Greenheck DG / DGX with Direct Spark (464043 IOM) (Pre-2008) - Manual (Page 34)

34
Troubleshooting
Troubleshooting
24 Vac across
terminals W1 and X?
Heat Switch (S3) Off
(Turn Heat Switch S3 On)
Heat Switch Not Wired
(Wire Heat Switch S3)
24 Vac across
terminals 22 and 21?
Main Transformer Defective
(Replace Transformer)
115 Vac across
terminals 26 and 21?
High/Low Gas Pressure Switch(s) Tripped
(Correct gas pressure and reset)
(Reference Direct Gas Start-Up Step #2)
24 Vac across
terminals 24 and 21?
High Limit (HLC) Tripped
(Reset/Replace High Limit HLC)
(Check on cause of control loss)
Continuity across
terminals 26 and 27?
24 Vac across
terminals 23 and 21?
Inlet Air Senor (TS) Holding
(Adjust TS1 setting -- Reference blower start-up step 6)
Heat Relay (RH) Defective
(Replace Heat Relay RH)
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Airflow Switch (PS) Holding for Proper Airflow
(Correct airflow across burner)
(Reference Direct Gas Start-Up Step #3)
Yes
At this time the heater should attempt to light
Heater Does Not Operate
Does not attempt to light (No visible spark)