Thermostat, Breaker, unit??

Discussion in 'HVAC Heating & Cooling' started by neterpoo, Jan 20, 2012.

  1. neterpoo

    neterpoo New Member

    Messages:
    8
    Location:
    South Carolina
    We have a gas pack heating unit (runs off of propane). recently, we have noticed it getting really cold inside. When we go to the thermostat we see that it is much colder than what the thermostat is set on (like it will be 60 degrees when it is set on 65) and the unit isn't running. I thought maybe the breaker had tripped but when I checked the breakers, none where tripped. I can cut the breaker off then on again and voila the heat comes on. Is this a breaker problem, unit problem or a thermostat problem?
  2. DonL

    DonL Banned

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    I don't think that it is a Breaker problem. The fact that it restarts could just because you are resetting a Safety Lockout.

    Can you give a Model for the Unit and the thermostat Model ?

    You may get a better answer if you have that info available.
  3. neterpoo

    neterpoo New Member

    Messages:
    8
    Location:
    South Carolina
    thermostat: Robertson Item 9500 (i don't see a model number) unit: International Comfort Products model 0 serial number G072812087
  4. neterpoo

    neterpoo New Member

    Messages:
    8
    Location:
    South Carolina
    there is also something on the unit that says "ARI"
  5. DonL

    DonL Banned

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    Should also have a sticker that says Caution.
  6. neterpoo

    neterpoo New Member

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    8
    Location:
    South Carolina
    I'm sure it does...were the numbers I gave you what you were needing? if not, I can go look again.
  7. DonL

    DonL Banned

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    I would verify that the thermostat is working, and replace its batteries if it has some.

    if your unit is Model 0 , then you need a better one.

    If it is a Thermostat temp error problem, You can raise it 5 degrees to makeup for the difference, Unless it is the anticipator on the Thermostat or maybe the system could have another problem.

    Do Not play with any Gas ! Call a pro, Instead of Blow...
    Last edited: Jan 20, 2012
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    Are there any lights on the heater? Some of them have indicator lights that either come on or off or blink in a particular sequence. Those can tell a lot about what's happening, if you can find the manual (and if they have any in the first place!).

    Most burners have some sort of a sensor that determines if the burner actually comes on when told. That could be dirty or not working, or intermittent. If it doesn't have a pilot light, the ignitor may be spotty in its operation. Watching what's going on during a cycle may lead you to what's going on and pinpoint the problem. It really helps if you can read the user's manual on the theory of operation first, as that would tell you what is supposed to happen and why. I know that's the last thing a lot of people want to hear (read the manual), but it can often help sort out problems. As we used to say in the Army - RTFM!
  9. neterpoo

    neterpoo New Member

    Messages:
    8
    Location:
    South Carolina
    The unit was installed new in 2007...the thermostat was also new. Our home is 100+ years old and this is the first central heating it has ever had. I will look for the manual...I haven't seen any indicator lights.. we have raised the temp 10 to see if that would change anything, still won't come on unless we turn the breaker off and on, replaced the batteries, still no difference. thanks for the help
  10. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    If it has indicator lights, they may be inside - you may need to take an access cover off.

    Often, you can find the manuals for newer units on-line at the manufacturer's website.

    There are lots of things it could be. Also, inside the access cover, they usually have a wiring diagram that shows all of the interlocks. If you're handy along with the manual, you can see where the interlock signal is missing to help diagnose what's going on.
  11. DonL

    DonL Banned

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    A Valid Model Number is what I would look for.

    Then you can find and RTFM...
  12. neterpoo

    neterpoo New Member

    Messages:
    8
    Location:
    South Carolina
    Honestly, it says model 0 or maybe its o....but I will look again when the rain stops and in the light of day. Thanks again!
  13. DonL

    DonL Banned

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    I guess Ford made a Model T so that may be correct.

    I did not find any info using your model, but it must be out there somewhere.

    Maybe a Pro on that brand may stop by and clue us in.


    Good luck on your project.


    P.S. If that is a outside unit, then it may be doing the best that it can do. (or maybe you have a air leak)
    Last edited: Jan 21, 2012
  14. neterpoo

    neterpoo New Member

    Messages:
    8
    Location:
    South Carolina
    I waited for the rain to stop...but it didn't...so I braved the cold rain anyway (something i would usually leave up to my husband but he was working) and here is what I found: there are two large stickers on the side of my Heil unit- the top sticker says International Comfort Products model 0 and mfg# PGF35410k00a1---, the bottom sticker has this same number as the model number
  15. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
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    Location:
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    About the only sure way to evaluate your unit is to watch it to see if it the thermostat is turning it off, or if it is going into a safety mode which locks the system down until reset by turning off the power.
  16. Tom Sawyer

    Tom Sawyer In the Trades

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    Location:
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    Jumper the thermostat terminals, either at the thermostat or the unit itself. If it runs then the thermostat is bad but I doubt that's the problem. I suspect that the thermal disc, high limit switch is locking it out. Either way though, this is not really a home owner fixable thing so call someone that knows what they are doing.
  17. neterpoo

    neterpoo New Member

    Messages:
    8
    Location:
    South Carolina
    should this be an expensive fix? if the thermal disc, high limit switch is locking it out?
  18. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
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    Location:
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    No easy way to tell. Often, those interlocks themselves are fairly inexpensive, but figuring out what is wrong takes both time and skill unless you shotgun it and haphazardly replace parts. Course, if they're cheap enough, it may be cheaper than a service call, but probably not. But, keep in mind that the thing that is preventing it from running right might be working properly, and something is causing the system to be out of whack and the sensor is just doing it's job. Try to find the manual, review the theory of operation, and see if you can isolate it. If not, then it's probably cheaper to pay someone.
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