Based on many threads I have researched (all for Criterion II), the flame sensor is in front of left burner. Mine doesn't have it there.I have an older model. There is a rod the goes across both burners. But I have my doubts if this is it because I don't see any wires connected to it. So how would it communicate with main board about flame?
Anyway, please see picture and tell me if that is in fact it or if I'm missing something.


I'll describe my problem to see if anyone has any other ideas. Although based on what I have read I think I need to clean flame sensor once I find it.

Hot surface ignitor in front of right burner turns on as normal (brand new, i just replaced it). After a few seconds of it being on, the 2 burners turn on for 2-3 seconds and shut right off.
That is what happens most times. After trying many times I did notice a few times the ignitor would light up and then after a few seconds turn off before the flame could start. but most of the time the flames do turn on.

Really need help on this one as I completely stumped at this point.

 

Probably combination igniter and flame sensor. How many wires are going to the igniter?

 

Ah ok. That would make sense. There are 2 wires
If this is the case, any other ideas of what I could try?
I have new igniter, new air filter.
So that eliminates those possibilities.

 

Some furnaces used the hot surface ignitor for flame proving. The ignitor only had the normal 2 wires. If this is what you have, make absolutely sure the grounds are all clean & tight. Can you provide a model number of the furnace?

 

Model number is RGLG-05NAUER

 

The info on the RGLG series is lacking.

From what I can find so far is that does use the HSI as the flame sensor. It looks like there may have been problems with the combo as the new control board no longer uses the HSI to sense flame but uses a supplied sensor rod that needs to be installed.

 

I can't find anything with that model number...

Post a picture showing the burner area below that black gas pipe.
If you have a flame sensor it may be below the burners.

 

That furnace uses a direct spark.... the OP's is an HSI.

Hey.... just to get a little off topic.... why don't they use more direct spark ignition systems ? The HSI is so wasteful.

 

Seems like both Criterion 2 models have a flame sensor. A lower picture of the burners might reveal a flame sensor if one is present.

The newer low voltage hot surface ignitors pull 1/10th the amperage of the older 120 volt 3 amp models when I measure them on MC heat checks.

I don't miss the old intermittent pilot modules locking out and causing the answering service to give me a ring at night.

Our beeper guy is like the Maytag man in the old commercials in the winter time.

 

That spot almost looks like it could be a sensor location.