How to disable G-wire when starting W1 or W2

[DidPanas]

Hi all, I have a question, is it possible to disable the forced start of the fan, when starting the heating W1 or W2. Now, when starting the heating, the thermostat Nest in addition to W1 turns on G and this leads to the fact that the fan runs on the third speed, instead of the second and creates more noise, especially it is felt at night. I found in the manual that there is an option to turn off the fan, but it is not available to me, is this only for PRO users?

[luciaaa · Accepted solution]

Hi, @DidPanas!

Thank you for reaching out to the community. I understand that your fan turns on every time the heater does, and that it runs at third speed instead of second. I understand the noise results are quite annoying, especially at night. I'd be happy to help you with your request to turn off the fan.

To provide you with the best assistance, please answer the following questions:

• What type of thermostat do you have?
• Do you have a conventional system or heat pump system?
• Conventional System: Typically consists of two pieces of equipment (furnace and AC).
• Heat Pump: Handles both heating and cooling with a single unit.
• Besides the fan running at third speed, do you have any strange behavior with your system? 

To change the speed of the fan or directly turn it off, you can do it from the thermostat itself or from the Google Home app or Nest app. You can refer to the following article to find instructions: Fan control with a Nest thermostat. 

Please let me know how it goes.

Best regards,

Ana

[DidPanas]

Hi, Ana @luciaaa 

I have a Nest Learning 3 gen thermostat.

I have a rather old heating system, electric furnace Nortron 21B20, which works as W1 or W2 (i.e. has two heating stages) and in summer, can only work as ventilation (G). When I connected all the wires as G->G, W1->W1, W2->W2 and R->R, during the W1 heating test, the thermostat showed that it will run as (G,W1), although I only want it to run as W1. I have no option in the settings to disable ventilation when setting W1, although the manual has this option.

Merci et bonne journée,

Stanislav

[luciaaa]

Hi, @DidPanas!

Thank you for your prompt response. I appreciate the detailed information you shared about your HVAC system and thermostat. I'm happy to assist you further.

Changing the configuration through the setup option usually requires a Nest Pro technician for security purposes and to prevent damage to your HVAC system. However, since we're only disabling the fan, calling a technician may not be necessary.

On the Nest thermostat, navigate to Settings > Equipment > Continue > Continue > Pro Setup. Select either the single-fuel or dual-fuel system option, depending on your setup. Then, on the diagram, select W1, scroll down to Fan, select "activate," and then select "continue." Next, go back to the diagram, choose W2, and confirm the fan is disabled for that option.

Please let me know how it goes.

Best regards, 

Ana

[DidPanas]

Allô, @luciaaa 

Thank you for your reply. Unfortunately, this cannot solve my problem, because when selecting the type of heating furnace as electric, the option with fan off/on is not available. The only way I have found is to change the furnace to a gas, then the option with fan is available. This is a very strange solution, why is it only available for the boiler type with gas?
Anyway, I changed the settings yesterday, selecting boiler type with gas and with fan disabled and it works fine, finally the fan does not run on third speed and it's fine!

Still I have a question : is there any way I can set the electric boiler to work with the fan disabled? If not, can I leave the boiler type as gas boiler in my case? Will this not change the logic of the thermostat itself?

Thanks!

[luciaaa]

Hi, @DidPanas!

Thank you for your prompt response. I sincerely apologize that the option to turn off the fan is not appearing when you select "electric" as the heating source.

To ensure the correct configuration, I recommend performing a factory reset on the Nest thermostat and then setting it up again. Please refer to this article for instructions: How to set up your Nest thermostat.

During the setup process:

• Do not select "already installed." Select "continue."
• Choose "electric" as the heating source.
• You will see the option to "Turn on the fan with heating." Select "No." The fan shouldn’t turn on with the heating system.

If you don't see this option, the fan may be set to turn on by default when you request heating with your thermostat.

For advanced configuration options, you can contact a Nest Pro technician to see if they can adjust the settings in your Nest Learning Thermostat 3rd generation.

Please let me know how it goes.

Best regards, 

Ana