Can you join thermostat wire?

If you have to, you can splice the thermostat wire and generally, if the splicing has been done correctly, the thermostat’s function will not be affected. And as thermostats normally only need low-voltage power there are no safety regulations that prohibit the use of spliced thermostat wire.

Can you get electrocuted from a thermostat wire?





Virtually all room thermostats operate on low voltage that carries little risk of harmful electric shock. However, it is always wise to shut off power to a thermostat at the service panel before examining or working on it.

Can you electrocute yourself changing a thermostat?

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.

Do I need a jumper from R to RC?

If you just have one wire, regardless if it’s labeled RC, it will go into the R terminal, and the jumper connecting terminals R and RC will be in place. Some thermostats have a jumper switch, some have a metal staple, others may have a plug, and the jumper may also just be a wire connecting the two terminals.

How do you extend a thermostat wire?

Quote from the video:
Quote from Youtube video: The first step just cut this out. When you're stripping back thermostat wire. This is just typical 18:8 South wires number set wire and when you're stripping it back I want you to snip into the end.

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.

Can thermostat wire start a fire?

The safety commission reports that contact between the thermostat wires and household line voltage can damage the thermostat and cause a fire.

Does thermostat get power from furnace?

Most room thermostats on heating and cooling systems receive their 24V AC electrical power from a low voltage transformer that itself is usually found at the boiler or furnace (blue arrow in our photo at left).

Do thermostat wires have voltage?

Quote from the video:
Quote from Youtube video: Going to each terminal. If you look at my wiring video that I have posted on my channel you'll see here this is our red this is our voltage 24 volts coming down to the thermostat.

Why is there a jumper between R and RC?



In most cases, the heating and cooling system share a single transformer by leaving the jumper in the lower right corner it connects the RC and RH to power heat and cool features.

Do I need a jumper between RH and RC?

Instead of using jumper wires, Nest Learning Thermostats use an internal jumper between the Rh and Rc connectors. A Nest Learning Thermostat will automatically use this internal jumper if your system needs it. Important: Never put more than one wire into a Nest thermostat connector.

Should RC and RH be connected?

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.

Does red wire go to R or RC?



There is no standard for the colour of the RH wire, but most units use a red one. The RC wire, on the other hand, refers to “red cooling”. It’s the same with the RH wire in that it powers the thermostat. For the RC, it powers the cooling system.

Is RC wire same as C wire?

Typically, the wires that provide the power (often called the “hot” wires) are labeled Rc (cooling) and Rh (heating). They provide a source of 24V power coming from the HVAC control board. Sometimes they are separate wires and require separate connections. Other times they are the same wire.

What is the difference between RC and RH 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.)

Where do thermostat wires go on furnace?

Quote from the video:
Quote from Youtube video: Inside the furnace you see that we have a W and R a Y a G and a C and so those are located on the control board inside the furnace the terminals for the thermostat or W. That's for heat Y.

What is the purpose of the C wire on a thermostat?



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.

Where does the C wire go on a furnace?

Quote from the video:
Quote from Youtube video: The common terminal is going to be right here so if you're installing. Something you would stick the wire. Into this screw terminal from the bottom.

How do you wire a C wire to a furnace?

Quote from the video:
Quote from Youtube video: One of these is gonna be Diggs wires they go to the thermostat. One of these is gonna be the wires that go to the AC compressor. And they come in through the top here.

Can I use the G wire for the C wire?

Option #3: Use a G-Wire as a C-Wire



If there is no hidden C-wire, you can use a G-wire instead. However, you will not be able to use your fan independently when the heating or cooling isn’t running. Also, many HVAC systems are incompatible with this solution, including: HVAC systems using electric heat.