I have an ultra temp heat pump that says the actual water temp is the same as the set temp of 104 on the heat pump panel. I was under the impression that this panel was inactive because everything is connected to the Easy Touch automation. Pentair told me to try to replace the thermistor. I can see it looking down from the fan. Is that something I can change or do I need a pool repairman? It looks complicated removing to remove the cover to get to the thermistor. Thanks