/12 2
Over 9/12 to 10/12 2.5
Over 10/12 to 11/12 3.25
Over 11/12 to 12/12 4
Over 12/12 to 14/12 5
Over 14/12 to 16/12 6
Over 16/12 to 18/12 7
Over 18/12 to 20/12 7.5
Over 20/12 to 21/12 8
Table F: Minimum Height from Roof to Lowest
Discharge Opening
Refer to Fig. 4 for graphical reference
For connections to gas vents or chimneys, vent instal-
lations shall be in accordance with the Venting of
Equipment section of the National Fuel as Code,
ANSI Z223.1, or applicable provisions of the local
building codes.
Common Vents
Manifolds that connect more than one boiler to a com-
mon chimney must be sized to handle the combined
load. Consult available guides for proper sizing of the
manifold and the chimney. At no time should the area
be less than the area of the largest outlet.
Fig. 5: Minimum Venting Measurements
WARNING: These boilers must not be connected
into any portion of mechanical draft systems
operating under positive pressure. To do so may
cause the flue products to be discharged into the
living space causing serious health injury.
Fig. 6: Common Venting

11
At the time of removal of an existing boiler, the follow-
ing steps shall be followed with each appliance
remaining connected to the common venting system
placed in operation, while the other appliances remain-
ing 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 make sure there is no
blockage or restriction, leakage, corrosion and
other deficiencies 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 com-
mon venting system are located and other spaces
of the building. Turn on clothes dryers and any
appliance not connected to the common venting
system. Turn on any exhaust fans, such as range
hoods and bathroom exhausts, so they will oper-
ate 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 appliance will operate continuously.
5. Test for spillage at the drafthood relief opening
after 5 minutes of main burner operation. Use the
flame of a match or candle, or smoke from a ciga-
rette, cigar or pipe to visually check spillage.
6. After it has been determined that each appliance
remaining connected to the common venting sys-
tem properly vents when tested as outlined above,
return doors, windows, exhaust fans, fireplace
dampers and any other gas burning appliance to
their previous conditions of use.
7. Any improper operation of the common venting
system should be corrected so that the installation
conforms with the latest edition of the National
Fuel as Code, ANSI Z223.1. When resizing any
portion of the common venting system, the com-
mon venting system should be resized to
approach the minimum size as determined using
the appropriate tables in the National Fuel as
Code, ANSI Z 223.1 and CSA - B149.
Vent Damper Installation
Location
The vent damper supplied with each boiler must be
located in the vent so that it serves only the appliance
for which it is intended.
If improperly installed, a hazardous condition, such as
an explosion or carbon monoxide poisoning, could
result. Make certain that it is mounted in an accessible
location at least 6 in. (152.4 mm) from any combustible
material or the heat exchanger and that the position
indicator is in a visible location.
The vent damper must be installed at the appliance
drafthood, and without modification of the drafthood.
To connect the vent damper wiring to the boiler wiring,
connect the damper circuit plug to the boiler circuit
plug.
Fig. 7: Vent Damper Location
WARNING: Carefully read and follow the
installation instructions furnished with the vent
damper package. Failure to follow these instructions
can cause asphyxiation, explosion or fire.

12
Mounting
On vertical vents, the vent damper may be mounted
with the actuator in any position. On horizontal vents,
do not mount the actuator either directly above or
directly below the vent pipe; mount the vent damper
actuator to the side of the vent.
The vent damper is set up for a continuous pilot sys-
tem. If the vent damper is installed on a system with an
Intermittent Pilot, the energy savings of the vent
damper can be improved by plugging the hole in the
vent damper blade using the knockout plug provided in
the parts envelope.
Closed Position
Hole in Vent Damper Blade
Fig. 8: Vent Damper
DO NOT plug the hole if installing the vent damper on
a continuous pilot system as this will create a haz-
ardous condition.
Fig. 9: Installing The Vent Damper in Horizontal
& Vertical Vents
Fig. 10: D80D General Wiring Diagram
Install the vent damper to service only the single
appliance for which it is intended. If improperly
installed, a hazardous condition, such as an explo-
sion or carbon monoxide poisoning, could result.
Vent Damper peration
For safe, efficient operation, the vent damper and all
flue-product-carrying areas of the appliance must be
checked annually, with particular attention given to
deterioration from corrosion or other sources.
Check vent damper operation as follows:
1. When the boiler is off, check that the vent damper
position indicator points to the closed position (see
Fig. 11).
Damper Position Indicator
Damper Open Damper Closed
Fig. 11: Vent Damper Position Indicator

13
2. Turn the thermostat or controller up to call for heat
and check that the vent damper indicator points to
the open position, as shown in Fig. 11.
3. Turn the thermostat or controller down again and
check that the vent damper position indicator
returns to the closed position.
The vent damper must be inspected at least once
a year by a trained, experienced service techni-
cian. The name of the person who originally
installed your vent damper is shown on the instal-
lation label. Damper must be in open position
when boiler main burners are operating.
Flair Damper
N TE: To place vent damper in the open position to
allow burner operation: Turn the power off. Turn the
damper blade to fully open position (arrow facing
same direction as vent pipe). Turn power on.
SS
R2SS2ES
R
SC
R1
M
2341
JUMPER
GV
24 VAC
TR
HL
L
L12
120 VAC
60Hz
TH
1
Fig. 12: System Schematic
Abbreviation Description
M Damper Motor
R Relay
ES End Switch
SS1 N/C Safety Switch
SS2 N/O Safety Switch
TR Transformer, 120/24V
HL High Limit
V 24V as Valve
TH Thermostat, Heating, Low Voltage
J Jumper
R
24
3JSS HL
GV
1
ES
R
2
SC
M
24 V AC
R
1
SS
2
TH
Fig. 13: Ladder Diagram
Table G: Legend for Figures 12 & 13
Note: Circuit shown with damper in closed position, no call for
heat.

14
VENT DAMPER

15
Gas Supply Connections
The inlet gas connection of the boiler gas valve is 1/2".
Provide an adequate gas piping supply line no smaller
than 1/2", according to Table H above.
as piping must have a sediment trap ahead of the
boiler gas controls, and a manual shut-off valve locat-
ed outside the jacket. All gas piping should be tested
after installation in accordance with local codes.
Model
No.
1/2 in. Pipe 3/4 in. Pipe 1in. Pipe 11/4 in. Pipe
Nat. Pro. Nat. Pro. Nat. Pro. Nat. Pro.
0042 125 350 500
0066 60160 175 460
0090 3080125 300 400
0135 15 40 60 150 200 450
0180 20 35 90 115 300 425
Table H: Maximum Equivalent Pipe Length (Feet)
Sediment Trap Gas Valve
Manual Union
Valve
Fig. 14: Sediment Trap
CAUTI N: The boiler and its manual shut-off valve
must be disconnected from the gas supply during
any pressure testing of that system at test pressures
in excess of 1/2 psi (3.45 kPa). Dissipate test
pressure in the gas supply line before reconnecting
the boiler and its manual shut-off valve to gas supply
line. FAILURE TO FOLLOW THIS PROCEDURE
MAY DAMA E THE AS VALVE. OVER
PRESSURED AS VALVES ARE NOT COVERED
BY WARRANTY. The boiler and its gas connections
shall be leak tested before placing the appliance in
operation. Use soapy water for leak test. DO NOT
use open flame.
N TE: Do not use teflon tape on gas line pipe
thread. A flexible sealant suitable for use with Natural
and Propane gases is recommended.
These boilers are also certified to operate on propane
gas, when equipped with the combination gas valve
and orifices (pilot and main burners) sized for propane
gas.
Gas Pressure
The gas valve is provided with pressure taps to meas-
ure gas pressure upstream of the gas valve and
downstream which is the same as the manifold pres-
sure.
Water Connections & System
Piping
The pipe size for water connections is shown on page
6. Typical piping systems are shown on pages 17 to
19.
This boiler is supplied with a circulator and built-in
bypass as standard to ensure the required minimum
water flow in the boiler. The bypass on models H-0135
and H-0180 is provided with an adjustable valve that is
factory-set in the full open position. The handle is
Gas Type Inches
WC Min.
Inches
WC Max.
Regulator
Setting
Natural 7.0 10.5 3.5
Propane 12.0 13.0 11.0
Table I: Minimum and Maximum Gas Pressure
Must be Supplied by Installer

16
shipped loose. The full open position is appropriate for
most systems, and ensures adequate flow through the
boiler.
If system flow is inadequate, (indicated by excessive
temperature drop through the system) the bypass
valve can be throttled slightly. Care must be taken
against over-throttling which may lead to inadequate
flow through the boiler and boiler harmonics (a hum-
ming sound from the heat exchanger).
If adequate system flow cannot be obtained without
causing harmonics, an additional pump is required.
The factory-mounted circulator will provide adequate
water flow for systems designed at a 20°F temperature
drop, and system pressure drop or head not exceed-
ing that which is shown in Table J.
When the total system head exceeds the available
head pressures, a primary/secondary pumping system
is recommended.
The minimum boiler operating temperature should be
105°F. When operating at low temperature applica-
tions, ∆T (temperature rise) must be 20°F or less.
Propylene glycol solution is commonly used in the
heating system when freeze protection is required.
This will affect the system design and pump perform-
ance. As a rule of thumb, 50% solution of propylene
glycol will require the system flow (gpm) to increase by
14%, and the system head (ft/WC) by 23% in order to
maintain the same heat transfer load.
Model No. System Flow
(gpm)
Max. System
Head (ft/WC)
H-0042 3.5 8.0
H-0066 5.3 8.5
H-0090 7.3 6.5
H-0135 11.0 10.0
H-0180 14.6 7.0
Table : System Pressure Drop
Systems with multiple zones may require an addition-
al circulator. Consult manufacturer's data for valve
pressure drops. When an indirect water heating sys-
tem is used, it is recommended that a separate
circulator be installed to meet the required flow and
pressure drop conditions of the indirect water heater.
We recommend that the make-up water from the cold
water line have a check valve, gate valve, and feedwa-
ter regulator set at 12 psi. Install unions and gate or
ball valves at inlet and outlet connections at the boiler
to facilitate servicing.
The pressure relief valve is mounted on the boiler and
must be piped to a drain. We recommend that all high
points be vented and that purge valves be installed. A
boiler installed above radiation level must be provided
with a low water cut-off device. See page 27 for wiring
hook-up.
The boiler, when used in connection with a refrigera-
tion system, must be installed so that the chilled
medium is piped in parallel with the boiler with appro-
priate valves to prevent the chilled medium from
entering the boiler.
The boiler piping system of a hot water heating boiler,
that is connected to heating coils located in air han-
dling units where they may be exposed to refrigerated
air circulation, must be equipped with flow control
valves or other automatic means to prevent gravity cir-
culation of the boiler water during the cooling cycle.
A diaphragm expansion tank should be installed in the
return line. A typical 8"-diameter expansion tank can
be used on models H-0042, and H-0066, and an 11"-
diameter expansion tank can be used on models
H-0090, H-0135 and H-0180. Consult tank manufac-
turer for correct sizing.

17
Air
Scoop
Air Vent
Diaphragm
Expansion Tank
Feed
Valve Pipe Pressure
ReliefValve
to Drain
Cold Water
Inlet
Heating Units
Fig. 15: Single-Zone Piping
Air
Scoop
Air Vent
Diaphragm
Expansion Tank
Feed
Valve Pipe Pressure
ReliefValve
to Drain
Cold Water
Inlet
Heating Units
Circulators
12” Max.
Fig. 16: Multiple Zones with Circulators
Piping Diagrams

18
Electrical Wiring
The electrical power supply requirement for these boil-
ers is 120 VAC, 60 Hz. Field wiring connections and
electrical grounding must comply with the local codes,
or in the absence of local codes, with the latest edition
of the National Electrical Code, ANSI/NFPA 70.
Provide a separate fused circuit from the main electri-
cal panel to the boiler, and a disconnecting means
within sight of the boiler.
Remove the control box cover and make the power
supply connections in the field wiring compartment.
(See general location of controls drawing on page 28).
The pump is supplied and factory-wired to operate
with the boiler. The "TH" wire leads are for the room
thermostat or zone valve connections.
The room thermostat should be installed in accor-
dance with the manufacturer's instructions. The
thermostat heat anticipator should be set at 1.0
ampere (automatic ignition) and 0.60 ampere (stand-
ing pilot) for single- zone installations. For multi-zone
applications, the heat anticipator setting should be
based on the ampere load in the thermostat circuit.
N TE: If it is necessary to replace any of the
original wiring, it must be replaced with 105°C wire or
its equivalent, except 150°C black wire must be
replaced with 150°C wire or its equivalent. See Fig.
19 for 150°C wire indication.

19
Wiring Diagrams

20