4 Wire Thermostat Wiring Diagram Heat Only. Basic heat pump thermostat wiring and wire colors for thermostat wires. 4 wire or 5 wire thermostat wiring problem question.
The basic heat a c system thermostat typically utilizes only 5 terminals. Because they only have one function they are 2 wire thermostats usually consisting of a red wire for power and a white wire for heating. Thermostat installation wiring diagrams.
A heat only thermostat is a home thermostat which can only heat the air temperature and not cool it down.
We have a 19 year old condo with an old carrier mercury thermostat. 4 wire or 5 wire thermostat wiring problem question. R red wire to the r terminal. Thermostat installation wiring diagrams.