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Problem with a Nest thermostat

Discussion in 'Residential' started by ISOTHERMAL, Feb 19, 2013.

  1. ISOTHERMAL

    ISOTHERMAL senior member

    Messages:
    32,149
    Location:
    Green Acres
    Last summer I installed a customer supplied Nest thermostat.

    It is on a split system Trane heat pump.

    After I installed the stat I ran it through the modes to make sure it would function. It seemed to work fine.

    No problems with heat or cool until this morning.

    Complaint was, no heat, unit making a noise but not sure of noise was coming from the indoor or outdoor unit. also the blower was not blowing.

    I arrive to find the outdoor unit running, vapor line covered in frost.

    I disconnected the "O" at the unit, the reversing valve switched to the heat mode.

    About this time the homeowner came outside, says "I have the thermostat turned off, the utdoor unit keeps running, no blower"

    Sure enough the stat was turned off.

    I removed the stat from the sub base, still had a signal to the compressor and reversing valve.
    I figured there must be a short in the stat wire....Nope
    The only way to get rid of the 24vlt signal was to disconnect the wires from the stat.

    Didn;t matter if the unit was set to heat or cool, the unit would run in cooling mode.

    I ended up reinstalling the old thermostat so they could have heat.

    Anyone else have a Nest thermostat go bad?
  2. Tap

    Tap HoWdY!

    Messages:
    7,467
    Location:
    SOUTH KOREA!
    You have a bad base. Your not the first.
  3. ISOTHERMAL

    ISOTHERMAL senior member

    Messages:
    32,149
    Location:
    Green Acres
    yes the sub base is bad

    I just have not heard of anyone having any problems with them
  4. Tap

    Tap HoWdY!

    Messages:
    7,467
    Location:
    SOUTH KOREA!
    Our installer had a similar issue to yours. I only know second hand.
  5. gusherb94

    gusherb94 Machine Whisperer

    Messages:
    145
    Location:
    Northwest IN/Chicago
    I got rid of my Nest before it could get a chance to go bad. They switch silently so they must use triac's.
    Wonder if Nest also takes after Apple in how they handle warranty claims.
  6. CincyHVAC

    CincyHVAC Hoptimus Prime, Master of Beer-Fu

    Messages:
    45,876
    Location:
    Ohio's Southern Shoreline
    Howdy, Gus. Long time no see....

    Sent from my mind using the Telepathy Pro App.
  7. gusherb94

    gusherb94 Machine Whisperer

    Messages:
    145
    Location:
    Northwest IN/Chicago

    Hi. back from a looooong nap.
  8. CincyHVAC

    CincyHVAC Hoptimus Prime, Master of Beer-Fu

    Messages:
    45,876
    Location:
    Ohio's Southern Shoreline
    Back to the topic....


    I understand Nest is aware of the problem with the sub base issue and are workin to correct it

    Sent from my mind using the Telepathy Pro App.
  9. gusherb94

    gusherb94 Machine Whisperer

    Messages:
    145
    Location:
    Northwest IN/Chicago
    That kinda thing doesn't fly with me. I like a product to work BEFORE it hits the shelves. Kinda remembering something silly about the sub base when I had one for a short period of time last year...
  10. CincyHVAC

    CincyHVAC Hoptimus Prime, Master of Beer-Fu

    Messages:
    45,876
    Location:
    Ohio's Southern Shoreline
    I like 'em to work as well. It's an imperfect world. Some engineer screwed the pooch on this one....

    Sent from my mind using the Telepathy Pro App.
  11. flange

    flange I can't make u do it, I can only make u wish u had

    common issue with sub bases, not just nest. newer electronicals arent always as robust as they need to be, especially if made in a place that no understand the nature of hvac equipment.
  12. Texas-Tech

    Texas-Tech stranger*

    Messages:
    9,030
    Location:
    duhh
    Most stats don't sell for 250$ either.
  13. flange

    flange I can't make u do it, I can only make u wish u had

    have seen plenty of high dollar, commercial honeywell stats with the same problems, in fact, when I wokred for them, we used to carry spare sub bases in all of the trucks....
  14. Catpower

    Catpower The Crowd Pleaser

    Messages:
    15,670
    Location:
    in the Cabana

    Could those have been 7300"s?

    Sorriest stat ever made
  15. flange

    flange I can't make u do it, I can only make u wish u had

    ummmmm, coooooouuld beeeeeee.........
  16. Dowadudda

    Dowadudda Staff Member

    Messages:
    4,010
    Location:
    Motor Room
    god those were Peices Of $hit.
  17. Snoring Beagle

    Snoring Beagle Need Little - Want Less - Love More

    Messages:
    10,277

    +1

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