CleaverBrooks CBLE, Operation And Maintenance Manual

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Troubleshooting
7-2 750-91 (revised 2009)
Model CB-LE Packaged Boiler Manual
The program relay has the capability to self-diagnose and to display a code or message that indicates the failure
condition. Refer to the control bulletin for specifics and suggested remedies.
Familiarity with the programmer and other controls in the system may be obtained by studying the contents of this
manual. Knowledge of the system and its controls will make troubleshooting much easier. Costly downtime or
delays can be prevented by systematic checks of actual operation against the normal sequence to determine the
stage at which performance deviates from normal. following a routine may possibly eliminate overlooking an obvi-
ous condition, often one that is relatively simple to correct.
If an obvious condition is not apparent, check the continuity of the circuits with a voltmeter or test lamp. Each cir-
cuit can be checked and the fault isolated and corrected. Most circuitry checking can be done between appropriate
terminals on the terminal boards in the control cabinet or the entrance box. Refer to the schematic wiring diagram
for terminal identification.
Problem Possible Cause(s)
BURNER DOES NOT
START
1.
No voltage at program relay power input terminals.
A. Main disconnect switch open.
B. Blown control circuit fuse.
C. Loose or broken electrical connection.
2.
Program relay safety switch requires resetting.
3.
Limit circuit not completed - no voltage at end of limit circuit program relay
terminal.
A. Pressure or temperature is above setting of operation control. (Load
demand light will not glow.)
B. Water below required level.
1) Low-water light (and alarm horn) should indicate this condition.
2) Check manual reset button (if provided) on low-water control.
C. Fuel pressure must be within settings of low pressure and high pressure
switches.
D. Oil fired unit - burner gun must be in full forward position to close oil
drawer switch.
E. Heavy oil fired unit - oil temperature below minimum settings.
4.
Fuel valve interlock circuit not completed.
A. Fuel valve auxiliary switch not enclosed.