I am looking to put Nest thermostats in the house, I have now found out my entire house (one in each room, 6 of them) has been wired with HVAC Chinese
U12A UNIVERSAL A/C CONTROL SYSTEM urrgh – they have none of the connects Rh, C, W, W2 etc that Nest tells me to check for... this Chinese kit has just a board (HVAC controller?) and the display that plugs in to this board via a 10 pin unlabeled connector.
Will I need to replace the entire controller board (how much do they cost each), or do proper thermostats have all the controls built in and not need an external controller?
If so would it be a case of running wires down from the fan/compressor/valves to the new thermostat and hey presto or anything else i should look for?
The units wiring diagram is below: