Pentair Mastertemp 250 heater that turns on, but shuts off after about 30 minutes

Jump to latest Follow Reply
R

rdbatk

New member
Jun 28, 2022
4
wisconsin
I have a Pentair Mastertemp 250 heater that turns on, heats the water (so gas is flowing), but shuts off after about 30 minutes, and red light shows up "service heater" There is no error codes. The heater is about 8 years old. I replaced the flue sensor about 4 years ago, and last year replaced the display. Any clue what that might be? There is plenty of water flow, filter is backwashed
 
Welcome to TFP.

Did you open the cover and flip the board over and watch if any diagnostic LEDs light when the heater shuts down?

Replace the thermal regulator and if it still fails replace the bypass valve in the header.
 
rdbatk said:
I have a Pentair Mastertemp 250 heater that turns on, heats the water (so gas is flowing), but shuts off after about 30 minutes, and red light shows up "service heater" There is no error codes. The heater is about 8 years old. I replaced the flue sensor about 4 years ago, and last year replaced the display. Any clue what that might be? There is plenty of water flow, filter is backwashed
Click to expand...
You don't indicate what controls the heater. Is it standalone or remote controlled?
 
I did replace the thermal regulator and the bypass valve, but the heater is still turning off. I do not see any lights on the back of the control display. I did forget to mention that after I turn it off, and turn it back on, it does the same cycling.
Any clues what it might be?
I wish an error code would show up on the display, which would pinpoint the problem.
 
Consider opening up the burner can and checking if the heat exchanger is leaking.
 
rdbatk said:
I do have the sides open of the heater off, and the burner can is not leaking.
Click to expand...
The sides only allow you access to the electronics of the heater. If you took the header bolts out and no water came out from the holes, then you probably don't have a leaking heat exchanger.
 
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply