I have a thermolec electric duct heater which is giving me grief and I need help.
I don’t have model and serial but I will look it up if needed. It runs on 600v and is used for make up air for hallways.

Thermolec controller has been changed out as well as defective contactor.
What I don’t understand is why I get changing readings for voltage and amperage on the heating coils.
For example on call for heat I get 28A then 16A, changing every second to half second back and forth. Third stage comes on at a steady 28 A.
The same happens with the voltage, 575V,0V, 575v.

I don’t understand why the controller is down stream of the heater. With 100 percent fresh air being pulled in is it supposed to

modulate and maintain a set temperature output?
I basically get air that is too cold or way too hot – no in between.
I have sent my question to the manufacturer and a a request for literature.

Would it not be better to have a stat in the hallway that only asks for heat when it is needed?