Its tripping with the thermostat on I believe.

If the unit is to stay powered at all times then how does the temp get set? The only switch is a on off switch that is also labeled fan/heat with stickers so its a little ambiguous.

I expected an internal setting for temperature and there wasn't, so leaving it powered at all times would be costly for a 5kw heater.

Even with a external contactor connected to the thermostat would yield the same results.

I will take another look and try and see if I can see anything else.

Would a thermostat with fan control be suggested?

I appreciate the help... many thanks