Pentair Mastertemp 400 Troubleshooting
If you are having problems with your Pentair Mastertemp 400 Pool Heater, you are not alone. Many Pentair Mastertemp 400 owners experience issues with their pool heater from time to time, and it can be frustrating to deal with these problems.
Pentair Mastertemp 400 Pool Heater Problems
Pentair Mastertemp 400 Replacement Parts
Troubleshooting a Pentair Mastertemp 400 Pool Heater
Share your Pentair Mastertemp 400 Pool Heater Problems, issues , tips, ideas, and frustrations with other owners.
Heater comes on but won’t get on higher than 79 degrees
I’m struggling! I have an issue with my Master temp 400 NG shutting down at 85 and the service heater light blinks for about a minute and then the heater starts up again for a few minutes. Andthen shuts down again and again. I am trying to heat the spa to 100 deg. I have replaced both sensor’s and have water tested the thermal coupler by running it under hot water and seen it open and close at the proper temperatures. My water pressure is 25 psi. My next move is replacing the circuit board which lights up when it shuts down. “Please Help”. Make me a believer in this heater that gets good reviews.