(6 Easy Ways) – How to Fix Nest Error E195?

Are you here because you just received an error message indicating E-195 error- No power to R detected? To solve this error, you first need to rule out the main cause behind it, for which you need to follow a proper step-by-step guide.

So, what does nest error E195 mean?

The Nest error E195 indicates that you don’t have any power supply to the R wire. The R wire is responsible for powering your HVAC system. So, whenever there is such an issue, your heating, and cooling system will stop working or even get damaged. So, start with checking the wires and ensuring the drains are clean.

Keep reading to understand all the hacks to fix Nest E195 error quickly.

how to fix nest error e195

How to fix Nest error E195?

To fix your Nest error E195, you first need to check your system’s power. If the power is available, head on to check individual equipment and connections like float switch, drain line, thermostat wiring, and R wire.

Here are the steps to fix your Nest E195 error:

1. Check the power of your system

The first hack to resolve error E195 is to ensure your device is receiving adequate power to function. If not, then turn the switch on.

The switch for the power to your system is usually within the beaker box or the fuse box. You may find either one switch or maybe sometimes two such that for heating and cooling purpose separately. So, ensure they’re on.

If the switch/switches are on, head to the fix below.

2. Connect the R-wire properly

As discussed earlier, error E195 indicates an unidentified R wire. Therefore it’s essential to ensure the proper connection of the R wire to the R connector.

Here are the steps to ensure proper connection of your R wire:

  1. Firstly, turn off the electricity at the breaker to troubleshoot.
  2. Next, remove the R wire from the connection.
  3. Straighten the wire and then re-stripe it ensuring the exposure of around half a centimeter of the wire.
  4. Now, insert the wire into the R connector. Ensure to keep the button down when you release it.
  5. Lastly, turn back the power on and check if the error has gone.

In addition, we observed that users with a transformer could get rid of this problem when they connected the blue wire to the transformer. So, try this hack if you discover any such wire and have a transformer. Finally, you may find this wire connected to some other equipment such as a furnace.

3. Check the wiring of your thermostat

If, even after connecting your R wire all over again, you didn’t get the desired result, try out this fix. But, then, you must ensure your thermostat’s wiring is fine enough to function well.

So, simply remove the thermostat from your wall and inspect the connection carefully. However, if you have installed your thermostat without the C-wire, then follow the steps given below:

  1. Firstly, check if all the wires are connected appropriately to the connector.
  2. Next, ensure that all the wires are exposed up to 6mm.
  3. Lastly, ensure that all the wires are connected properly to the system board.

Also Read: How to fix Nest no power to Rh wire

4. Ensure the float switch isn’t tripped

The next fix is to ensure that your float switch has no internal damages within or isn’t tripped and is functioning well.

The float switch is basically a safety device that prevents any sort of damage to your Nest thermostat. For example, when you turn on your air conditioner, the condensation process occurs; thus, the float switch ensures that the condensation doesn’t go above a certain level.

However, if the condensation overflows, the float switch trip and your thermostat will get defective in no time. Moreover, your Air conditioner will not work well, which may be super annoying for you.

So, if you see your float switch tripped, turn it back on after removing all the clog, and your error E195 will be resolved soon.

5. Check the condensation drain line

After checking the float switch and cleaning it, it’s pretty necessary to check the condensation drain line. If you just turn your float switch on without doing this step, all your hard work will go in vain.

Moreover, another hint for you is your thermostat screen turning black repeatedly with an error message. So, in such a case, you cannot ignore checking the condensation drain line. The dirt may build up the growth of bacteria for whom a dark and warm place is surely pretty suitable to survive.

Moreover, the slime and super leaky pipes may not just damage your thermostat or air conditioner but your ceiling as well.

So, for your ease, you may contact the HVAC technician to resolve this proper as sometimes this problem may get out of your hand.

6. Contact the Nest customer support team

Lastly, if none of the above hacks goes well for you, then the only option is to contact the customer support center and ask for their assistance. Simply explain the problem to them, and they’ll get in touch with you within 24 hours.

They may even send a technician who will find out the main background cause and resolve it in no time.


What is the r wire on a thermostat?

The R wire on a thermostat is the power wire for the heating and cooling system. Depending on the model, it may be one or two on your system. If one, you may connect it to either Rh or Rc on your thermostat.

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The Nest error E195 indicates no power to the R wire. However, it may occur due to multiple causes, including no power to the system and improper wiring. Therefore, to fix this error, you just need to check individual equipment and connections like that float switch, thermostat wiring, and R wire.

In this article, we have written some important hacks that may help you resolve the nest e195 error in no time. However, if it doesn’t, feel free to contact the customer care support team that will assist in every possible way.

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