R , Rh , and Rc are all the same, but not. In general terms, the R terminal is where you connect the signal voltage source. In low voltage controlled systems, there will be a step down transformer that provides the power to the control circuitry.
Is r the same as Rh?
In a thermostat, the R wire is responsible for powering the entire HVAC system (through a transformer). 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.
Is the R wire the same as the RH wire?
Some units don’t have an RH wire, but instead, they have an R wire. An R wire is similar to either the RC or the RH, so if you don’t have an RH wire, the R wire will be in place to control the heating system.
Does R wire go to RH or RC?
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.
What is the R terminal on a thermostat?
R – The R terminal is the power for the thermostat. This comes from the transformer usually located in the air handler for split systems but you may find the transformer in the condensing unit.
What does RH stand for on a thermostat?
Rh stands for Red-Heat and Rc stands for Red-Cool. If you only have a single red wire the jumper between Rh and Rc are required for some heating and cooling hybrid systems depending on your thermostat. Yellow/Y is the AC compressor. White/W is the Heating element. Green/G runs the fan.
What is RC or 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.)
What is the Rh wire for?
The Rh wire is the power input to the heating system of your air conditioning. If the connection is not established, your air conditioning will stop working.
Where does Rh wire go on thermostat?
The Rh wire connects to your heating system as opposed to your cooling system. This wire may be red without an H attached to it, depending on if you have a dual transformer setup. The Rh wire connects to the RH terminal on your thermostat.
Do I need a jumper from R to RC?
If you have a wire in the R terminal, and another wire (not a jumper) in the RC terminal, you will not need to connect the R and RC terminals. See our Basic Wiring article for more info here.
Why is there a jumper between R and RC on this thermostat?
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.
Why is there a jumper from R to RC?
Is there a separate wire on Rc and Rh or is it just a jumper wire? You put the R to the Rh (heat) and Rc to Rc (cooling) those are both + 24V AC so you must have a transformer in the AC unit and another in the heating unit.
What is the Rh wire on the Nest thermostat?
The Rh wire is a kind of red wire that provides electric power from the transformer 24×7. Unlike your cooling system, the Rh wire connects to your heating system. If you have a dual transformer setup, this wire may be red without an “H” linked to it. The Rh wire connects to the RH terminal on your Nest thermostat.
