Power Shot (A.O. Smith) doesn't switch on automatically

[xrt678]

My gas water heater switches off before the water has been properly heated to temperature and/or doesn't automatically switch on when it should (like after a shower and running the dishwasher). It's about 9 years old, 50 gallon.

What I have been doing is manually switching off the power vent and then switching it back on. For some reason, this kicks the thing into gear and it begins heating.

However, sometimes it turns itself back off before the water is to temperature. If I toggle the power vent switch on/off over the course of, say, an hour, then the water is good to go. When the water is hot and I toggle the power vent off and on, it doesn't come on. Which makes sense.

...but to add to the confusion, sometimes I don't have to do anything and it comes on on its own and heats the water properly.

Any ideas?

 

[WorthFlorida]

Google search Power Shot (A.O. Smith) and there is all kinds of info. I know nothing about this water heater but is there a safety switch for the air inlet damper so it will only turn on the burner when the damper after it has been opened?

Here is a 1993 training and troubleshooting document. www.hotwater.com/lit/training/tc10.pdf

 

[Sponsor]

 

[xrt678]

Thank you! I think I'm getting closer to finding the answer.