AC low voltage question, the red and white compressor wires connect to what tstat wires?

Question

The tstat wires go into the unit to a board and the compressor unit wires from outside come to the same board. My red and white compressors broke and I dont know what to connect them back to I think the white goes to constant (no tstat wire connected) and the red goes to the yellow from the tstat.

Answer 1

for a heat pump in usa,

red stat wire is usually one of the 24 VAC line

blue is the other 24 VAC line

green is the fan

yellow is the outdoor unit

orange is the reversing valve

white is for emergency heat

a lot of modern stats do not use blue(they cheat by leaking microamps thru a relay)

the problem is that none of the colors is really standard. they are commonplace. if you have a meter or can find the 24 volt transformer, you will usually not "blow anything up" by misconnecting.

if your stat has red and blue, use the meter to check the voltage between them. if it is 24 volts, don't connect anything directly to blue. or find the transformer and check the  wire colors. two will be the 120 VAC source(usually black and white with thicker insulation), the other two will be the 24 VAC.

be careful. 24 VAC will not hurt you but the 120 volts can and will.

Answer 2

It depends on your thermostat. If you have two wires from indoor units to condensor then white is c or common and red should connect to y yellow.

Answer 3

You have it right, one wire to C or common and the other to Y or cooling.