SERVICE HINTS
Avoid inconvenience and service calls by checking these points before calling for service.
PARTS LIST
All parts are listed in the following Parts Lists. Parts may be ordered through nearest supplier
When ordering parts, first obtain the Model No. from the name plate on boiler, then determine the Part No. (not the Key No.) and the
Description of each part from the following appropriate illustration and list. Parts for which no Part No. is given are standard items which
can be procured locally.
Be sure to give all this information: The Part No., The Part Description, The Boiler Model No.
Fig. 22—Relationship of Set Points and Differential
A95611
10 F (5.6 C)
DIFF
110 F (43 C)
240 F (116 C)
25 F (13.9 C)
DIFF
10 F (5.6 C)
DIFF
SWITCH BREAKS ON
RISE, TURNS BURNER
OFF. CIRCULATOR
OPERATES ON CALL
FOR HEAT.
SWITCH MAKES ON
FALL. BURNER
OPERATES ON
CALL FOR HEAT.
SWITCH MAKES R-B
ON FALL, BREAKS
R-W. BURNER ON,
CIRCULATOR OFF.
SWITCH MAKES R-W,
BREAKS R-B ON RISE
(25 F [13.9 C]
DIFFERENTIAL).
SWITCH MAKES R-W,
BREAKS R-B ON RISE
(10 F [5.6 C]
DIFFERENTIAL).
HI LIMIT
SETTING
LOW LIMIT
AND
CIRCULATOR
SETTING
IF SYSTEM IS NOT HEATING OR NOT GIVING ENOUGH HEAT. . .
Possible Cause
What To Do
Thermostat is not set correctly
Reset thermostat above room temperature.
Boiler and/or burner may be dirty
Clean all flue passages and vent pipe. Have burner cleaned and readjusted.
Burner may not be firing at proper rate
Check nozzle size it there is any doubt. Have burner adjusted.
Burner may be short-cycling
Short-cycling (too frequent off and on) of burner causes sooting. If boiler and/or burner becomes dirty at
frequent intervals, correct the "dirt condition," then also correct the control setting (or other cause of short-
cycling).
Check thermostat heat anticipator and correct setting, if necessary, per instruction sheet packed with thermo-
stat.
No power to boiler
Check overcurrent protection. Check to be sure power supply circuit is on.
Controls out of adjustment
Reset according to instructions packed with controls.
Radiators not heating
Open radiator vents to vent excess air. Check flow control valve (if used). It may be in closed position.
Circulator pump not running
Check relay operation.
Poor electrical contact
Check all control terminals and wire joints.
IF BURNER IS NOISY. . .
Possible Cause
What To Do
Oil burner fan wheel may be dirty
Clean fan wheel with a stiff brush and cleaning solvent. Readjust oil burner.
Draft regulator may be stuck
Check to see if vane swings freely. Clean if vane is stuck.
IF RADIATORS ARE NOISY. . .
Possible Cause
What To Do
Air in system
Open radiator vents to vent air. Check expansion tank.
RELIEF VALVE LEAKING. . .
Possible Cause
What To Do
Dirt on seat
Open valve manually. Allow water to run and clear valve seat.
Waterlogged expansion tank
Drain tank. See instructions.
HAVE YOUR SERVICE TECHNICIAN CHECK ANY PROBLEM YOU ARE UNABLE TO CORRECT.
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