I have a 1 kw immersion heater installed in my home that runs on electricity. Also installed is a 5 kw solar PV system on our rooftop as well as 5 kw single phase inverter. Recently we got a solar pv load controller switch installed in our home to optimize most of the power that the summer's shine gave us. We got it configured to divert excess to the immersion heater and an additional inverter. First the immersion tank heats up and then any extra goes to the inverter. The diverting happens only when the thermostat in the immersion tank cuts off. Lately there was no power going to the inverter and we checked the immersion tank. We called the controller switch company and got it checked. The device is doing fine but the inverter is not receiving power. We checked the wiring, it is fine. What could be the reason? I have a doubt of the thermostat not working properly. How do I check this?