Help with Pentair Mastertemp debug

[jeffast]

Hello,

My heater stopped working over the winter and I am trying to figure out why. I do run the pool year round. We did have freezing temps, but not as bad as prior years. Worst year no power for a few days, everything froze but mostly all came back to life (I did disconnect pipes etc). Anyway, on to my current issue.

I read through the operation guide. Here is what I see.

Initially the error code was AFS. The unit would sort of cycle every few seconds. I took off the covers to inspect the Air Flow Switch, but the unit decided to throw a AGS code instead.

The unit now reliably trips to AGS. There is a good amount of airflow from the exhaust port. The air never seems to be warm in any way. I did bypass the filter to help with water flow, but it does not seem like this is the problem. Is there some other reason for AGS other than overheating?

This link should show a video of the startup.

New video · Thursday, May 8 ð¬

Tap to view!

photos.app.goo.gl

Thanks,
Jeff

 

[ajw22]

How long does the heater run before throwing the AGS error?

Read Pentair MasterTemp Heaters - Further Reading

 

[jeffast]

In the video around 45 seconds. No heat at exhaust.

 

[1poolman1]

In the video around 45 seconds. No heat at exhaust.

Propane or natural gas?
If there is never heat at the exhaust, or flame in the combustion chamber (you can hear a heater light all that gas), your heater is not lighting. Could be a bad ignitor. Could be the main gas valve was shut off (small lever on the top). The AGS (automatic gas shut-off switch) is designed so that gas does not continue to flow with no ignition.
Do you hear the gas valve open, a "metallic click?" Do you smell gas in the exhaust? You should if the main valve is opening. Valve could be bad.
Is the exterior gas cock (valve) closed? If propane, is the valve on the tank open?
I have gone on many "service calls" for just that reason, someone turn off the gas. Yes, I charged because I always ask if that has been checked before I make the trip.

 

[jeffast]

It's propane. A whole house buried tank, so I know it's working. No smell of propane. Sounds like it could be the valve. Will listen for the click. But yeah makes sense if the AGS can also trigger if no flame detected.

Thanks,
Jeff

 

[ajw22]

But yeah makes sense if the AGS can also trigger if no flame detected.

I expect you will get IGN error, not AGS with no flame detected.

AGS indicates 140 degree water switch has opened causing gas valve to shut.