It’s a bit high but whether it will be a problem depends on your thermostat and how it tolerates the high voltage. Also consider that the furnaces controller board is also receiving this voltage. Before you start anything else, check to see if your thermostat can be calibrated and complete this step first.
What voltage should be on the C wire?
24v
A C-wire, or a common wire, runs from your low voltage heating system (24v) and carries continuous power to your thermostat.
How do you test AC wire thermostat?
Quote from the video:
Quote from Youtube video: Begin by putting one probe whichever probe you want on the rh wire and test every other wire with the other probe. One of the wires will show up is 24 volts and that is your c wire.
How many volts can thermostat wire carry?
The thermostat wire is sized for mechanical durability, not for current carrying capacity. Codes may require the circuit to be Class 2, 30 volts and 100 VA maximum, usually 24 volts and no more than 4 amps. It could be much less than 4 amps and most of the capacity may be required for the relays in the HVAC unit.
What does the C wire control on a thermostat?
The C wire, or “common wire” enables the continuous flow of 24 VAC power to the thermostat. Technically speaking, power flows from the R (red) wire, but not continuously (not on its own, anyway). To make it continuous requires a common wire to complete the circuit.
What color is C wire for thermostat?
Blue wires
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.
How do I know if my C wire is working?
You should see 24 Vac. It could be as high as 29 Vac when nothing is running, and nothing will be with your thermostat removed. If you have the voltage then the C wire is real and you can continue. If not consider having your system updated to include it.
Why is my C wire not working?
Quick Check for an Existing C-wire:
If it has batteries, remove them. If the thermostat loses power it does not have a C-wire, and you may need an add-a-wire kit. If it doesn’t lose power, locate your breaker panel. Flip the breaker for the wall with the thermostat on it.
Can Nest thermostat work without C wire?
According to the Nest website, your Nest thermostat will work without a C-wire but specialists still recommend using an adapter if you can’t get a C-wire installed. If your Best thermostat will not receive a constant flow of power, it might not work properly and it runs out of power it will not work at all.
How long is a strand of C wire?
Blade size: length=65 mm, width=21 mm. Spacing of blades: 100 mm C/C. Coil diameter: 3′-2″ or 960 mm.
Can I use G wire for 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.
Is C wire a ground?
No way! A “return” is not the same thing as a “ground”. In certain situations it is, but not here. The C wire (together with “the other half of the circuit”) forms a circuit through the secondary of the 24V transformer.
Can I jump R to C on thermostat?
C is a common neutral wire. You can’t jump it from Rh as that is a 24v wire. You need a third wire, C, to return to the unit and hook to the common side of the transformer. For ease of thought, think of R as “hot” and C as “ground”.
What is the yellow wire on a thermostat?
Yellow thermostat wires are responsible for controlling your air conditioning system through the compressor. They connect to the compressor contractor through an air handler. You must connect these yellow wires to the Y terminal on your thermostat. There might also be more than one yellow wire.
What do the different color wires mean on a thermostat?
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). You can also refer to the Conductor Color Chart (see Chart 6, thermostat wire).
Is RC and C wire the same?
Hi there! The C and Rc wires are not the same. To install this thermostat you should follow the exact same wiring of the previous thermostat.
What happens if you wire 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.
How many wires should a thermostat have?
The most basic thermostat has 2 wires; usually a red and a white wire. Two wire thermostat wiring is used for furnaces only and usually doesn’t need a “C” or “Common” wire. That’s why we only need two wires: Red wire for power (24h).
What happens if you wire a 2 wire thermostat wrong?
If you get it wrong, the heat will run continuously. Once you have them paired, attach one pair to “24VAC” (R) and the other to “Heat call” (W) on the thermostat. Doesn’t matter which one, since the thermostat just shorts them either way.
