A.O. Smith Burkay HW-300 User manual

GAS FIRED COMMERCIAL COPPER BOILERS
User's Manual
PRINTED IN THE U.S.A. 0212 321082-000
Thank you for buying this energy efcient boiler.
We appreciate your condence in our products.
MODELS: HW
300, 399, 420, 520, 670
FOR HYDRONIC HEATING AND
HOT WATER SUPPLY
UP - FLOW MODELS
OPERATION - MAINTENANCE -
LIMITED WARRANTY
25589, Highway 1
McBee, SC 29101
WARNING: If the information in these
instructions is not followed exactly, a fire
or explosion may result causing property
damage, personal injury or death.
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS:
Do not try to light any appliance.
Do not touch any electrical switch; do
not use any phone in your building.
Immediately call your gas supplier
from a 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.
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•
•
•
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2
TABLE OF CONTENTS
TABLE OF CONTENTS.......................................................................... 2
SAFE INSTALLATION, USE AND SERVICE.......................................... 3
GENERAL SAFETY................................................................................ 4
INTRODUCTION.................................................................................... 5
Abbreviations used ............................................................................ 5
Qualications ..................................................................................... 5
CONTROL COMPONENTS ................................................................... 6
BOILER START UP AND OPERATIONS ............................................. 10
Filling the system............................................................................. 10
Precautions...................................................................................... 10
Pilot and main burner ...................................................................... 10
Checking and adjusting input .......................................................... 12
TROUBLESHOOTING ......................................................................... 16
MAINTENANCE PROCEDURES......................................................... 24
Manual reset high limit switch continuity test................................... 24
Pressure relief valve test ................................................................. 24
Cleaning and ushing instructions................................................... 24
Venting maintenance ....................................................................... 25
NOTES ................................................................................................. 26
LIMITED WARRANTY.......................................................................... 27

3
The proper installation, use and servicing of this boiler is extremely important to your safety and the safety of others.
Many safety-related messages and instructions have been provided in this manual and on your boiler to warn you and others of
a potential injury hazard. Read and obey all safety messages and instructions throughout this manual. It is very important that the
meaning of each safety message is understood by you and others who install, use, or service this boiler.
DANGER indicates an imminently
hazardous situation which, if not avoided,
will result in injury or death.
This is the safety alert symbol. It is used to alert you to
potential personal injury hazards. Obey all safety
messages that follow this symbol to avoid possible
injury or death.
WARNING indicates a potentially hazardous
situation which, if not avoided, could result
in injury or death.
CAUTION indicates a potentially hazardous
situation which, if not avoided, could result in
minor or moderate injury.
CAUTION used without the safety alert
symbol indicates a potentially hazardous
situation which, if not avoided, could result in
property damage.
WARNING
CAUTION
CAUTION
DANGER
All safety messages will generally tell you about the type of hazard, what can happen if you do not follow the safety message, and
how to avoid the risk of injury.
The California Safe Drinking Water and Toxic Enforcement Act requires the Governor of California to publish a list of substances
known to the State of California to cause cancer, birth defects, or other reproductive harm, and requires businesses to warn of
potential exposure to such substances.
This product contains a chemical known to the State of California to cause cancer, birth defects, or other reproductive harm. This
boiler can cause low level exposure to some of the substances listed in the Act.
IMPORTANT DEFINITIONS
Gas Supplier: The Natural Gas or Propane Utility or service who supplies gas for utilization by the gas burning appliances within
this application. The gas supplier typically has responsibility for the inspection and code approval of gas piping up to and including
the Natural Gas meter or Propane storage tank of a building. Many gas suppliers also offer service and inspection of appliances
within the building.
SAFE INSTALLATION, USE AND SERVICE
APPROVALS
H

4
GENERAL SAFETY

5
This design complies with the current edition of the ANSI Z21.13
low-pressure boiler standard.
Compliance under this standard implies that when the boiler
underwent test, the gas manifold and control assembly pro vided
on the boiler met safe lighting and other performance criteria.
Detailed installation diagrams are found in this manual. These
diagrams will serve to provide the installer a reference for the
materials and methods of piping necessary. It is essential that
all water, gas piping and wiring be installed as shown on the
diagrams. You should thoroughly read and understand this
manual before installation and/or operation of this boiler.
The factory warranty will be void if the boiler(s) have been
improperly installed or operated.
In addition to these instructions, the boiler(s) shall be installed
in accordance with those installation regulations in force in the
local area where the installation is to be made. These shall be
carefully followed in all cases. Authorities having jurisdiction
should be consulted before installations are made.
In the absence of local codes, the installation must comply with
the current editions, as follows:
In the United States:
The National Fuel Gas Code, ANSI Z223.1/NFPA 54 and the
National Electric Code, NFPA 70.
In Canada:
Installation Code CAN/CSA B149.1 and Canadian Electrical
Code, CSA C22.1.
ABBREVIATIONS USED
Abbreviations found in this Instruction Manual include :
• ANSI - American National Standards Institute
• ASME - American Society of Mechanical Engineers
• NEC - National Electrical Code
• NFPA - National Fire Protection Association
• UL - Underwriters Laboratory
• CSA - Canadian Standards Association
INTRODUCTION
QUALIFICATIONS
QUALIFIED INSTALLER OR SERVICE AGENCY
Installation and service of this boiler requires ability equivalent
to that of a Qualied Agency, as dened by ANSI below. In the
eld involved. Installation skills such as plumbing, air supply,
venting, gas supply and electrical supply are required in addition
to electrical testing skills when performing service.
ANSI Z21.13 - CSA 4.9: “Qualied Agency” - “Any individual,
rm, corporation or company that either in person or through
a representative is engaged in and is responsible for (a) the
installation, testing or replacement of gas piping or (b) the
connection, installation, testing, repair or servicing of appliances
and equipment; that is experienced in such work; that is familiar
with all precautions required; and that has complied with all the
requirements of the authority having jurisdiction.”
If you are not qualied (as dened by ANSI above) and licensed
or certied as required by the authority having jurisdiction
to perform a given task do not attempt to perform any of the
procedures described in this manual. If you do not understand
the instructions given in this manual do not attempt to perform
any procedures outlined in this manual.

6
FIGURE 1. COMPONENT LOCATIONS
CONTROL COMPONENTS

7
THERMAL BALANCER
Figure 4 shows the internal wiring of the thermal balancer. The
device may be tested after disconnecting the four leads from
their respective terminals on the unit.
1. Apply a test light to the yellow and red leads.
• The lamp should light as the contact in this circuit is
normally closed when the resistor is cool.
2. Apply a light to the black and yellow leads.
• The lamp should not light as the contact in this circuit is
normally open when the resistor is cool.
3. Remove the test light.
4. Apply 120 volts to the white and red leads which power the
1900 ohm resistor. After a warming period the contacts of
the thermal balancer should operate.
5. Remove the test light.
6. Apply the test light as described in steps 1 and 2.
While the resistor is still warm the lamp indications should be the
opposite as described previously.
MANUAL RESET HIGH LIMIT
This boiler is equipped with a manual reset high limit switch,
located under the small cover on the side of the jacket, see
Figure 5. This device provides positive shutdown of the boiler
in the event of boiler or system malfunction. Should the surface
temperature of the copper tubing heat exchanger reach 250°F
(120°C), the high limit switch will activate, the gas control valve
will close, the pilot and main burners will be extinguished. If
the high limit switch should shut off unit, check the following
conditions:
• No water in boiler.
• Restricted water ow through the boiler.
• Improper wiring (boiler ring without circulating pump
operating).
• Pump failure.
After correcting failure condition remove the protector switch
cover and push the reset button. The high limit switch may be
reset after the coil surface cools to 6°F (3.3°C) below the trip
setting.
AUTO RESET HIGH LIMIT
The high limit is a safety device wired in series with the ignition
system. Set the high limit control to approximately 100°F above
the maximum designed system temperature. If the boiler outlet
water temperature should exceed the high limit setting, the main
gas control valve will close but the circulating pump will continue
to operate. Maximum adjustable setting is 115°C (239°F) cut-out
with a 30°C (86°F) to 250°C (482°F) adjustable differential, see
Figure 2.
INTERMITTENT IGNITION CONTROL MODULE
The Honeywell S-8600 control module contains the electronic
components of the system and also serves as a control wiring
system for the controls mounted on the boiler. The control
module performs the following functions:
1. Checks for safe-start by sensing for a false ame condition
on start-up.
2. Generates a potential of 15,000 volts for spark ignition of the
pilot burner.
3. Opens the pilot valve.
4. Discontinues ignition spark when the pilot flame is
established. The S-8600 control used on propane
gas models provides safety lockout if the pilot
fails to ignite within the pilot flame establishing
period. The S-8600 control used on natural gas
models continues trial for ignition until pilot flame
is established.
5. After proof of pilot ame, opens then main valve.
6. On a power loss, shuts the boiler down. When power is
restored it will begin a new ignition cycle.
7. On a loss of ame, shuts off main gas and starts trial for pilot
ignition.
Please refer to Troubleshooting section for more information.
FIGURE 2. AUTO RESET HIGH LIMIT
FIGURE 3. S-8600 INTERMITTENT IGNITION CONTROL
MODULE (IID)
FIGURE 4. THERMAL BALANCER
FIGURE 5. HIGH LIMIT SWITCH

8
PRESSURE RELIEF VALVE
An ASME rated pressure relief valve is furnished with the boiler.
A tting for the pressure relief valve is provided in the top of the
boiler. Never operate the heating elements without being certain
the boiler is lled with water and a properly sized pressure relief
valve is installed in the pressure relief valve opening provided.
The pressure rating of the pressure relief valve should be equal
to or less than the rated pressure capacity of any component
in the system including the boiler. Should the valve need to be
replaced, call the toll free phone number listed on the back of this
manual for further technical assistance.
A discharge pipe from the pressure relief valve should terminate
at an adequate oor drain. Do not thread, plug, or cap the end of
the drain line.
The Discharge Pipe:
• Shall not be smaller in size than the outlet pipe size of the
valve, or have any reducing couplings or other restrictions.
• Shall not be plugged or blocked.
• Shall not be exposed to freezing temperatures.
• Shall be of material listed for hot water distribution.
• Shall be installed so as to allow complete drainage of both
the pressure relief valve and the discharge pipe.
• Must terminate a maximum of six inches above a oor
drain or external to the building. In cold climates, it is
recommended that the discharge pipe be terminated at an
adequate drain inside the building.
• Shall not have any valve or other obstruction between the
pressure relief valve and the drain.
Once the boiler is installed and lled with water and the system
is pressurized, manually test the operation of the pressure relief
valve.
Explosion Hazard
Pressure Relief Valve must
comply with ASME code.
Properly sized Pressure Relief
Valve must be installed in
opening provided.
Can result in overheating and
excessive tank pressure.
Can cause serious injury or death.
Water Damage Hazard
Pressure Relief Valve discharge pipe must
terminate at adequate drain.
•
CAUTION
If any pressure relief valve is replaced, the replacement valve
must comply with the current editions of the ASME Boiler and
Pressure Vessel Code, Section IV or CSA B51, as applicable.
Select a pressure relief valve with a discharge NOT less than the
boiler input, and a pressure rating NOT exceeding the working
pressure of any component in the system.
A. O. Smith supplies a 125 psi pressure relief valve for hot water
supply systems and 50 psi pressure relief valve for space heating
application.
An ASME rated temperature and pressure relief valve must be
installed on each and every water storage tank in a hot water
supply system.
The storage tank temperature and pressure (T & P) relief valve
must comply with the applicable construction provisions of the
Standard for Relief valves and Automatic Gas Shutoff Devices
for Hot Water Supply Systems, Z21.22 - CSA 4.4. The T & P
valve must be of the automatic reset type and not embody a
single-use type of fusible plug, cartridge or linkage.
The T & P relief valve should have a maximum temperature
rating of 100°C (210°F), a pressure rating NOT exceeding the
lowest rated working pressure of any system component, and a
discharge capacity exceeding the total input of the water boilers
supplying water to the storage tank.
Locate the T & P relief valve (a) in the top of the storage tank
or (b) in the side of the tank on centerline within upper 6 inches
from the top of the tank. Refer to the Piping Diagrams section
in Instruction Manual. Tapping shall be threaded in accordance
with the latest version of the Standard for Pipe Threads, General
Purpose (inch), ANSI/ASME B.120.1.

9
Use anti-scald valve(s) in the hot water system to reduce the
risks of scalds at points of use such as lavatories, sinks and
bathing facilities.
A change in water temperature in the storage tank lower than the
Tank Temperature Control setting will cause the sensor to close
its contacts and consequently energize the boiler.
If the Tank Temperature Control is out of calibration, replace it
with a new one; do not attempt to x this control.
THERMOMETERS
Thermometers should be obtained and eld installed as shown
in the installation diagrams.
Thermometers are installed in the system as a means of
detecting a possible liming condition in the boiler. An increase
of 5°F (3°C) over the normal temperature rise through the boiler
is an indication that lime is present. The term "temperature"
designates the difference between the boiler inlet and outlet
water temperature.
An increase of 5°F (3°C) above the recorded temperature
rise may signify a liming condition in the coils or heat
exchanger. Refer to Cleaning and Flushing Instructions on Page
24 for deliming instructions.
Record temperature rise at initial start-up for future reference.
DRAIN VALVE (NOT SUPPLIED)
A drain valve must be obtained and installed on each boiler and
tank for draining purposes.
TANK TEMPERATURE CONTROL
The water temperature in the storage tank is controlled by the
Tank Temperature Control. The sensing element is mounted
inside the hot water storage tank.
The tank temperature control is adjustable from 100°F (37.7°C)
to 220°F (104.4°C). It is recommended that lower water
temperatures be used to avoid the risk of scalding. It is further
recommended, in all cases, that the water temperature be set
for the lowest temperature which satises the user’s hot water
needs. This will also provide the most energy efcient operation
of the boiler and minimize scale formation.
The boiler should be located in an area where the general public
does not have access to set temperatures. Setting the water
temperature at 120°F (49°C) will reduce the risk of scalds.
Some people are more likely to be permanently injured by
hot water than others. These include the elderly, children, the
inrm and the physically/mentally disabled. Table 1 shows the
approximate time-to-burn relationship for normal adult skin. If
anyone using hot water provided by the boiler being installed ts
into one of these groups or if there is a local code or state law
requiring a certain water temperature at the point of use, then
special precautions must be taken. Contact a qualied service
technician or qualied agency.
Water Temperature Time to Produce 2nd & 3rd
Degree Burns on Adult Skin
180°F (82°C) Nearly instantaneous
170°F (77°C) Nearly instantaneous
160°F (71°C) About 1/2 second
150°F (66°C) About 1-1/2 seconds
140°F (60°C) Less than 5 seconds
130°F (54°C) About 30 seconds
120°F (49°C) More than 5 minutes
Water temperature over 125°F (52°C)
can cause severe burns instantly
resulting in severe injury or death.
Children, the elderly and the
physically or mentally disabled are at
highest risk for scald injury.
Feel water before bathing or
showering.
Temperature limiting devices such as
mixing valves must be installed
when required by codes and to
ensure safe temperatures at fixtures.
TABLE 1. TEMPERATURE AND TIME TO PRODUCE BURNS

10
BOILER START UP AND OPERATIONS
After placing the boiler into operation, the ignition system safety
shutoff device must be tested by the following test method.
1. Reset High Limit Temperature Control to lowest setting.
(See Figure 2 on Page 7).
2. Reset System Controller to maximum setting, causing a call
for heat and allowing unit to run until High Limit Temperature
Control trips.
3. Resetting the High Limit Temperature Control to a higher
setting, unit should run.
4. Reset System Controller and High Limit Temperature
Control to desired temperature. If unit fails to run, refer to
Troubleshooting section in this manual on Page 16.
Before operating the boiler, the entire system must be lled with
water, purged of air and checked for leaks. Do not use Stop Leak
or other boiler compounds. The gas piping should also be leak
tested.
Any safety devices including low water cutoffs used in conjunction
with this boiler should receive periodic (every six months)
inspection to assure proper operation. A low water cutoff device
of the oat type should be ushed every six months. All pressure
relief valves should be inspected and manually operated at least
twice a year.
IMPORTANT
It is recommended that a qualied service technician perform
the initial ring of the boiler. At this time the user should not
hesitate to ask the individual any questions which he may
have in regard to the operation and maintenance of the unit.
FILLING THE SYSTEM
1. Fast ll system through bypass until pressure approaches
desired system pressure. Close bypass valve and permit
pressure to be established by the pressure reducing valve.
2. Vent all high points in system to purge system of air.
If pressure bleeding of system is desired, install valves as shown
in the Piping Diagrams of the Instruction Manual.
Where cast iron radiation and motorized valves are used,
conventional system pressure and installation practices should
be followed.
Provisions should be made to permit manual venting of radiators
or convectors.
PRECAUTIONS
If the unit is exposed to the following, do not operate boiler
until all corrective steps have been made by a qualied service
technician:
• Flooding to level of burner or controls or higher.
• Exposure to re.
• If damaged.
• Firing without water.
• Sooting.
PILOT AND MAIN BURNER
To maintain safe operation of the boiler, check the pilot and
the main burner once every six months for proper ame
characteristics.
1. MAIN BURNER
The main burner, Figure 6, should display the following
characteristics:
• Provide complete combustion of gas.
• Cause rapid ignition and carryover of ame across entire
burner.
• Give reasonably quiet operation during ignition, burning
and extinction.
• Cause no excessive lifting of ame from burner ports.
If the proceeding burner characteristics are not evident, check
for accumulation of lint or other foreign material that restricts or
blocks the air openings to the burner or boiler.
Also check for good ow of combustion and ventilating air to the
unit. Maintain a clear area around the boiler at all times.
The boiler should be periodically inspected by a qualied servicer
for continuous safe operation.
Qualied servicers should follow this procedure when the boiler’s
burners need cleaning.
a. Turn off the electrical power and close the main manual gas
shutoff valve. Refer to Lighting & Operating Instructions on
Pages 14 and 15.
• Allow boiler parts to cool before disassembly.
b. Remove main burner manifold assembly from boiler.
• Refer to parts list supplied with this manual for
disassembly aid.
c. Remove any loose foreign material such as dust or lint with
a vacuum. Check all ports, orices, and air openings for
blockage. Dislodge any foreign material causing blockage.
Remove any soot or carbon deposits with a rag making sure
to remove any lint left on burner by vacuuming again.
d. Reinstall the burner manifold assembly on boiler.
e. Restore electrical power and gas supply to boiler.
• Put the boiler back in operation by following the lighting
instructions in this manual or on the lighting and
operating label on the boiler. Refer to Pages 14 and 15.
• Check for gas leaks and proper boiler and vent operation.
FIGURE 6. MAIN BURNER

11
FIGURE 7. SPARK IGNITION PILOT BURNER AND BURNER FLAME
FIGURE 8. ADJUSTING PILOT FLAME
2. PILOT BURNER - ELECTRONIC IGNITION
To establish pilot ame without main burner operation, it will be
necessary to perform the following steps:
Servicing of the pilot burner (every six months) includes
keeping pilot shield (not shown) free of lint, cleaning the burner
head, the primary air opening and the orice of the pilot burner,
Figure 7.
a. Open fused disconnect switch or shut off electrical power to
the boiler.
b. Disconnect wire from MV wire on valve.
c. Close fused disconnect switch to restore electrical power to
the boiler.
The pilot will now ignite provided the system is calling for heat.
d. Adjust pilot ame.
To adjust the pilot ame, remove the cap screw from the pilot
adjusting screw (Figure 8) and turn to deliver a sufcient ame at
the pilot burner to cover 3/8" to 1/2" (10-12 mm) of the sensing
probe tip. See Figure 7.
Check for good terminal connection at the sensing probe at the
pilot burner assembly if pilot does not light.
Check for electrical power to the valve. If electrical power and
gas are present at the valve and the pilot does not operate when
system calls for heat, replace valve.
e. Low gas pressure
• Adjust pilot ame by means of the pilot gas adjustment
located in the gas control valve.
• The pilot ame should envelop 3/8 to 1/2 inch (10-12 mm)
of the tip of the thermocouple. Remove pilot adjustment
cover screw, Figure 8. Turn inner adjustment screw or pilot
adjusting valve clockwise to decrease, or counterclockwise
to increase pilot ame. Be sure to replace cover screw on
combination gas control valve after adjustment to prevent
possible gas leakage.
f. Clogged pilot burner orice.
• Clean or replace orice. A clogged orice will restrict gas
ow and result in low thermocouple output.
g. Incorrect orice.
• Replace. The Orice size is stamped on the wrench ats.
h. Clogged primary air opening.
• Restricted air passages will soften the pilot ame and
result in poor thermocouple ame impingement.

12
5. Repeat steps 1 thru 6 of the OPERATING INSTRUCTIONS.
6. Remove the pressure gauge or manometer from the
manifold pressure tapping. Replace the screw-in plug in the
manifold pressure tap.
7. Repeat steps 7 thru 11 of the OPERATING INSTRUCTIONS
on Page 15. The boiler will resume normal operation.
When the boiler is operating at full capacity, or full gas input,
it should consume 1 cu.ft. of gas in approximately the time
indicated in Table 2.
TYPE
GAS
HEATING
VALUE
BTU/FT.
TIME TO CONSUME 1 CU. FT. OF GAS
(SECONDS)
HW-300 HW-399 HW-420 HW-520 HW-670
Natural 1050 12.6 9.5 9.0 7.3 5.7
Propane 2500 30.0 22.6 21.4 17.3 13.4
Minor variances from input on rating plate can be corrected by
adjustment of gas pressure regulators.
The inlet gas pressure must not exceed or be less than the
values shown on rating plate.
CHECKING AND ADJUSTING INPUT
1. Follow steps 1 thru 6 of the OPERATING INSTRUCTIONS
on Page 15.
2. Attach a pressure gauge or a manometer to the manifold
pressure tapping and refer to Table 2 for correct manifold
pressure.
3. Follow steps 7 thru 11 of the OPERATING INSTRUCTIONS.
4. Use this formula to “clock” the meter. Be sure that other gas
consuming appliances are not ON during this interval.
3600 x H = Btuh
T
Btuh = The approximate actual input rate.
T = Time in seconds to burn one cubic foot of gas.
H = Heating value of the fuel gas in Btu per cubic foot of gas.
EXAMPLE:
T = 9.0 seconds/ft3
H = 1050 Btu/ft3(natural gas)
Btuh = ?
Gas ow through meter:
3600 x 1050 = 420,000 Btuh
9.0
Small changes in the input rate may be made by adjusting the
manifold pressure, refer to Gas Manifold Pressure Regulators
in the Instruction Manual. Under no circumstances should you
exceed the maximum input rate for the boiler. Refer to Recovery
Capacities Table in the Instruction Manual.
TABLE 2. CONSUMPTION RATE (REFER TO OPERATING
AT FULL INPUT OR FULL CAPACITY)
Breathing Hazard - Carbon Monoxide Gas
Breathing carbon monoxide can cause brain damage or
death. Always read and understand instruction manual.
Under no circumstances should
the input exceed the rate shown
on the boiler’s rating label.
Overfiring could result in damage to
the boiler’s and sooting.
Gas and carbon monoxide detectors
are available.
Fire and Explosion Hazard
Gas and carbon monoxide detectors are
available.
Overfiring could result in fire or
explosion.
Under no circumstances should the
input exceed the rate shown on the
boiler’s rating label.

13
START
STAGE 1
TRIAL FOR
IGNITION
STAGE 2
MAIN BURNER
OPERATION
END
THERMOSTAT (CONTROLLER) CALLS FOR HEAT
SPARK GENERATOR POWERED
First valve (pilot) operator opens
PILOT BURNER OPERATION
Pilot burner lights. Pilot burner does not light
Module senses Module Response
ame current. S-8600M After 15 sec. ignition
shut-down. 5 minute
time delay before re-try.
S-8600H After 15 sec. ignition
system locks out
must be manually reset.
FLAME CURRENT SENSED
• Spark generator off.
• Second valve operator (main) opens.
MAIN BURNER OPERATION
Module monitors pilot ame current.
THERMOSTAT (CONTROLLER) SATISFIED
Valves close, pilot and main burners are off.
POWER INTERRUPTION
System shuts off, restarts
when power is restored.
PILOT FLAME FAILURE
Main valve closes.
Module starts trial for
ignition.

14
LIGHTING AND OPERATING INSTRUCTIONS (NATURAL AND PROPANE FOR HW300 - HW399

15
LIGHTING AND OPERATING INSTRUCTIONS (NATURAL AND PROPANE WITH I.I.D. FOR HW420 & UP)

16
TABLE 3. CER-TEMP 80 RECOVERY SYSTEM CHECKOUT PROCEDURE
Before any extensive troubleshooting, perform the following:
Ensure that:
• Voltage (120 vac) is supplied to the boiler.
• System control (tank temperature control, thermostat,
etc.) is calling for boiler operation (call for heat).
• Other contacts (switches) are closed (relay, low water
cutoff, ow switch, coil protector, pressure switch, etc.).
• Gas supply pressure is within the maximum and minimum
operating ranges listed on the boiler rating plate/label.
• Voltage (24 vac) is supplied by transformer.
• Boiler is wired according to wiring diagram.
Note: Cross wiring the 24 volt circuit of the relay will short the
transformer.
• All wire terminals/connectors are rmly attached to
valves, modules, switches, limit controls, etc.
• For Propane (LP) models only check for possible lockout
condition of the ignition module.
Use this checkout for Cer-Temp 80 Recovery Systems. (For hot water supply application only)
CHECKOUT SEQUENCE SYSTEM OPERATION CAUSE REMEDY
CORRECT INCORRECT
Set tank temperature
control (thermostat)
20°F (10°C) below tank
water temperature.
Circulating pump and
burner shut off.
With thermal balancer,
pump off delay of
approximately 2 minutes.
Pump and burner remain
on.
Tank temperature control
(thermostat) defective. Replace.
System wiring is
incorrect. Correct wiring.
Circulating pump on. Pump wired for
continuous operation. Correct wiring.
Burner on.
Gas control valve stuck
or defective.
Correct or replace
valve.
System wiring is
incorrect. Correct wiring.
Set tank temperature
control (thermostat)
20°F (10°C) above tank
water temperature.
Circulating pump and
burner on.
Circulating pump on.
High limit control set too
low.
Replace. (If
problem proven to
be at this control by
applying jumper to
terminals.)
High limit control
differential too wide.
System wiring is
incorrect. Correct wiring.
Coil protector switch has
activated.
Remove control
cover, depress
reset button.
Gas control valve or
wiring defective.
Check wiring.
Repair or replace
valve.
Circulating pump and
burner off.
Power off or system
wiring is incorrect.
Check power supply
and wiring.
Tank temperature control
(thermostat) defective. Replace.
Burner on. System wiring is
incorrect. Correct wiring.
Boiler outlet
temperature exceeds
210°F (100°C).
Circulating pump on. Circulating pump and
burner on.
High limit control
defective, or set too high
(max. should be set at
200°F).
Replace.
Set tank temperature
control (thermostat)
for desired water
temperature.
System maintains desired
water temperature.
TROUBLESHOOTING

17
CHECKING HONEYWELL S-8600H OR S-8600M
INTERMITTENT IGNITION CONTROLS
Turn off gas supply.
Is voltage (24 Vac) across the 24 V terminals
on module during “Call for heat”?
Turn off power supply.
Is ignition cable rmly plugged into pilot
assembly and module?
Is ground wire rmly attached to pilot assembly and GND terminal
on module?
Ensure ground strap is the closest metal to the igniter/sensor
rod (electrode) to prevent the spark from shorting out to other metal
parts (pilot screen, pilot shield, etc.).
Ignition cable must not touch metal surfaces or current
carrying wires.
Is there a 1/8” gap between ground strap and electrode?
Is the ceramic insulator surrounding the electrode cracked or broken?
Replace pilot burner assembly.
Replace ignition module.
Turn on gas supply.
Turn on power supply.
Securely connect cable
and/or ground wire.
Carefully bend downward
top of ground strap
to achieve 1/8”
spark gap.
Replace Ignition
Module.
YES
NO
YES
YES
NO
NO
NO
Is voltage (24 Vac) across the PV & MV/PV terminals on
“call for heat”?
YES
NO
NOTE: S-8600M will automatically reset every 5 minutes. S8600H pilot
valve will be de-energized if module goes into lockout condition. Reset
system by turning electrical power off or by turning system controller to
off or down below "call for heat". Wait one minute, then turn system on.
YES
Are ignition cable and ground wire in good condition
(not brittle, burnt or cracked)?
Replace pilot burner
and/or ground wire.
YES
NO
NO SPARK AT PILOT BURNER
YES

18
CHECKING HONEYWELL S-8600H OR S-8600M
INTERMITTENT IGNITION CONTROLS
SPARK AT PILOT BURNER BUT PILOT WILL NOT LIGHT
Ensure all manual shutoff valves are fully open; all lters are
clean; all gas connections are gas tight; pilot tubing is not damaged,
obstructed or kinked; and pilot orice is unclogged. Check for air in gas
line, purge (bleed) line if necessary.
Are the wires securely attached to the pilot operator on the gas control
and to the PV & MV/PV terminals on the ignition module?
Install a pressure gauge in the pilot tubing line between the gas control
and the pilot burner assembly. Ensure that the pilot adjustment screw
(under cap) is adjusted to a position that will permit gas to ow.
Is pilot gas owing during ignition attempt?
Turn off power supply.
Is ignition cable rmly plugged into pilot assembly and module?
Is ground wire rmly attached to pilot assembly and GND terminal on
module?
Are ignition cable and ground wire in good condition (not brittle, burnt, or cracked)?
Ensure ground strap is the closest metal to the igniter/sensor
rod (electrode) to prevent the spark from shorting out to
other metal parts (pilot screen, pilot shield, etc.).
Ignition cable must not touch metal surfaces or current
carrying wires.
Is there a 1/8” gap between ground strap and electrode?
Is ceramic insulator surrounding the electrode in good
condition (not cracked or broken)?
Is there excessive draft conditions that may cause pilot
burner ignition problems?
Correct draft problems in a manner that would ensure
adequate combustion and ventilation air and proper
pilot burner performance.
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
Attach wires rmly.
Replace gas control valve.
Turn on power supply.
Securely connect
cable and/or ground
wire.
Replace pilot burner
and/or ground wire.
Carefully bend down-
wards top of ground
strap to achieve
1/8” spark gap.
Replace pilot burner.
Replace ignition
module.
YES
YES

19
CHECKING HONEYWELL S-8600H OR S-8600M
INTERMITTENT IGNITION CONTROLS
PILOT BURNER LIGHTS BUT MAIN BURNER DOES NOT LIGHT
Does the pilot ame cover 3/8” to 1/2”
of igniter/sensor rod?
Does spark stay on for more than
15 seconds after the pilot is “proven” (lit)?
Ensure the ground wire and ignition cable are
separate from each other (prevents shorting
out).
Are they in good condition (not brittle, burnt or
cracked)?
Is the ceramic insulator surrounding the
igniter/sensor rod in good condition
(not broken or cracked)?
Is the igniter/sensor rod in good
condition (not worn, corroded, sooted
or damaged)?
Replace ignition module.
Correct the situation by consulting the
installation or user’s manual on how to
adjust pilot ame.
Is voltage (24 Vac) across terminals
MV & MV/PV?
Are the wires securely attached to the main
valve operator on the gas control and to
terminals MV & MV/PV on ignition module?
Replace
ignition
module.
Replace main gas control valve.
Replace pilot burner
and/or ground wire.
Replace pilot burner.
Clean rod or replace
pilot burner if necessary.
Attach
wires
rmly.
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
YES
YES

20
CHECKING HONEYWELL S8600H OR S-8600M
INTERMITTENT IGNITION CONTROLS
NO SPARK AT PILOT BURNER BUT PILOT WILL NOT LIGHT
Turn off gas supply.
Is there a good connection between terminals?
Is module securely attached to boiler for good ground
connection?
Is voltage (24VAC) across transformer positive terminal and
GND with "call for heat"?
Is voltage (24VAC) across ignition module terminals 24 Volt and GND on
"call for heater"?
NOTE: (For Propane (LP) models only) Pilot Valve will be de-energized
if module goes into lockout condition. Reset system by turning electrical
power off or by turning system controller down below "call for heat". Wait
one minute then turn system on.
Turn on gas supply and/or
power supply.
Turn off power supply.
Is high voltage cable assembly rmly plugged into module?
Is pilot ground wire rmly attached to the pilot assembly and GND
terminal on module?
Are high voltage cable and ground wire in good condition (not brittle,
burnt or cracked)?
Make sure pilot ame spreader (hood) is the closest metal to
the electrode to prevent the spark from shorting out to other metal parts
(pilot screen, pilot shield, etc).
High voltage cable must not touch metal surfaces or current carrying
wires.
Is there a 7/64" spark gap between the tip (edge) of the hood and
electrode, and is the gap located in the pilot gas stream?
Is the ceramic insulator surrounding the electrode in good
condition (not cracked or broken)?
Replace pilot burner assembly.
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
Check the circuit providing
24 VAC.
Replace ignition module.
Securely connect cable
and/or ground wire.
Replace pilot burner and/
or ground wire.
Carefully bend down-
wards top of ground
strap to achieve
1/8” spark gap.
Replace ignition module.
NO
Fix connection and/or
tighten module to the
boiler.
YES
NO