Nest Learning Thermostat 2nd Generation Base Motherboard Replacement

Written By: Rachael Deptula
  • Comments: 14
Nest Learning Thermostat 2nd Generation Base Motherboard Replacement

Difficulty

Moderate

Steps

7

Time Required

25 - 30 minutes

Introduction

When replacing the base motherboard, removal from the wall is necessary and power to the thermostat must be turned off. The tools required are the blue opening tools, spudger, and a #0 Phillips screwdriver.

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    • Before disassembling your Nest Thermostat, be sure that your HVAC system is powered off.

    • Grasp the display's metal outer ring with your fingers and pull directly away from the wall, leaving the base behind.

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    • Remember to turn off the power to your HVAC system and the thermostat.

    • Disconnect all wires from the grey spring-loaded connectors. This can be done using your fingers.

    HOW do you disconnect the wires? I can't get them out!

    Beverley Brown -

    Same here. It is like the springs are in a stuck position

    Bill Redfield -

    I also can not dis-engage the wires. Feels like the springs are frozen closed.

    Bill Redfield -

    Hold down the button on the end and the wire should be able to slide right out.

    Amber -

    Yes, the button on the end of the wires is stuck in the down position. Tried pushing with my fingers and several smaller tools- they appear to be frozen in the down position.

    Garet Ten Cate -

    If you hold the buttons down while pulling the wires, they'll come right out and the button springs reset.

    Dan -

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    • Remove the two 40mm screws from the base of the thermostat using a #0 Phillips screw driver.

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    • Unsnap the base from the trim plate (if used) using a plastic opening tool.

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    • Turn the base over.

    • Remove the four 6 mm screws from the back of the base using a #0 Phillips screwdriver.

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    • Pry the base mother board open from the side using a plastic opening tool.

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    • The base mother board is only held together by light adhesive.

    • Pry the baseboard from the bottom using the flat end of a spudger.

Conclusion

To reassemble your device, follow these instructions in reverse order.

Author

Rachael Deptula

Member since: 04/09/14

990 Reputation

8 comments

Would like to know where I can get just the base motherboard.

wesbug -

Where can we purchase replacement parts?

brettspradley -

i want the baseboard.. where i can buy? pls help...

john gemora -

Yep, my base unit lasted exactly 8 days, then it shorted out. The furnace repairman said he has seen it a couple of times, the base unit can't handle the current needed by the furnace so it goes poof. Back to Honeywell...

bbolen -

No replacement parts from Nest, my base unit died and I have perfectly working thermostat but am forced to buy a new one cause I can't get the base unit on its own.

Adrian Ma -

I have no clue why people like their thermostats to the degree that they do.. I am both an A/c professional and an Engineer. They use what is called an SCR or silicon controlled rectifier for their switching instead of a tiny relay. An SCR is very sensitive to a spark or voltage spike. Yes the thermostat is pretty cool and has some nice features. It is advanced electronics but using SMC's or Surface Mounted Components?? . Maybe that would work well in a shielded component. But NOT in something that is connected to long external wires. The consumer bought warranty is only one year. I have seen too many issues in the field with their overpriced toys. Not having parts for this Chinese made thermostat? Priceless.

Jon Reid -

Hey Jon, I’m trying to repair my parent’s 2nd Gen Nest. It sends out “heat” and “cool” signal at the same time. Anyway I can replace a component on the motherboard?

Lizik -

Good post. Wish I had read before I got a Nest thermostat. What would you recommend as a good alternative? I hate when you can't replace simple components and parts cheaply and quickly. What the !&&*.

doughboy1338 -