I have a new to me Eco 45 that I want to add a wall mount thermostat to. I have the "wiring diagram" such that it is, but, I cannot find anything that says which wire to hook to which terminal. There are only two terminals so I got a 50/50 chance of getting it right but my luck I hook it up backwards and blow the circuit board or something. Anyone know which terminal is white? Does it even matter? Thanks.