[pss]

There was no ignition, the exhaust blower was running continuously and the control module red light was flashing.
After shutting power off for 10 minutes, furnace operation returned to normal. Any suggestions on what would cause the red light to flash continuously. This is a 21 yr old Tempstar.

 

[hvac5646]

depends on how many flashes....need the model number of furnace.

 

[pss]

Model is NULK075DG05. The red light was flashing ~1 every second. I now also notice the paper diag. on the inside of the upper cover is bubbling out in spots and that flame on start shoots out more than normal (rollout). Could the rollout sensor have caused the trip.

 

[pss]

Problem resolved. Dirty wire connection (24v) on the control module was preventing the gas valves from opening. After two failed attempts to light, the control module would then start flashing.