Reported Issue: Inaccurate temperatures on PowerCor tanks.
Conclusions: After testing in our labs, one possible scenario was discovered. If the insulation was trapped between the thermostat and the tank, then a gap was created between the back of the thermostat and the storage tank. There should not be a gap between the rear of the thermostat and the tank body.
Resolution: Inspect the thermostat area. Make sure the insulation is not interfering with thermostat mounting and none is present under the thermostat itself. Also, check to make sure the foam is not putting excessive pressure on the wiring to the thermostat, pushing the wires and the thermostat out of their proper location.