4 Wire Old Honeywell Thermostat Wiring

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4 wire old honeywell thermostat wiring. In standard thermostat wiring the blue wire connects to the common terminal on the thermostat making it the c wire. You ll probably see a thermostat jumper wire connecting the rc and rh terminals. We have both a natural gas furnace and an ac unit. We have a 19 year old condo with an old carrier mercury thermostat.

Find out if your home is compatible with a honeywell home thermostat. Green the green wire connects to the fan. If the wire labels from your old thermostat hookup don t match the above honeywell offers additional advice that we adapt in table form provided in detail at honeywell 5 2 day programmable thermostat rth2300b1012 wiring. Honeywell thermostat wiring instructions from diy house help.

The wiring for your honeywell thermostat depends on the functions of your heating and cooling system. Red now there can be two separate wires for this. The model number of the honeywell thermostat was not provided however here are the typical wiring assignments for a conventional heating system. Honeywell 5 2 day thermostat wiring table.

4 wire or 5 wire thermostat wiring problem question. One is for cool and the other is for heat hence the abbreviation rh and rc. Revision history for how to wire a honeywell thermostat with 4 wires. References for honeywell thermostat 4 wire wiring diagram.

How to wire a thermostat from how to wire it. References for how to wire a honeywell thermostat with 4 wires. Keep in mind that there should be a low voltage cable in the wall where the thermostat is located which has individual wires as shown in the instructions below. There are only four wires going into the existing thermostat red green blue white.

It s there so you can supply power to the heating and cooling switches with a single wire which is usually red. In this configuration the blue wire acts as the return wire between the 24v transformer in the heating cooling system control panel and the thermostat. Blue this is your common or c wire.