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How To Wire A Heat Pump Thermostat

How many wires do you need for a heat pump thermostat?

In heat pump system, there are at least 8 wires that need to be connected to the thermostat for proper operation.

Where does the white wire go on a heat pump thermostat?

The white wire underneath your thermostat connects to your heating system. It terminates at your air handler or furnace. The white wire connects to terminal W in industry-standard thermostats. If your HVAC system has multiple heating stages, then you may find more than one white wire.

What is the black wire on a heat pump?

This the Common Terminal, and usually, a blue or black wire is run to the transformer from this terminal to complete the circuit, and in some cases, provide power to the Thermostat. This terminal is found on thermostats designed to work with Heating Pumps and is used to power the defrost cycle on the heat pumps.

Does your heat pump use an O wire or B wire nest?

Your heat pump uses O and B wire. O wire shift the reversing valve from heating to cooling while the B wire does the opposite (Cooling to Heating). The O and B wires are easy enough to spot because they are ‘Orange’ and ‘Dark Blue,’ respectively.

What happens if you wire a thermostat wrong?

Potential consequences of improper installation could include: Electric shock. Blowing a circuit breaker. Damaging the thermostat unit, the electrical system or even the AC/furnace unit itself.

What color wire goes where on a thermostat?

This is the most typical thermostat wiring style, and it applies to systems that regulate both heat and air conditioning. The wires are typically arranged as follows: red for 24-volt hot, white for heat, yellow for cooling, green for the fan, and blue for common (although the common wire may be a different color).

What are the 4 wires on a thermostat?

4 Wire Thermostat Wiring (Heat Pumps, HVAC) Red wire for power (24V). White wire for heating (connected to W or W1 terminal). Green wire for fans. Blue or yellow wire for cooling (connected to Y).

What does white wire do on heat pump?

W Wire Terminal Designation – This color is typically white and goes to the W terminal. In a heat pump, this is for the backup heat source. Whether it is electric heat strips or a gas furnace (dual fuel), the W terminal controls this. This wire will also run to the air handler/furnace and the condenser.

What color is the C wire?

Blue wires are also called “C” wires because they are the Common wire. C wires are necessary for any “smart” thermostat that needs to be connected to a power source 24/7, regardless of your heat pump type.

What is the Y wire on a thermostat?

Y – This is the terminal for cooling or air conditioning and goes to the compressor relay. Typically a thermostat wire pull is made to the air handler on split systems and then this wire is spliced for the separate wire pull which is made to the condenser.

What is o’b wire on thermostat?

O, B, O/B: These wires are responsible for switching the changeover valve in a heat pump system. The O wire reverses the valve from heating to cooling, and the B wire switches the valve from cooling to heating.

Do I have O or B wire?

Look for connectors that have labels that are the same as your thermostat. For instance, you might find labels like R, W, G, Y, C or O/B. You should find wires attached to these connectors that are the same color as the wires that connect to your thermostat.

Should thermostat be on O or B?

The O/B terminal is for heat pump systems and is used for the reversing valve. When the “O” option/position is selected the reversing valve defaults to the heating mode. If the “B” option/position is selected the reversing valve defaults to the cooling mode.

Should my thermostat be on E or F?

The thermostat fan operation switch, labeled FUEL SWITCH in the diagram below, is factory-set in the “F” position. This is the correct setting for most systems. The “E” setting will allow the fan to turn on immediately with the heating or cooling in a system where the G terminal is connected.

Which wires are which on a thermostat?

Thermostat Wiring Tips The W wire is connected to your heating system. The Y wire is yellow and connects to your air conditioning compressor. The G wire is green and connects to the fan. Rc and Rh: The red wire(s) are the power source for your thermostat.

What is the common wire on a thermostat?

WHAT IS A C-WIRE? A C-wire, or a common wire, runs from your low voltage heating system (24v) and carries continuous power to your thermostat. In today’s electric market, most newer heating and cooling systems have C-wires, which guarantees compatibility for the installation of all smart thermostats.

Does R go to RC or RH?

Here are some general guidelines: An R wire can go into a Nest Learning Thermostat’s Rc or Rh connector. The Nest Thermostat E only has an R connector, which is typically where an R wire would go. These are not jumper wires, and you can insert the Rc wire into the Rc connector and the Rh wire into the Rh connector.