I have a very old heater that has a 3rd party digital thermostat built into it to control the temps better for the attached spa. Sort of like an aftermarket thermostat
The probe for the thermostat is in a return side pipe right before the water flows into the heater.
Its after the water flows through the basket, multiport, and is filtered.
This works very well, but the temp of this device is consistently showing about 1.5-2 degrees cooler than the pool thermometer is saying.
My question is... If I move this probe closer to the suction valve. Maybe before the water even goes through the pump basket. Can I possibly get a more accurate result? In other words, is it possible the water is cooling down a bit during the filtration process? Thanks a million!!