topic Re: Nest + mini-split heat pump in Nest Thermostats

Nest + mini-split heat pump

airhar — Wed, 14 Jan 2026 23:56:38 GMT

Has anyone had any success getting a Nest thermostat to work with an older Fujitsu ductless mini-split heat pump?

Re: Nest + mini-split heat pump

Derickf — Mon, 19 Jan 2026 01:15:54 GMT

Thank you for posting in the community. I understand you are looking for confirmation if the Nest Thermostats are compatible with a Fujitsu ductless mini-split heat pump. I'm happy to assist.

To gather the necessary information, please answer the following questions:

Which Nest Thermostat model would you like to check for compatibility? The following article might be helpful: How to tell which Nest thermostat you have.
Could you please share a picture of your current thermostat wiring?
Could you please provide me with the specific model of your HVAC system?

I'll be waiting for your reply.

Best regards,

Derick.

Re: Nest + mini-split heat pump

airhar — Mon, 19 Jan 2026 17:57:50 GMT

We have not yet committed to a particular model...we'd be willing to purchase whichever model is compatible.

Re: Nest + mini-split heat pump

Derickf — Wed, 21 Jan 2026 06:12:21 GMT

Hi there!

Thanks for your reply. I appreciate your interest in the Nest Thermostat for your Fujitsu ductless mini-split. To provide you with the most accurate compatibility information before you commit to a model, please reply with the following details:

Do you currently use a handheld remote or a wall-mounted controller to operate the unit?
What is the specific model number of your Fujitsu unit?

I'll be waiting for your reply.

Best regards,

Derick.

Re: Nest + mini-split heat pump

airhar — Wed, 21 Jan 2026 19:22:27 GMT

The indoor unit is a AUU18RCLX ceiling cassette. The outdoor unit is a AOU18RLX

Re: Nest + mini-split heat pump

Derickf — Thu, 22 Jan 2026 07:02:27 GMT

Hi there!

Thanks for your reply. I appreciate you sharing the model number of your HVAC system. After reviewing the specifications for your Fujitsu AUU18RCLX ceiling cassette and AOU18RLX outdoor unit, I can confirm that directly connecting a Nest Thermostat to a Fujitsu mini-split is not a standard installation because these systems use different communication voltages. To ensure your system is compatible and to avoid damaging your equipment, I recommend contacting a local HVAC technician who specializes in mini-split systems. They can determine if there is a specific way to bridge the connection between the Nest Thermostat and the Fujitsu unit.

Please let me know if you have any other questions.

Best regards,

Derick.