Let’s take a look at the G wire. This wire will go to the G terminal on your new thermostat. For the Y, Y1, and Y2 wires, Y or Y1 will go to the Y terminal, and Y2 will go to the Y2 terminal. The O/B wire can have many configurations.

What color is the Y wire on a thermostat?

MarkingWire Color CodeDescriptionCBlack/BlueCommon of 24 Vac transformerWWhitePrimary heat cell relayEBrownEmergency heat relayYYellowPrimary cool call relay

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 is the difference between Y1 and Y2 wires?

In conventional cooling systems, Y/Y1 controls the first stage of cooling and Y2 controls the second stage, which helps cool down the home faster. In heat pump systems, Y1 controls your compressor, which heats and cools your home.

What color is ob wire?

It’s usually blue, but it may also be black, brown or purple. The O or orange wire connects to your heat pump (if applicable).

What are the 5 thermostat wires?

• 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).
• Black wire for “C” or “Common” wire.

What is the OB wire on a thermostat?

The wires are used to switch the changeover valve in a heat pump system. The O and B wires switch the valve from cooling to heating. It could be a single O/B wire.

Why is there a jumper between R and RC?

Effectively there isn’t a second RH wire, although there is an RH terminal. However, the heating still needs to be controlled, so a wire known as a jumper is connected between the RC and the RH terminals so that power gets to the heating control part of the thermostat.

Where does Y2 wire go on thermostat?

The Y – (Yellow wire) This wire is from air conditioner units (cooling side); it comes from the compressor relay and goes to Y terminal in thermostat subbase. Y2 is the thermostat wire for second stage of cooling.

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.

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Why is my AC blowing hot air after changing thermostat?

If your AC is blowing hot air, the thermostat may have been accidentally set to “heat.” If this is the case, it’s easy to fix on your own. Simply flip the thermostat setting back to “cool” and see if the air conditioner begins to blow cool air again.

Can you change a thermostat without shutting off power?

The short answer is no, it’s not OK – you increased your risk of electrocution and that’s never a good thing specially for a DIYer.

What does the RH wire do on a thermostat?

The RH wire refers to “red heating” which means that this is the connection you need in order to power the heating system of your air conditioning unit. Yes, even your air conditioning unit has a heating system to keep the temperature in balance.

Why does my thermostat have 6 wires?

If your system has six wires, it’s because it features second-stage heating, second-stage cooling or heat-pump cooling but not all three. The extra wire signals the additional function to come on. If your system has second-stage heating and cooling as well as a heat pump, then the thermostat needs eight wires, not six.

What does RC and RH mean on a thermostat?

RC: The RC terminal is the 24-volt cooling power supply. RH: The RH terminal is the 24-volt heating power supply. (Note: The RC and RH terminals are jumpered together in a four-wire heat/cool system and a single-stage heat pump system, but not in a five-wire heating/cooling system.)

How do you wire a 2 stage thermostat?

Connect the wires of the 2-stage thermostat to the household wires. Connect the red wire to the “R” terminal of the thermostat; the brown wire to the “W2” terminal; the black wire to the “C” terminal; the yellow wire to the “Y” terminal; the green wire to the “G” terminal; and the white wire to the “W” terminal.

What does Stage 1 and 2 mean on my thermostat?

The second stage is the full capacity of your system. 1/3 compressor capacity is the 1st stage. 1st stage is more efficient than 2nd stage, but systems are designed to use both stages, so no worries there.

What's the difference between a single stage and two stage furnace?

A furnace with single-stage heating contains a fixed gas valve and a single-speed blower motor. … A model with two-stage heating contains a two-stage gas valve and a variable-speed blower motor. This allows the furnace to run at a lower setting in milder weather and a higher setting in very cold weather.

What does W e mean on thermostat?

W: Auxiliary heat, stage 1. E: Emergency heat (In emergency mode “Y” is not energized and E is energized to indicate the need for emergency heat. This mode is used if the heat pump fails during cold winter temperatures and the compressor must remain off.)

Does the red wire go to RC or RH?

If you have both an Rh (Red-heat for powering the heating) and an Rc (Red-cool for powering the cooling), then the R wire can be connected to either Rh or Rc. … If you only have a single R wire, then it will only have an R connector, which is the connection you’ll use.

What is the F terminal on a thermostat?

Thermostat Wire ID Tags or ID of Connector Terminals in a Room ThermostatPossible Wire ID Label or Connection Point ID Label on ThermostatControl Function / Connection Point for This WireFF – Fan controlGG – Fan control In most thermostat hookups the green wire is used to control a fan.HH – external humidifier control

Should my thermostat be set on gas or electric?

With it set to gas the furnace controls when the fan comes on. When set to electric the thermostat activates the fan. With electric furnaces the fan should come on right away. If there is a delay or the fan doesn’t come on at all then you have a problem.

What are the switches on the back of a thermostat?

In non-digital thermostats there are two switches. These switches move small metal balls that make contact between different traces on the circuit card inside the thermostat. One of the switches controls the mode (heat or cool), while the other switch controls the circulation fan.

What do I do if my AC isnt blowing cold air?

Try cleaning your air conditioner’s filter and the coils to see if improving the airflow fixes the problem. If there is ice buildup, you’ll need to run the unit with just the fan in order to melt it off. If that doesn’t get the unit blowing cold air again, it could be refrigerant levels are low (see below).

Why is my air conditioner running but not cooling the house?

Condenser Unit is Blocked If your air conditioner is running, but not lowering temperatures inside, one issue could be a blocked or clogged condenser coil. When operating correctly, the condenser fan draws air into the outdoor unit through the condenser coil to pull heat energy out of your home.

Why is my AC blowing hot air instead of cold?

If your air conditioner is blowing out warm air, your unit’s refrigerant levels might be low. This usually indicates a refrigerant leak in your system! If that’s the case, your air conditioner will continue to run and blow out warm air, trying to reach the temperature you set on your thermostat.

Can I get shocked from thermostat wires?

Virtually all room thermostats operate on low voltage that carries little risk of harmful electric shock. … Don’t tamper with a thermostat that controls an electric baseboard heater; these usually carry full-strength household current and can deliver a fatal shock.

Is it safe to touch thermostat wires?

Best policy is ; don’t touch any wires on any stat. In the USA residential thermostats is normally low voltage 24vac so you will not receive a shock from these wires but when servicing or replacing a thermostat it is wise to disconnect power to the HVAC unit so there is no unexpected control operation to the unit.