Heatnglo Goes off after 20 minutes

[Beach Dougie]

Model SL-950TR-DSIFixed the wiring issues with the insert. Can't imagine what the prior homeowner was up to.

Now...pilot is lite and stays on. But, after turning on fireplace from wall switch, it shuts off after 15 minutes. he pilot light remains on. No remote. I don't think theres a thermostat.

Before replacing the valve and thermocouple i thought i'd ask for advice. Help?

 

[DAKSY]

Did you take a reading of the millivolt output of the thermopile?

 

[Beach Dougie]

i will. do i have to remove it to measure that