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Burner Troubleshooting
Table 9 - Burner Troubleshooting Chart
Problem
Potential Cause
Corrective Action
Pilot Does Not Light/Stay Lit
Main gas is off
Open main gas valve.
Air in gas line
Purge gas line.
Dirt in pilot orifice
Clean orifice with compressed air.
Gas pressure out of range
Adjust to proper gas pressure.
Pilot valve is off
Turn pilot valve on.
Leak at pilot orifice
Tighten pilot orifice.
Excessive drafts
Redirect draft away from unit.
Safety device has cut power
Check limits and airflow sensor.
Dirty flame sensor
Clean flame sensor.
No call for heat
Adjust heat setpoint.
No spark at igniter
Check wiring, sensor, and ignition
controller. Check spark gap, refer
to
on
.
Main Burner Does Not Light
(Pilot is lit)
Defective valve
Replace combination valve.
Loose valve wiring
Check wiring to valve.
Defective flame rod
Replace flame rod.
Shut off valve closed
Open shut off valve.
Defective flame safety controller Replace flame safety controller.
Pilot fails as main gas valve
opens, and main gas flows.
Plug the first burner port next to
the pilot gas tube with burner
cement.
Not Enough Heat
Main gas pressure too low
Increase main gas pressure - do
not exceed 14 inches wc inlet
pressure(5-14” wc).
Too much airflow
Decrease airflow if possible.
Burner undersized
Check design conditions.
Gas controls not wired properly
Check wiring.
Heat setpoint too low
Increase heat setpoint.
Thermostat malfunction
Check Wiring. Replace
Thermostat.
Unit locked into low fire
Check wiring.
Too much heat
Defective modulating gas valve
Check/replace modulating valve.
Heat setpoint too high
Decrease heat setpoint.
Unit locked into high fire
Check wiring.
Thermostat malfunction
Check Wiring. Replace
Thermostat.
Содержание D76
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