How to Wire an AC Thermostat in an RV
by John Cagney Nash
In common with most coach accessories in an RV, the thermostat that controls the air conditioner (AC) is a regular household unit. The temperature controller built into the AC unit itself is pre-installed by the manufacturer and requires no user wiring. Wiring an AC thermostat becomes necessary when a remote thermostat is used to maintain a constant temperature. Installing this equipment is a straightforward project that will make your recreational vehicle more comfortable in hot weather.
Step 1
Consult the literature provided with the thermostat and the operator’s manual of your RV. Ensure the correct color-coded RV wires are connected to the correct numbered thermostat terminals. Normally, the terminals will have a screwdriver slot for securing the wires. The color-coded connections typically will be made as outlined in the following steps.
Step 2
Terminal 1 is typically ground to the vehicle’s neutral system. It will usually be black or blue. Use your voltage meter and the instruction literature that came with your RV and the thermostat to verify this.
Step 3
Terminal 2 is typically unused. Use the literature to verify this.
Step 4
Terminal 3 is typically hot, from the vehicle’s 12 volt system. It will usually be red. Use your voltage meter and literature to verify this.
Step 5
Terminal 4 is typically unused. Use the literature to verify this.
Step 6
Terminal 5 is typically the supply wire to the vehicle’s AC compressor. It will usually be yellow. Use your voltage meter and the literature to verify this.
Step 7
Terminal 6 is typically the supply wire to the blower fan’s high speed. It will usually be green. Use your voltage meter and the literature to verify this
Step 8
Terminal 7 is typically the supply wire to the blower fan’s low speed. It will usually be green. Use your voltage meter and the literature to verify this.
Step 9
Terminal 8 is typically the supply wire to the vehicle’s furnace or electrical heater. It will usually be white. Use your voltage meter and the literature to verify this.
Things You'll Need
- Thermostat
- Thermostat wiring instructions
- RV owner's manual
- Screwdriver
- Voltage tester
Writer Bio
John Cagney Nash began composing press releases and event reviews for British nightclubs in 1982. His material was first published in the "Eastern Daily Press." Nash's work focuses on American life, travel and the music industry. In 1998 he earned an OxBridge doctorate in philosophy and immediately emigrated to America.
