Hayward HeatPro Heat Pump Negative Temperature

[PoolInMN]

I have a Hayward HeatProd heat pump that I've had for several years. This winter an animal decided to chew through the wires that connect the water temperature gauge to the heater. As a result I had an error code P indicating that the water temperature circuit was shorted and the temperature on my control panel (not the heater itself) was showing an error.

I replaced the temperature gauge and that fixed the temperature display on the control panel but now the temperature on the heater itself is jumping around negative temperatures between -30 and -60 degrees which clearly isn't right. The heater itself kicks on for a few minutes, then turns off for a few minutes and then turns back on. As far as I can tell it never is actually generating heat.

So my question is can anyone call me why the temperature reading would be showing negative and if that might be related to the fact that the heater won't stay on?

 

[PoolGate]

Are you sure you got the right temp probe? If so, get another.

 

[PoolInMN]

Are you sure you got the right temp probe? If so, get another.

I wasn't 100% sure so I ordered another temp probe this time with the HPX2169 part number from the manual rather than a random temperature sensor. It turns out even with this correct temperature sensor it's still reading a negative temperature on the heat pump itself. The temperature on the control panel does however correctly show 78 degrees.

Amy other ideas what might be going on?

 

[PoolGate]

Can you put the heater in remote mode and have it ignore its own temp gauge and just be turned on/off by your automation? The only thing I can think of is that somehow the circuitry on the heater has been damaged. Are you sure no other wires have been chewed? Also most systems have at least 2 temp probes. One for water temp and one for heater temp. Make sure you replace them both. You may have 3. 2 for the automation and 1 for the heater.