I have a Pentair 150M CH MiniMax milivolt heater that won't shut off after its been running for a while. About 4 years old. Any help would be appreciated.
Heater Won't Shut Off
- Thread starter gfurman
- Start date
Sounds like a bad thermostat. It's going to keep running until it reaches the temperature you set it at, and if it doesn't think it's there, it won't shut off.
Thanks for your reply,
Except the on/off switch won't shut it down either...I have to cut the gas off.
Except the on/off switch won't shut it down either...I have to cut the gas off.
The schematic is in the manual if you're handy with a DVOM. http://www.pentairpool.com/pdfs/MiniMaxPlus&PowerMaxIG.pdf
If DVOM is an alien term, you're not handy with one.
If DVOM is an alien term, you're not handy with one.
I bought it new in Sep 2009, so the first time I used it was spring 2010....so five years I guess....
I'm handy mechanically to a degree and can replace parts....DVOM is indeed alien....some kind of meter?
I'm handy mechanically to a degree and can replace parts....DVOM is indeed alien....some kind of meter?
DVOM = digital volt ohm meter.
I was inside one of these last year and it seems there is a small board, if my memory is right, that has all of the connections for the thermostats, on/off switch and the millivolt connections for the gas valve. Maybe something amiss on that. Definitely sounds like there is a short in the wiring somewhere before the thermostats if switching off won't fix it.
I was inside one of these last year and it seems there is a small board, if my memory is right, that has all of the connections for the thermostats, on/off switch and the millivolt connections for the gas valve. Maybe something amiss on that. Definitely sounds like there is a short in the wiring somewhere before the thermostats if switching off won't fix it.
I missed the part about the on/off switch not shutting it down. Sounds like the control board is bad. Like danpik said, it's behind the knobs. I think you can still get this part.
I am thinking this is the part you "may" need...
Amazon.com : Pentair 471677 Millivolt Electronic Thermostat Replacement MiniMax CH and Plus Pool/Spa Heater : Outdoor Spas : Patio, Lawn Garden
Checking the circuits with a meter would verify this. I would also check the entire unit for some bad wiring that may have been chewed on by critters.
Amazon.com : Pentair 471677 Millivolt Electronic Thermostat Replacement MiniMax CH and Plus Pool/Spa Heater : Outdoor Spas : Patio, Lawn Garden
Checking the circuits with a meter would verify this. I would also check the entire unit for some bad wiring that may have been chewed on by critters.
Pool Clown
In The Industry
First, see if the thermostat select switch is even hooked up. If it is, disconnect it and see if the heater then shuts off. If it does, you either have a bad switch, or bad thermostat(s) or maybe the water is so cold that the temp setting wont go below the current water temp. What is the temp of the water?
The water temp is 88...I have no problem turning it on...
Thanks for the suggestions...I will get in there tomorrow and take a look at this board and the wiring. Thanks also for the part on Amazon...really appreciate the help fellows...
Thanks for the suggestions...I will get in there tomorrow and take a look at this board and the wiring. Thanks also for the part on Amazon...really appreciate the help fellows...
Pool Clown
In The Industry
Wait, Ok the only way to tun it off is the gas valve? Which valve? The one outside of the heater? or the valve inside with the wires and pilot tube coming out of it. Either way, i think the gas valve may be sticking. This time, try unplugging the wires from the gas valve to get it to shut down. If it remains on, its the gas valve.
Good thought...A volt meter would also be able to confirm if the power is being cut to the valve when the heat is satisfied.
