Pentair MiniMax 400 not starting

[AustroTom]

Hello All,
We have a 2005 Pentair MiniMax 400 that doesn't want to fire up when turning on heat, either insde the controller, or outside in service mode.
The LEDs AUX and PRESS are NOT on, and oddly reading the indoor panel, the spa temp says 112 deg. (which is clearly not the case).
Any ideas? Is it the pressure switch, thermostat, temp sensor?
PLease help.
Thank you,
Thomas

 

[AustroTom]

If the pool temp and spa temp says 120 degrees (although of course it isn't) could that be the culprit for my heater problems?

 

[AustroTom]

Could it be the temperature probe at the manifold?

 

[1poolman1]

Hello All,
We have a 2005 Pentair MiniMax 400 that doesn't want to fire up when turning on heat, either insde the controller, or outside in service mode.
The LEDs AUX and PRESS are NOT on, and oddly reading the indoor panel, the spa temp says 112 deg. (which is clearly not the case).
Any ideas? Is it the pressure switch, thermostat, temp sensor?
PLease help.
Thank you,
Thomas

If the indoor panel reads 112, the automation will not allow the heater to fire. That is the automation's temperature sensor reading a wrong temperature. It is in either the pipe between the pump and filter or the pipe after the filter.

 

[AustroTom]

So it could not be the thermistor?

 

[1poolman1]

So it could not be the thermistor?

It could be, but you need to take the automation out of the equation to be sure. It interrupts the control circuit. If the automation reads 112 it will NOT allow the heater to fire. No lights will appear on the heater.

 

[AustroTom]

Stupid question: ar eyou talking about the probe thats attached to the pvc via a hose clamp?

 

[1poolman1]

Stupid question: ar eyou talking about the probe thats attached to the pvc via a hose clamp?

That is the water temperature sensor that tells the automation the water temperature. It is not reading correctly if the automation says the water is 112 or 120 and it isn't even close.

 

[AustroTom]

Is there a test i can perform to see if that's the faulty part? Like bypassing?

 

[1poolman1]

Is there a test i can perform to see if that's the faulty part? Like bypassing?

No.

 

[AustroTom]

I received the temperature sensor today and installed it right away.
Works like a charm! Thank you so much for your help.