New Yorker AP-490U Service manual

INSTALLATION, OPERATING
AND SERVICE INSTRUCTIONS
AP-U™ SERIES
STEEL OIL-FIRED BOILER
104338-03 - 12/13 Price - $5.00
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.
Boiler Model Number
AP- U
Boiler Serial Number Installation Date
Heating Contractor Phone Number
Address

2
IMPORTANT INFORMATION - READ CAREFULLY
All boilers must be installed in accordance with National, State and Local Plumbing, Heating
and Electrical Codes and the regulations of the serving utilities. These Codes and Regulations
may differ from this instruction manual. Authorities having jurisdiction should be consulted
before installations are made.
In all cases, reference should be made to the following Standards:
USA BOILERS
A. Current Edition of American National Standard ANSI/NFPA 31, “Installation of Oil
Burning Equipment”, for recommended installation practices.
B. Current Edition of American National Standard ANSI/NFPA 211, “Chimneys, Fireplaces,
Vents, and Solid Fuel Burning Appliances”, For Venting requirements.
C. Current Edition of American Society of Mechanical Engineers ASME CSD-1, “Controls and
Safety Devices for Automatically Fired Boilers”, for assembly and operations of controls
and safety devices.
D. All wiring on boilers installed in the USA shall be made in accordance with the National
Electrical Code and/or Local Regulations.
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, could result in death, serious injury
or substantial property damage.
NOTICE
Indicates special instructions on installation,
operation, or maintenance which are important
but not related to personal injury hazards.
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.
NOTICE
This boiler has a limited warranty, a copy of which is printed on the back of this manual.
The warranty for this boiler is valid only if the boiler has been installed, maintained and operated in
accordance with these instructions.

3
DANGER
DO NOT store or use gasoline or other ammable 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 con-
tained 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 ooring. DO NOT operate boiler on
combustible ooring without factory supplied oor shield (available option at extra cost). A concrete
pad is NOT sufcient to protect combustible ooring. Concrete over wood joists is considered
combustible ooring.
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 oor shield must be used.
DO NOT operate on masonry oors, 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.

4
TABLE OF CONTENTS
I. General Information................................5
II. Pre-Installation........................................7
III. Water Piping and Trim ..........................10
IV. Venting ..................................................15
V. Electrical................................................17
VI. Oil Piping..............................................21
VII. System Start-Up.....................................23
VIII. Operating ..............................................31
IX. Maintenance & Service Instructions......36
X. Boiler Cleaning .....................................38
XI. Troubleshooting ....................................40
XII. Repair Parts...........................................44
XIII. Beckett AFG Burner Parts for
AP-U™ Series Boilers .............................48
XIV. Riello Burner Parts for
AP-U™ Series Boilers .............................50
Appendix A - Low Water Cut O...........51
WARNING
This boiler contains very hot water under 12 - 15 PSI pressure. DO NOT unscrew any pipe ttings 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 ow regulator and automatic mixing valve must be installed properly
in tankless heater piping. See Water Piping and Trim Section 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 ue must be inspected and cleaned before the start of the heating season for
any obstructions. A clean and unobstructed chimney ue 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 efciency.
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 only. DO NOT use gasoline, crankcase drainings, or any
oil containing gasoline. Never burn garbage or paper in this boiler. DO NOT convert to any solid fuel
(i.e. wood, coal). DO NOT convert to any gaseous fuel (i.e. natural gas, LP). All ammable debris, rags,
paper, wood scraps, etc., should be kept clear of the boiler at all times. Keep the boiler area clean and
free of re hazards.

5
Figure 1: AP-U Series Boiler Dimensional Data
Boiler Model Number Dimension
‘A’
Water Capacity
(gallons)
Approx.
Shipping Weight (lb.)
AP-490U 34-9/16 10.7 290
AP-590U 10.1 300
AP-690U 41” 16.3 340
AP-790U 15.4 355
Note: Maximum Working Pressure: Water 30 PSI shipped standard.
I: GENERAL INFORMATION
TABLE 1: DIMENSIONAL DATA (See Figure 1)

6
I: GENERAL INFORMATION (continued)
TABLE 2: RATING DATA
Boiler Model
No.
Burner Capacity DOE Heating
Capacity -
MBH
AHRI NET
Ratings -
MBH
Minimum Chimney Requirements AFUE %
GPH MBH Round In.
Dia.
Rectangle
In. x In. Height Ft.
AP-490U 0.75 105 88 77 6 8 x 8 15 84
AP-590U 1.00 140 119 103 6 8 x 8 15 84
AP-690U 1.10 154 131 114 6 8 x 8 15 84
AP-790U 1.35 189 160 139 7 8 x 8 15 84
Boiler Model Sufx: P = Packaged

7
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 led 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 nal position before removing
crate. See Figure 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 oor.
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 oor shield (available
option at extra cost), see Page 9 for additional
details. A Combustible Floor Shield can also be
II: PRE-INSTALLATION
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 oor is not
level, or if water may be encountered on oor
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 ooring. DO NOT operate on
masonry oors, 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.
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: 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: AP-U™ 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

8
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 oor, then, remove the skid.
3. Position boiler for nal 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
ammable 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(ft3) = 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 unconned space. If the
result is less than 50 ft3/1000 BTU per hour then the
space is considered a conned space.
4. For boiler located in an unconned space of a
conventionally constructed building, the fresh air
inltration through cracks around windows and
doors normally provides adequate air for
combustion and ventilation.
5. For boiler located in a conned space or an
unconned 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
conned space. Use indoor air if two permanent
openings communicate directly with additional
space(s) of sufcient volume such that combined
volume of all spaces meet criteria for unconned
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 xed in the open
position, or interlocked with the equipment to
open automatically during equipment operation.
II: PRE-INSTALLATION (continued)

9
INSTALLATION INSTRUCTIONS FOR OPTIONAL SHIELD REQUIRED
FOR COMBUSTIBLE FLOOR
This shield for combustible oors is intended for use only with the following New Yorker oil-red boilers:
Use Part Number 6183504 for the following models:
AP-490U AP-590U AP-690U AP-790U
ADDS 4-3/16” TO BOILER HEIGHT
1) Place shield on combustible oor 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 3. These dimensions will
assure that the boiler jacket will be at least 18” from
the side and rear walls and 48” from the front wall, as
required by ANSI/NFPA 31.
3) Fasten shield to combustible oor 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 at on top surface of shield and does not
over-hang shield on any side. Conrm clearance to
combustible walls. Refer to Figure 2.
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 for
each of those three sides.
Figure 3: Floor Shield
II: PRE-INSTALLATION (continued)

10
Figure 4: Recommended Piping for Combination
Heating and Cooling (Refrigeration) System
III: WATER PIPING AND TRIM
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 ttings.
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 ttings 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 6A and 6B. 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.
New Yorker recommends sizing the system
circulator to supply sufcient ow (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 4. 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 ow 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.
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
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. New Yorker’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.

11
line as illustrated in Figures 6A and 6B in order
to regulate water ow 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 5,
6A and 6B. 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
oor 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 lled. 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 5, 6A and 6B.
D. INSTALL DRAIN VALVE in return piping. See
Figures 6A and 6B.
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 ushed. A qualied water
treatment chemical specialist should be consulted for
recommendations regarding appropriate chemical
compounds and concentrations which are compatible
with local environmental regulations.
Figure 5: Air Vent and Safety Relief Valve
Installation Detail
F. AFTER THE BOILER AND SYSTEM HAVE BEEN
CLEANED and ushed, and before relling 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 7. See Table 3 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 xtures. Adjust and
maintain the mixing valve in accordance with the
manufacturer's instructions. DO NOT operate
tankless heater without mixing valve.
III: WATER PIPING AND TRIM (continued)

12
Figure 6A: Recommended Boiler Piping for Circulator Zoned Heating Systems, Supply Side Circulator
III: WATER PIPING AND TRIM (continued)

13
Figure 6B: Boiler Piping for Zone Valve Zoned Heating Systems, Supply Side Circulator
III: WATER PIPING AND TRIM (continued)

14
Figure 7: Schematic Tankless Heater Piping
TABLE 3: TANKLESS HEATER RATINGS
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 7.
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 benecial to the
tankless heater but to piping and xtures plus the
many other benets derived from soft water.
THE FOLLOWING GUIDELINES SHOULD BE
FOLLOWED WHEN PIPING THE TANKLESS HEATER:
1. FLOW REGULATION — If ow 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 ow regulator matching the heater
rating should be installed in the cold water line to
the heater. The ow 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 ow
regulator also limits the ow 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 xtures. 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 dishwashers and automatic washers is
Boiler Model
Tankless Heater Model
S-5A
GPM PSID
AP-490U 3½ 15
AP-590U
3¾ 25AP-690U
AP-790U
III: WATER PIPING AND TRIM (continued)

15
IV: VENTING
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 re
ofcials about restrictions and installation inspection
in your area.
2. The AP-U Series is designed to be vented into a
reclay 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 sufcient 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 9 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
efciency 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 red or an inefcient oil red boiler
built into a home without insulation or storm
windows. With increasing fuel prices that home
probably has been insulated and tted 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 efciency
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 ring rate, reduced ring 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 red 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 ring 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
ue 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.

16
Figure 8: Recommended Smokepipe Arrangement and Chimney Requirements
Figure 9: Draft Regulator Locations
IV: VENTING (continued)

17
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 10 and/or 11.
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 10 or 11 for
the electrical diagram for this type of system.
Connect the system circulator wire leads to the
proper locations on the Aquastat control, L7224/
L7248. See Figure 10 or 11.
C. INSTALL A ROOM THERMOSTAT on an
inside wall about four feet above oor. Never install
thermostat on an outside wall or where it will be
inuenced by drafts, hot or cold water pipes, lighting
xtures, television, rays of the sun or near a replace.
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
L7224 or L7248 control.
Heat Anticipator in Thermostat should be set to .1 amps.
If system tends to overheat above the thermostat’s
temperature setting, reduce heat anticipator setting by
.1 or .2 amps. If system tends to short cycle without
reaching desired room temperature, increase heat
anticipator setting by .1 or .2 amps.
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.
V: ELECTRICAL
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.

18
V: ELECTRICAL (continued)
Figure 10: Schematic Wiring Diagram, without Tankless Heater, Cold Start Control (Beckett and Riello Burners)
REFER TO FIGURE 12 FOR SCHEMATIC WIRING DIAGRAM OF APPROPRIATE BURNER AND OIL PRIMARY CONTROL OPTION

19
V: ELECTRICAL (continued)
Figure 11: Schematic Wiring Diagram, with Tankless Heater, Warm Start Control (Beckett and Riello Burners)
REFER TO FIGURE 12 FOR SCHEMATIC WIRING DIAGRAM OF APPROPRIATE BURNER AND OIL PRIMARY CONTROL OPTION

20
V: ELECTRICAL (continued)
Figure 12: Schematic Wiring Diagrams For All Burner Options w/Various Oil Primary Controls
NOTE: APPLY THIS BURNER
SCHEMATIC TO APPROPRIATE
STEAM OR WATER BOILER
CONTROL SCHEMATIC, REFER TO
FIGURES 10 AND 11
NOTE: APPLY THIS BURNER
SCHEMATIC TO APPROPRIATE
STEAM OR WATER BOILER
CONTROL SCHEMATIC, REFER TO
FIGURES 10 AND 11