Pentair MiniMax Short Cycling

[ssmith579]

My MiniMax heater is short cycling. On for about 30 seconds then off about the same. I removed the flow switch and it seems to ne operational. Not sure how to test it. I checked the outputs and get 9.25K ohms between them whether the water is flowing or not. When unplugged the heater doesn't start at all and if I short the inputs to the control board it doesn't start either. Anyone know what the output of the switch should be? I'm not sure how to verify if the switch is bad.

Thanks,
Steve

 

[ps0303]

A pressure switch won't short cycle the heater. It would prevent it from coming on if it indeed has failed Is this a MiniMax NT?

 

[CraigMW]

Do you know that your heater is getting adequate gas pressure? I had a similar problem, and had the gas company out. They informed me that our old gas line to the pool heater was corroded and needed to be replaced. This was a bit pricey to do, but faulty gas lines are not something one wants running through your backyard! The MiniMax has a series of fault codes that can be determined by looking at the control panel as well as the control board. You should search for the MiniMax repair manual online for more info.

 

[ssmith579]

Figured it out. It was the high limit switch shutting it off. Took the header off, cleaned everything, re-seated the limit switches and now the heater stays on.