Hello. I have a heatnglo gas fireplace (nat gas) that won't fire up (worked fine last season). It has the intellifire rc300 system for lighting the pilot and then the main burner once the pilot flame is detected. I am using this in non remote mode (i.e. the remote is not the issue). This is what I am seeing:

I turn the control module to on and the pilot lights. After a few seconds of flame detect, the sparking stops. At this point, the main burner should light but never does, however the control module beeps indicating all is well. The pilot will stay lit forever (until I turn the control module off).

I happen to have 2 fieplaces with the same rc300 controller. The other fireplace works as expected so I swapped the control module and the fireplace that was working is still working, and the one that isn't still does not, so I have ruled out the control module as an issue.

Per trouble shooting instructions I found online, I measured the gas valve voltage for the main burner and I get the expected 1.6 v to open the main valve, and then the 0.3 v to keep it open. I also ohmed out the solenoids for the pilot and main burner and both are within limits.

Any other ideas as what could be wrong? Anything else I could try?

For anyone else who may run into this, I figured out my issue. The gas valve was NOT properly grounded. I'm assuming the ground wire must have shifted during the summer season such that the connection was not a good one. Once I removed it and then reseated it (and checked for good continuity with my multimeter), the fireplace fired right up as expected.

FYI - to test the gas valve before I looked at the ground, I took a batter pack with a few AA batteries in it and connected the positive to the main valve connection, and the negative to the valve body and the valve opened right up. Once I figured out the valve was in fact working (and ruled out everything else per the above post) it seemed like the ground was the last viable option.