Honeywell Thermostat T841A Wiring
- 1). Loosen the screws on the the Honeywell T841A Thermostat's terminals. Pull the wires through the back. Use wire strippers to strip enough cover from the wires to give you about 1/4 inch of bare wire for each one.
- 2). Inspect the Honeywell T814A's terminals on the wall plate and find the markings. There are up to 10 terminals in this thermostat to control different types of climate-control systems. These terminal markings will be G, R, W2, E, B, X, Y,W1, L and O.
- 3). Your wiring should be ordered in a standard color-coding system. The green wire goes the G terminal, red goes to the R, blue goes to the B terminal and brown goes to the X terminal. The white wire goes to the W2 and should have a jumper attached from this terminal to the E terminal. The yellow wire goes to the Y terminal with a jumper over to the W1 terminal. The O is a changeover relay for cooling and the L is for a system monitor. Neither of these last two have standard colored wires.
- 4). Insert the end of the red wire into the connector on the R terminal on the T814A. Screw down the connector tightly and give the wire a slight tug to ensure it is secured to the wall plate.
- 5). Install the remaining wires into the corresponding terminals as described in Steps 3 and 4, tightening each connector as you go.
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