Old Furnace Thermostat Wiring

Upgrade from mercury to digital thermostat david jones.

Old furnace thermostat wiring. A large majority of homes today have an hvac system containing a furnace oil gas or electric and an ac unit. How to wire a thermostat. You out when connecting the wiring on the new thermostat. 4 wire or 5 wire thermostat wiring problem question.

Knowing what each thermostat wire does can help in wiring up a new or replacement room thermostat. To wire a thermostat you must first be aware of the type of system that you have in your home. These run from the thermostat to the furnace and control the heat in a home. There are only four wires going into the existing thermostat red green blue white.

To wire a thermostat of this kind basic electrical skills tools and safety techniques are required. This data can also be helpful if thermostat wires have become mixed up or improperly color coded by allowing you to trace wires back to their control connection point. By the use of an adjustable set point the job of the thermostat is to turn on either the heating or cooling system to maintain the desired room temperature in the home and to turn off the system when the desired temperature is achieved. How to replace an old home thermostat.

We have both a natural gas furnace and an ac unit. Reliablea perfect example of a common old thermostat is the. This article explains just what wire at a room thermostat actually controls. 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.

We have a 19 year old condo with an old carrier mercury thermostat. Back in the olden days thermostats were simple onoff devices that didnt need their own continuous power supply. Modern thermostats with wi fi and backlit display by contrast need a steady supply of juicethe c wire or common wire enables the continuous flow of 24 vac power to the thermo. The thermostat is the control device that provides a simple user interface with the internal workings of your homes climate control system.

Replace your old thermostat to remove unsightly discolored plastic housing or metal domed thermostats with sleeker more economical digital display thermostats. Thermostat wire reference chart. My paperback and e book. The thermostat wiring on these systems can have very similar wiring properties.