U.S. Boiler Company RSAH Series Service manual

110891-02 - 5/22
RSAH
Models:
• RSAH111E
• RSAH111E-T
• RSAH154E
• RSAH154E-T
•Natural Draft
• Oil-Fired
•Water Boiler
•B20 Ready
TO THE INSTALLER:
Affix these instructions adjacent to boiler.
TO THE CONSUMER:
Retain these instructions for future reference.
For service or repairs to boiler, call your heating contractor. When seeking information on boiler, provide
Boiler Model Number and Serial Number as shown on Rating Label.
Installation, Operating and Service Instructions for
Manual Contents Page
1. General Information ......................5
2. Pre-Installation ..........................7
3. Water Piping and Trim....................10
4. Venting ...............................15
5. Electrical ..............................17
6. OIl Piping..............................20
7. System Start-Up ........................22
8. Operating..............................28
9. Maintenance & Service Instructions ........32
10. Boiler Cleaning .........................34
11. Troubleshooting ........................37
12. Service Parts...........................42

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IMPORTANT INFORMATION - READ CAREFULLY
All boilers must be installed in accordance with National, State and Local Plumb-All boilers must be installed in accordance with National, State and Local Plumb-
ing, Heating and Electrical Codes and the regulations of the serving utilities. Theseing, Heating and Electrical Codes and the regulations of the serving utilities. These
Codes and Regulations may differ from this instruction manual. Authorities havingCodes and Regulations may differ from this instruction manual. Authorities having
jurisdiction should be consulted before installations are made.jurisdiction should be consulted before installations are made.
In all cases, reference should be made to the following Standards:In all cases, reference should be made to the following Standards:
The following terms are used throughout this manual to bring attention to the presence of hazards
of various risk levels, or to important information concerning product life.
IMPORTANT
This boiler is equipped with a feature that saves energy by reducing the boiler water temperature as the heating
load decreases. This feature is equipped with an override which is provided primarily to prevent the use of external
energy management system that serves the same function. THIS OVERRIDE MUST NOT BE USED UNLESS AT
LEAST ONE OF THE FOLLOWING CONDITIONS IS TRUE:
•An external energy management system is installed that reduces the boiler water temperature as the heating load
decreases.
•This boiler is not used for any space heating.
•This boiler is part of a modular or multiple boiler system having a total input of 300,000 BTU/HR or greater.
•This boiler is equipped with a tankless coil.
USA BOILERSUSA BOILERS
A. Current Edition of American National Standard ANSI/NFPA 31, “Installation of OilA. Current Edition of American National Standard ANSI/NFPA 31, “Installation of Oil
Burning Equipment”, for recommended installation practices.Burning Equipment”, for recommended installation practices.
B. Current Edition of American National Standard ANSI/NFPA 211, “Chimneys, FireB. Current Edition of American National Standard ANSI/NFPA 211, “Chimneys, Fire
places, Vents, and Solid Fuel Burning Appliances”, For Venting requirements.places, Vents, and Solid Fuel Burning Appliances”, For Venting requirements.
C. Current Edition of American Society of Mechanical Engineers ASME CSD-1,C. Current Edition of American Society of Mechanical Engineers ASME CSD-1,
“Controls and Safety Devices for Automatically Fired Boilers”, for assembly and“Controls and Safety Devices for Automatically Fired Boilers”, for assembly and
operations of controls and safety devices.operations of controls and safety devices.
D. All wiring on boilers installed in the USA shall be made in accordance with theD. All wiring on boilers installed in the USA shall be made in accordance with the
National Electrical Code and/or Local Regulations.National Electrical Code and/or Local Regulations.
NOTICE: This boiler has a limited warranty, a copy of which is included with this boiler. The warranty for this boiler
is valid only if the boiler has been installed, maintained and operated in accordance with these instructions.
Surface rust on cast iron sections may be attributed to the manufacturing process as well as condensation
during storage. Surface rust is normal and does not affect the performance or longevity of a boiler.
NOTICE: Indicates special instructions on
installation, operation, or maintenance which
are important but not related to personal injury
hazards.
DANGER
Indicates an imminently hazardous situation
which, if not avoided, will result in death, serious
injury or substantial property damage.
CAUTION
Indicates a potentially hazardous situation
which, if not avoided, may result in moderate or
minor injury or property damage.
WARNING
Indicates a potentially hazardous situation
which, if not avoided, may result in moderate or
minor injury or property damage.
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DANGER
DO NOT store or use gasoline or other flammable vapors or liquids in the vicinity of this or any other
appliance.
!
WARNING
Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal
injury or loss of life. Failure to follow all instructions in the proper order can cause personal injury or death.
Read and understand all instructions, including all those contained in component manufacturers manuals
which are provided with the boiler before installing, starting-up, operating, maintaining or servicing this boiler.
Keep this manual and literature in legible condition and posted near boiler for reference by owner and service
technician.
• This boiler requires regular maintenance and service to operate safely. Follow the instructions contained in this
manual.
• Installation, maintenance, and service must be performed only by an experienced, skilled and knowledgeable
installer or service agency.
• All heating systems should be designed by competent contractors and only persons knowledgeable in the
layout and installation of hydronic heating systems should attempt installation of any boiler.
• Installation is NOT complete unless a pressure relief valve is installed into the tapping located on top of Shell
Assembly in the front left corner - See Water Piping and Trim Section of this manual for additional details.
• It is the responsibility of the installing contractor to see that all controls are correctly installed and are operating
properly when installation is complete including verifying that the limit sensor is fully installed (seated in bottom
of Well).
• Failure to properly install Limit Sensor may result in property damage, personal injury or loss of life due to
elevated operating temperatures and/or pressures.
• This boiler is NOT suitable for installation on combustible flooring. DO NOT operate boiler on combustible
flooring without factory supplied floor shield (available option at extra cost). A concrete pad is NOT sufficient
to protect combustible flooring. Concrete over wood joists is considered combustible flooring.
• DO NOT install boiler on carpeting.
• When boiler is installed on concrete which is over a material that is subject to melting (PVC, PEX radiant
tubing, etc.) a combustible floor shield must be used.
• DO NOT operate on masonry floors, which may contain moisture.
• DO NOT tamper with or alter the boiler or controls.
• Retain your contractor or a competent serviceman to assure that the unit is properly adjusted and maintained.
• Have Firetubes cleaned at least once a year - preferably at the start of the heating season to remove soot and
scale. The inside of combustion chamber should also be cleaned and inspected at the same time.
• When cleaning this boiler, DO NOT damage combustion chamber. If damaged, combustion chamber must be
replaced immediately.
• Oil Burner and Controls must be checked at least once a year or as may be necessitated.
• DO NOT operate boiler with jumpered or absent controls or safety devices.
• DO NOT operate boiler if any control, switch, component, or device has been subject to water.
• Boiler materials of construction, products of combustion and the fuel contain alumina, silica, heavy metals,
carbon monoxide, nitrogen oxides, aldehydes and/or other toxic or harmful substances which can cause
death or serious injury and which are known to the state of California to cause cancer, birth defects and other
reproductive harm. Always use proper safety clothing, respirators and equipment when servicing or working
nearby the boiler.
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RSAH Installation & Service Manual
WARNING
This boiler contains very hot water under 12 - 15 PSI pressure. DO NOT unscrew any pipe fittings nor attempt
to disconnect any components of this boiler without positively assuring the water is cool and has no pressure.
Always wear protective clothing and equipment when installing, starting up or servicing this boiler to prevent
scald injuries. DO NOT rely on the pressure and temperature gauges to determine the temperature and
pressure of the boiler. This boiler contains components which become very hot when the boiler is operating.
DO NOT touch any components unless they are cool.
• High water temperatures increase the risk of scalding injury. If this boiler is equipped with a tankless heater
for domestic water supply, a flow regulator and automatic mixing valve must be installed properly in tankless
heater piping. See Piping and Trim Sections of this manual for details.
• This boiler needs fresh air for safe operation and must be installed so there are provisions for adequate
combustion and ventilation air.
•This boiler must be connected to an approved chimney or vent system in good condition. Serious property
damage could result if the boiler is connected to a dirty or inadequate chimney or vent system. The
interior of the chimney flue must be inspected and cleaned before the start of the heating season for any
obstructions. A clean and unobstructed chimney flue is necessary to allow noxious fumes that could cause
injury or loss of life to vent safely and will contribute toward maintaining the boiler’s efficiency. DO NOT
operate boiler with the absence of an approved vent system.
• This boiler is supplied with controls which may cause the boiler to shut down and not re-start without
service. If damage due to frozen pipes is a possibility, the heating system should not be left unattended in
cold weather; or appropriate safeguards and alarms should be installed on the heating system to prevent
damage if the boiler is inoperative.
• This boiler is designed to burn No. 2 fuel oil including bio blends not exceeding 20% Bio Diesel (ASTM
D396) only.
• DO NOT USE with Flammable Liquids, Gasoline, Crankcase drainings, charcoal lighter fluid, or any oil
containing gasoline.
• DO NOT convert to any solid fuel (i.e., wood, coal).
• DO NOT convert to any gaseous fuel (i.e., natural gas, LP).
• DO NOT USE Raw Vegetable Oil (RVO) or any fuel blended with RVO
• Use of untested/uncertified fuels could result in explosion, fire, personal injury, or death, and/or damage
to equipment and property.
• Never burn garbage or paper in this boiler.
• All flammable debris, rags, paper, woodscraps, etc., should be kept clear of the boiler at all times. Keep the
boiler area clean and free of fire hazards.
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Figure 1-1: RSAH Series Boiler Dimensional Data
Boiler Model Number Dimension
‘A’
Water Capacity
(gallons)
Approx.
Shipping Weight (lb.)
RSAH111E(-T) 34-9/16 10.1 300
RSAH154E(-T) 41 in. 15.4 355
Note: Maximum Working Pressure: Water 30 PSI shipped standard.
Table 1-2: Dimensional D (See Figure 1-1)
1General Information

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RSAH Installation & Service Manual
Table 1-3: Rating Data
Boiler Model
No.
Burner Capacity DOE Heating
Capacity -
MBH
(2)
AHRI NET
Ratings
- MBH
(3)
AFUE %
Minimum Chimney Requirements
GPH MBH
(1)
Round In.
Dia.
Rectangle
In. x In. Height Ft.
RSAH111E(-T) 0.75 110 95 83 86.2 6 8 x 8 15
RSAH154E(-T) 1.10 154 139 117 86.0 6 8 x 8 15
(1) MBH refers to thousands of BTU per hour
(2) Based on Standard Test prescribed by the United States Department of Energy at combustion conditions of 13.0% CO2
(3) Net AHRI rating based on a piping and pickup allowance of 1.15.
1General Information (continued)
Note: The rating shown are based on the use of #2 Heating Oil.

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A. INSPECT SHIPMENT carefully for any signs of
damage.
1. All equipment is carefully manufactured,
inspected and packed. Our responsibility
ceases upon delivery of crated boiler to the
carrier in good condition.
2. Any claims for damage or shortage in
shipment must be filed immediately against the
carrier by the consignee. No claims for
variances from, or shortage in orders, will be
allowed by the manufacturer unless presented
within sixty (60) days after receipt of goods.
B. LOCATE BOILER near final position before
removing crate. See Figure 1-1. Using hand
truck or pipe rollers under skid, move boiler into
position along side installation site.
CAUTION
DO NOT drop boiler. DO NOT bump boiler
jacket against floor.
1. LOCATE so that vent pipe connection to
chimney will be short and direct.
2. BOILER IS NOT SUITABLE FOR
INSTALLATION ON COMBUSTIBLE FLOOR
without factory supplied floor shield (available
option at extra cost), see Page 9 for additional
details. A Combustible Floor Shield can also
be constructed in accordance with NFPA 31.
DO NOT install boiler on carpeting.
3. FOR BASEMENT INSTALLATION, provide a
solid elevated base, such as concrete, if floor
is not level, or if water may be encountered on
floor around boiler.
WARNING
DO NOT support boiler by placing blocks at the
four (4) corners of the boiler.
Boiler base must be evenly supported under
entire base.
Concrete over wood joists is considered
combustible flooring. DO NOT operate on
masonry floors, which may contain moisture.
4. PROVIDE SERVICE CLEARANCE of at least
48” clearance from front jacket panel for
servicing burner and removal of front tankless
heater.
5. For minimum clearances to combustible
materials. See Figure 2-1.
NOTICE: Clearance to venting is for single wall
vent pipe. If Type L vent is used, clearance may
be reduced to the minimum required by the vent
pipe manufacturer.
Figure 2-1: Minimum Clearances to Combustible Materials
NOTE 1: Listed clearances comply with American National
Standard NFPA 31, Standard for the Installation of Oil
Burning Equipment.
NOTE 2: RSAH Series boilers can be installed in rooms
with clearances from combustible material as listed above.
Listed clearances cannot be reduced for alcove or closet
installations.
NOTE 3: For reduced clearances to combustible material,
protection must be provided as described in the ANSI/NFPA
31 standard.
C
A
Above
B
Front
Chimney
Connector
D
Rear
E
Sides
18 48 18 18 18
2Pre-Installation
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C. REMOVE CRATE
1. Remove all fasteners at crate skid.
2. Lift outside container and remove all other
inside protective spacers and bracing.
Remove accessory parts carton.
D. REMOVE BOILER FROM SKID
1. Remove four (4) hex head lag screws,
attaching boiler base plate to shipping skid.
2. Carefully, walk boiler to the edge of the skid.
Tilt the boiler back, allowing boiler base edge
to rest on the floor, then, remove the skid.
3. Position boiler for final installation.
E. PROVIDE COMBUSTION AND VENTILATION AIR.
Local code provisions may apply and should be
referenced.
WARNING
Adequate combustion and ventilation air must
be provided to assure proper combustion and
to maintain safe ambient air temperatures.
DO NOT install boiler where gasoline or other
flammable vapors or liquids, or sources of
hydrocarbons (i.e. bleaches, fabric softeners,
etc.) are used or stored.
1. Determine volume of space (boiler room).
Rooms communicating directly with the space
in which the appliances are installed, through
openings not furnished with doors, are
considered a part of the space.
Volume(ft.3) = Length(ft.) x Width(ft.) x
Height(ft.)
2. Determine total input of all appliances in the
space.
Add inputs of all appliances in the space and
round the result to the nearest 1000 BTU per
hour.
3. Determine type of space. Divide Volume by
total input of all appliances in space. If the
result is greater than or equal to 50 ft3/1000
BTU per hour, then it is considered an
unconfined space. If the result is less than 50
ft3/1000 BTU per hour then the space is
considered a confined space.
4. For boiler located in an unconfined space of a
conventionally constructed building, the fresh
air infiltration through cracks around windows
and doors normally provides adequate air for
combustion and ventilation.
5. For boiler located in a confined space or an
unconfined space in a building of unusually
tight construction, provide outdoor air with the
use of two permanent openings which
communicate directly or by duct with the
outdoors or spaces (crawl or attic) freely
communicating with the outdoors. Locate one
opening within 12 inches of top of space.
Locate remaining opening within 12 inches of
bottom of space. Minimum dimension of air
opening is 3 inches. Size each opening per
following:
a. Direct communication with outdoors.
Minimum free area of 1 square inch per
4,000 BTU per hour input of all equipment in
space.
b. Vertical ducts. Minimum free area of 1
square inch per 4,000 BTU per hour input of
all equipment in space. Duct cross-
sectional area shall be same as opening
free area.
c. Horizontal ducts. Minimum free area of 1
square inch per 2,000 BTU per hour input of
all equipment in space. Duct cross-
sectional area shall be same as opening
free area.
Alternate method for boiler located within
confined space.Use indoor air if two
permanent openings communicate directly
with additional space(s) of sufficient volume
such that combined volume of all spaces
meet criteria for unconfined space. Size
each opening for minimum free area of 1
square inch per 1,000 BTU per hour input of
all equipment in spaces, but not less than
100 square inches.
6. Louvers and Grilles of Ventilation Ducts
a. All outside openings should be screened
and louvered. Screens used should not be
smaller than 1/4 inch mesh. Louvers will
prevent the entrance of rain and snow.
b. Free area requirements need to consider
the blocking effect of louvers, grilles, or
screens protecting the openings. If the free
area of the louver or grille is not known,
assume wood louvers have 20-25 percent
free area and metal louvers and grilles have
60-75 percent free area.
c. Louvers and grilles must be fixed in the
open position, or interlocked with the
equipment to open automatically during
equipment operation.
2Pre-Installation (continued)
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INSTALLATION INSTRUCTIONS FOR OPTIONAL SHIELD REQUIRED
FOR COMBUSTIBLE FLOOR
This shield for combustible floors is intended for use only with the following U.S. Boiler Company oil-fired boilers:
Use Part Number 6183504 for the following models:
RSAH111E(-T) RSAH154E(-T)
ADDS 4-3/16” TO BOILER HEIGHT
1. Place shield on combustible floor with “TOP”
surface upward and “FRONT” surface directly
below the expected position of the oil burner.
2. Locate shield such that clearances to combustible
walls are as indicated in Figure 2-2. These
dimensions will assure that the boiler jacket will be
at least 18 in. from the side and rear walls and 48
in. from the front wall, as required by ANSI/NFPA
31.
3. Fasten shield to combustible floor to keep shield
from shifting position during setting of boiler.
4. Set boiler squarely on top of shield such that
base plate of boiler rests flat on top surface of
shield and does not over-hang shield on any side.
Confirm clearance to combustible walls. Refer to
Figure 2-1.
5. DO NOT enclose boiler (including shield) on all
four sides. Boiler may be enclosed on any three
sides while maintaining minimum clearances
shown in Figure 2-1 for each of those three sides.
Figure 2-2: Floor Shield
2Pre-Installation (continued)

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Figure 3-1: Recommended Piping for Combination
Heating and Cooling (Refrigeration) System
A. DESIGN A PIPING SYSTEM and install boiler
which will prevent oxygen contamination of boiler
water and frequent water additions.
1. There are many possible causes of oxygen
contamination such as:
a. Addition of excessive make-up water as a
result of system leaks.
b. Absorption through open tanks and fittings.
c. Oxygen permeable materials in the
distribution system.
2. In order to insure long product life, oxygen
sources should be eliminated. This can be
accomplished by taking the following
measures:
a. Repairing system leaks to eliminate the
need for addition of make-up water.
b. Eliminating open tanks from the system.
c. Eliminating and/or repairing fittings which
allow oxygen absorption.
d. Use of non-permeable materials in the
distribution system.
e. Isolating the boiler from the system water by
installing a heat exchanger.
3. Connect System supply and return piping to
boiler. See Figures 3-3 and 3-4. Also, consult
I=B=R, “Residential Hydronic Heating
Installation and Design Guide”. Maintain
minimum ½ inch clearance from hot water
piping to combustible materials.
WARNING
System supply and return piping must be
connected to correct boiler pipe.
U.S. Boiler Company recommends sizing the
system circulator to supply sufficient flow (GPM)
to allow a 20°F temperature differential in the
system. When sizing the system circulator, the
pressure drop of all radiators, baseboard and
radiant tubing and all connecting piping must
be considered.
a. If this boiler is used in connection with
refrigeration systems, the boiler must be
installed so that the chilled medium is piped
in parallel with the heating boiler using
appropriate valves to prevent the chilled
medium from entering the boiler. See Figure
3-1. Also, consult I=B=R, “Residential
Hydronic Heating Installation and Design
Guide”.
b. If this boiler is connected to heating coils
located in air handling units where they may
be exposed to refrigerated air, the boiler
piping must be equipped with flow control
valves to prevent gravity circulation of boiler
water during the operation of the cooling
system.
c. If boiler is used with an Indirect-Fired
Domestic Water Heater, install the Indirect-
Fired Domestic Water Heater as a separate
heating zone. Refer to the Indirect-Fired
Domestic Water Heater Installation,
Operating, and Service Instructions for
additional information.
3Water Piping and Trim
!
WARNING
Failure to properly pipe boiler may result in improper operation and damage to boiler or structure.
Oxygen contamination of boiler water will cause corrosion of iron and steel boiler components, and can
lead to boiler failure. -U.S.Boiler Company’s Standard Warranty does not cover problems caused by oxygen
contamination of boiler water or scale (lime) build-up caused by frequent addition of water.
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d. Use a system bypass if the boiler is to be
operated in a system which has a large
volume or excessive radiation where low
boiler water temperatures may be
encountered (i.e. converted gravity
circulation system, etc.) The bypass should
be the same size as the supply and return
lines with valves located in the bypass and
return line as illustrated in Figures 3-3 and
3-4 in order to regulate water flow for
maintenance of higher boiler water
temperature. Set the bypass and return
valves to a half throttle position to start.
Operate boiler until the system water
temperature reaches its normal operating
range. Adjust the valves to maintain 180°F
to 200°F boiler water temperature and
greater the 120°F return temperature.
Adjust both valves simultaneously. Closing
the boiler return valve while opening the
bypass valve will raise the boiler return
temperature. Opening the boiler return
valve while closing the by-pass valve will
lower the boiler return temperature.
e. A water boiler installed above radiation level
must be provided with a low water cutoff
device as part of the installation.
B. INSTALL SAFETY RELIEF VALVE. See Figures
3-2, 3-3 and 3-4. Safety Relief Valve must be
installed with spindle in the vertical position.
Installation of the relief valve must be consistent
with ANSI/ASME Boiler and Pressure Vessel Code,
Section IV.
WARNING
Installation is NOT complete unless a safety
relief valve is installed as shown in Figure 5.
Safety (relief) valve discharge piping must
be piped near floor to eliminate potential of
severe burns. DO NOT pipe in any area where
freezing could occur. DO NOT install any shut-
off valves, plugs or caps.
C. AIR VENT. An air vent or purge must be
incorporated in the system to easily remove air
from the boiler when the system is filled. The
boiler has a built in dip tube which works with
the air vent to clear the boiler of air. Improper
application of the air vent will cause steaming in
the boiler. See Figures 3-2, 3-3 and 3-4.
D. INSTALL DRAIN VALVE in return piping. See
Figures 3-3 and 3-4.
E. OIL, GREASE, AND OTHER FOREIGN
MATERIALS which accumulate in new hot
water and a new or reworked system should
be boiled out, and then thoroughly flushed. A
qualified water treatment chemical specialist
should be consulted for recommendations
regarding appropriate chemical compounds and
concentrations which are compatible with local
environmental regulations.
Figure 3-2: Air Vent and Safety Relief Valve
Installation Detail
F. AFTER THE BOILER AND SYSTEM HAVE BEEN
CLEANED and flushed, and before refilling the
entire system add appropriate water treatment
chemicals, if necessary, to bring the pH between
7 and 11.
G. CONNECT TANKLESS HEATER PIPING AS
SHOWN IN FIGURE 3-5. See Table 3-6 for
Tankless Heater Rating.
WARNING
Install automatic mixing valve at tankless heater
outlet to avoid risk of burns or scalding due
to excessively hot water at fixtures. Adjust
and maintain the mixing valve in accordance
with the manufacturer’s instructions. DO NOT
operate tankless heater without mixing valve.
3Water Piping and Trim (continued)
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Figure 3-3: Recommended Boiler Piping for Circulator Zoned Heating Systems, Supply Side Circulator
3Water Piping and Trim (continued)

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Figure 3-4: Boiler Piping for Zone Valve Zoned Heating Systems, Supply Side Circulator
3Water Piping and Trim (continued)

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RSAH Installation & Service Manual
Figure 3-5: Schematic Tankless Heater Piping
Table 3-6: Tankless Heater Ratings
dishwashers and automatic washers is
possible by piping the hot water from the
heater prior to entering the mixing valve. The
mixing valve should be “trapped” by installing
it below the cold water inlet to heater to prevent
lime formation in the valve. Refer to Figure 3-5.
3. FLUSHING OF HEATER — All water contains
some sediment which settles on the inside of
the coil. Consequently, the heater should be
periodically backwashed. This is accomplished
by installing hose bibs as illustrated and
allowing water at city pressure to run into hose
bib A, through the heater, and out hose bib B
until the discharge is clear. The tees in which
the hose bibs are located should be the same
size as heater connections to minimize
pressure drop.
4. HARD WATER — A water analysis is
necessary to determine the hardness of your
potable water. This is applicable to some city
water and particularly to well water. An
appropriate water softener should be installed
based on the analysis and dealer’s
recommendation. This is not only beneficial to
the tankless heater but to piping and fixtures
plus the many other benefits derived from soft
water.
Boiler Model
Tankless Heater Model
S-5A
GPM PSID
RSAH111E(-T) 3½ 15
RSAH154E(-T) 3¾ 25
3Water Piping and Trim (continued)
THE FOLLOWING GUIDELINES SHOULD BE
FOLLOWED WHEN PIPING THE TANKLESS HEATER:
1. FLOW REGULATION — If flow through the
heater is greater than its rating, the supply of
adequate hot water may not be able to keep
up with the demand. For this reason a flow
regulator matching the heater rating should be
installed in the cold water line to the heater.
The flow regulator should preferably be located
below the inlet to the heater and a minimum of
3’ away from the inlet so that the regulator is
not subjected to excess temperatures that may
occur during “off” periods when it is possible
for heat to be conducted back through the
supply line. The flow regulator also limits the
flow of supply water regardless of inlet
pressure variations in the range of 20 to 125
psi.
2. TEMPERING OF HOT WATER — Installation of
an automatic mixing valve will lengthen the
delivery of the available hot water by mixing
some cold water with the hot. This prevents the
possibility of scalding hot water at the fixtures.
In addition, savings of hot water will be
achieved since the user will not waste as much
hot water while seeking a water temperature.
Higher temperature hot water required by

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A. GENERAL GUIDELINES.
1. Vent system installation must be in accordance
with these instructions and applicable
provisions of local building codes. Contact
local building or fire officials about restrictions
and installation inspection in your area.
2. The RSAH Series is designed to be vented into
a fireclay tile-lined masonry chimney or
chimney constructed from type-L vent or a
factory built chimney that complies with the
type HT requirements of UL103. The chimney
or vent pipe shall have a sufficient draft at all
times, to assure safe proper operation of the
boiler. See Figure 8 for recommended
installation.
a. Install a draft regulator (supplied by
installer) following the instructions furnished
with the regulator. See Figure 4-2 for
alternate regulator locations.
b. With any new or replacement installation the
chimney has to be considered. Chimneys
that have a high heat loss become less
suitable as the heat loss of the home goes
down and the efficiency of the boiler goes
up. Most homes have a chimney
appropriate for the fuel and the era in which
the home was built. That may have been a
coal fired or an inefficient oil fired boiler built
into a home without insulation or storm
windows. With increasing fuel prices that
home probably has been insulated and
fitted with storm windows so that the heat
loss of the home has been reduced. This
requires less fuel to be burned and sends
less heat up the chimney.
A new boiler probably has a higher
efficiency than the boiler being replaced.
That probably means that the stack
temperature from the new boiler will be
lower than that from the old boiler and with
less room air being drawn up the chimney
to dilute the stack gases. The combination
of a large uninsulated chimney, reduced
firing rate, reduced firing time, lower stack
temperature and less dilution air can, in
some cases, contribute to the condensing
of small amounts of water vapor in the
chimney. Such condensation, when it
occurs, can cause chimney deterioration.
In extreme cases, the chimney may have to
be lined to insulate the chimney and thus
prevent the condensation. The addition of
dilution air into the chimney may assist in
drying the chimney interior surfaces.
A massive chimney on a cold, or exposed
outside wall may have produced adequate
draft when it was fired with a higher input
and greater volumes of heated gases. With
reduced input and volume, the draft may be
severely affected. In one instance our
research showed a new chimney of
adequate sizing produced only -.035” W.C.
after 30 minutes of continuous firing at
13.0% CO2. Outside wall chimneys take
longer to heat up and can have .00” W.C.
draft at burner start-up. You may have to
consider a special alloy chimney flue liner
with insulation around it and stabilizing draft
cap or even a draft inducing fan in severe
cases.
c. For the same reasons as in (2.) above, heat
extractors mounted into the breeching are
not recommended.
3. For minimum clearances to combustible
materials refer to Figure 2-1.
4Venting

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Figure 4-1: Recommended Smokepipe Arrangement and Chimney Requirements
Figure 4-2: Draft Regulator Locations
4Venting (continued)

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A. GENERAL
1. Install wiring and electrically ground boiler in
accordance with requirements of the authority
having jurisdiction, or in absence of such
requirements the National Electrical Code,
ANSI/NFPA 70, and/or the CSA C22.1 Electric
Code.
2. A separate electrical circuit must be run from
the main electrical service with an over-current
device/disconnect in the circuit. A service
switch is recommended and may be required
by some local jurisdictions.
3. Wiring should conform to Figure 5-1.
B. SYSTEM CONTROLS AND WIRING
1. Refer to National Electric Code or Local
Electric Codes for proper size and type of wire
required. Follow Code.
2. Use anti-short bushings on all wiring passing
through boiler jacket, junction boxes and/or
control boxes.
3. Use armored cable (BX) over all exposed line
voltage wiring.
4. If an indirect water heater is used, use priority
zoning. DO NOT use priority zoning for
Hydro-Air Systems.
5. Single Zone System – Refer to Figure 5-1 for
the electrical diagram for this type of system.
Connect the system circulator wire leads to the
proper locations on the control. See Figure
5-1.
C. INSTALL A ROOM THERMOSTAT on an
inside wall about four feet above floor. Never
install thermostat on an outside wall or where
it will be influenced by drafts, hot or cold water
pipes, lighting fixtures, television, rays of the sun
or near a fireplace. Keep large furniture away from
thermostat so there will be free movement of room
air around this control.
Connect the thermostat to the ‘T-T’ terminals on
the control.
WARNING
The maximum allowable current for each
circulator is 5 amps at 120V AC. For circulators
with higher amp ratings, you must install a
circulator relay or starter coil to provide line
voltage to the circulator and connect only the
relay or starter coil to boiler terminals. The
combined boiler and circulator amperage must
not exceed 15 amps.
Install over-current protection in accordance
with authority having jurisdiction or, in the
absence of such requirements, follow the
National Electric Code, NFPA 70, and/or CSA
C22.1 Electrical Code. DO NOT provide over-
current protection greater than 15 amperes.
DANGER
Positively assure all electrical connections are unpowered before attempting installation or service of
electrical components or connections of the boiler or building. Lock out all electrical boxes with padlock
once power is turned off.
WARNING
•Failure to properly wire electrical connections to the boiler may result in serious physical harm.
• Electrical power may be from more than one source. Make sure all power is off before attempting any
electrical work.
• Each boiler must be protected with a properly sized fused disconnect.
• Never jump out or make inoperative any safety or operating controls.
• The wiring diagrams contained in this manual are for reference purposes only. Refer to the wiring diagram
of any controls used with the boiler. Read, understand and follow all wiring instructions supplied with the
controls.
!
!
5Electrical
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Figure 5-1: Schematic Wiring Diagram
5Electrical (continued)
Figure 5-2: Schematic Wiring Diagram

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5Electrical (continued)
Figure 5-2: Schematic Wiring Diagram

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A. GENERAL.
1. Use flexible oil line(s) so that burner can be
removed without disconnecting the oil supply.
2. A supply line fuel oil filter is recommended as a
minimum for all firing rates but a pleated paper
fuel oil filter is recommended for the lowest
firing rate application to prevent nozzle fouling.
Figure 6-1: Single-Pipe Installation
3. Use Flared fittings only. DO NOT use
compression fittings.
4. Use of a high efficiency micron filter (Garber or
equivalent) in addition to conventional filter is
highly recommended.
B. SINGLE-PIPE OIL LINES.
1. Standard burners are provided with single-
stage 3450 rpm fuel units with the bypass plug
removed for single-pipe installations.
2. The single-stage fuel unit may be installed
single-pipe with gravity feed or lift. Maximum
allowable lift is 8 feet. See Figure 6-1.
NOTICE: Oil piping must be absolutely airtight or
leaks or loss of prime may result. Bleed line and
fuel unit completely.
6Oil Piping
NOTICE: The National Oilheat Research Alliance
(NORA) recommends single pipe oil systems and
high-quality filtration for all fuel types. This should
include at least a 10-micron Spin-on filter. Double
filtration provides even greater assurance clean
fuel will get to the pump. Contaminants in the tank
that enter the fuel supply to the burner can cause
pump sticking/seizing. These contaminants may
increase in the early stages of transitioning to
modern fuels (Ultra Low Sulfur and Bio Blends).
High quality filtration adds protection against
pump sticking.