Heater shuts off before reaching desired Temp

[robirwin]

Hello,

I have a large pool and spa. The heater is a MiniMax Plus 400. Everything seems to work properly except the heater shuts off around 90 degrees instead of the temp it set to shut off at the remote control station of 100 or even 105. So it will heat up until about 90 then just act like it is at the desired temp when it is not. I also try turning the system off and then going to the Maintenance station by the pool equipment - makes no difference the heater won't turn on afterwards. If I switch the heater from spa to pool (which has cold water) then the heater comes on.

thanks for you help!

Rob

 

[jblizzle]

Welcome to TFP!!!

Sorry for the delayed response, although I am not sure I will be much help.

Am I to understand that you are running it through an automation system? What does the water temperature read on the remote and at the equipment? Have you used a separate thermometer?

I am wondering if there is some conflict between what the automation system thinks (which has its own temp reading that is used to turn the heater on/off) and what the heater thinks the temp is (the heater has its own reading that is used without automation systems).