Does the relay have 3 wires for the contacts? If I understand you correctly it is also a temperature sensor. Besides the common lead, if there are connections for both normally-open and normally-closed contacts then you may have it wired to the wrong contact where the fan is turning off at 180 instead of on. Just a thought. I think I'd be talking to the manufacturer next. Keep me posted.
I'll be back in a couple of days. My daughter is taking me sailing for Father's Day. jerry
