What causes no power to Rh wire?

To fix an E74 error or no power to the Rh wire error on your Nest thermostat, check for loose connections and fix them. If that does not work, clean out the drain pipes and check if the condensate pump associated with your HVAC is clogged.

Why is my Nest thermostat reading no power?





A “No power” alert can be caused by the following: The thermostat wiring is incorrect. Your thermostat is connected to a system that requires a C or common wire, but that wire isn’t connected. Some systems, including heat-only, cool-only, zone-controlled, and heat pump systems, require a C wire or Nest Power Connector.

How do you reset Nest thermostat when moving out?

To do that, follow these instructions:

  1. Press the thermostat ring to open the Quick View menu.
  2. Choose Settings (the gear icon)
  3. Turn the ring until Reset is highlighted then press to select.
  4. Choose the All Settings option to perform a full reset.

How do I reconnect my Nest to power?

To reset your Nest, go to Settings > Reset > Network > Reset > Confirm. Now, go to Settings > Network and follow the onscreen directions to reconnect your Wi-Fi with your thermostat. This step can take a while, but it usually solves any lingering problems.

What is the Rh wire for?





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.

Should Nest be connected to RC or RH?

The Nest Thermostat E only has an R connector, which is typically where an R wire would go. If you have separate heating and air conditioning systems, you might have separate Rh and Rc wires that come out of the wall and are connected to your system.

How can I tell if my Nest is getting power?

In the Device Information > Power section of Settings, you’ll find the Battery section. Here you’ll find Voc, Vin, and lin readings of your Nest thermostat. These indicate the flow of electricity through your wiring. Check that these readings don’t go below a certain level.

How do I reconnect my Nest thermostat?

Nest Thermostat E or Nest Learning Thermostat

  1. Reset the network. On your thermostat, open the Quick View menu. Select Settings. …
  2. Reconnect your thermostat to Wi-Fi. On your thermostat, open the Quick View menu. Select Settings. …
  3. Reconnect your thermostat to the app. On your thermostat, open the Quick View menu. Select Settings.


What do I do if my Nest doesn’t turn on?

If your Nest Thermostat is off and won’t turn on, take the thermostat off the base and charge it using a USB cable plugged into a wall charger or a computer. PLEASE NOTE: Do not try to restart your thermostat while it’s still connected to a computer for charging.

Are R and RH wires the same?

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.

Does red wire go to RC or RH?



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.

What is the R wire on a Nest thermostat?

The R wire is the power wire for your heating and cooling system. If you only have one R wire (no Rh or Rc), you can connect your R wire to either Rc or Rh on the Nest thermostat.

How do I fix no power to Rc wire?

The E73 error on your Nest thermostat indicates that there is no power detected to the Rc wire. To fix this error, check your wiring, air filter, drain tubes/drip pans, and HVAC fuse and ensure that all of them are working correctly.

Do I need a jumper from RC to RH?

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. The only time this jumper would be removed is if the heating and cooling systems have their own transformer.

What’s 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.)

Is C wire the same as RC wire?

The C and Rc wires are not the same. To install this thermostat you should follow the exact same wiring of the previous thermostat.