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  1. #1



    I am an unhappy owner of a Water Furnace geo unit. It has been running for about a year, and we've had many problems.

    I will try to spare the details, and go straight to my current problem.

    There is something wrong with the electrical connection. The loop compressor is trying to start, but it just buzzes for about 3 seconds (house lights dim) and gives up. We had this problem last winter when the unit was running for just one month. I had the installer out several times and together we finally pinned the problem down to a faulty breaker.

    After about a year, the problem is back. The loop compressor isn't working, we're on expensive electric aux heat tonight, and tomorrow morning I'm heading out to the electrical dealer to get new breakers. Add $90 more to the energy costs!!

    There are some things that don't quite add up. First, there is a 90A circuit and a 60A circuit. The compressor is on the 60A circuit. The 90A circuit is wired for 100A because a 90A breaker is not available. We have a 200A Cutler Hammer BR panel dedicated for the geo. The thing that doesn't make sense is that the problem was solved by replacing the 100A breaker (the aux heat), and NOT the 60A breaker (the compressor). It should be the reverse.

    Another strange thing is that the 100A breaker tests OK. But it is 100% reproducable to recreate the behavior by restoring the original breaker. Now I have two failed breakers apparently.

    And the problem seems to be brought on by heavy use of aux heat. Over the last month, it was very cold. The geo has run 24 hrs since early December.

    [In fact, we were so uncomfortable last year with the fan on high that we put in 50K btu more heat via a gas boiler/radiant heat in our favorite rooms.]

    According to the installer, the compressor checks out fine.

    Are there ways the breaker can fail by getting too much heat through the wiring when aux heat is running a lot? Any suggestions on tests to further isolate the problem?


  2. #2
    Join Date
    Feb 2003
    has anyone done accurate voltage measurements on the incomming line side of the panel simulanteous with the voltage at the load side of the breaker & at the aux heaters & at the compressor?
    bad connectors into the panel, at the meter, ...

    have the connections TORQUED for any circuit larger than 70a.

    front of breaker getting hot?
    have the breakers interrupted faults several times?

    kw load of aux heat
    wire type, size and length
    how wire installed

  3. #3
    Thanks for the response.

    Voltage readings were taken, but not simultaneously. Also I don't think they explicitly checked voltage at the compressor and aux heat elements.

    Tonight I took the breakers out to inspect them. They were slightly warm but certainly not hot. The connections were cranked down pretty good. There are no indications of intermittent connections, sparks, etc. Is there a specific torque tool required?

    The breakers have not tripped, not even once.

    The wire is #4 for the 100A and #8 for the 60A. They run about 18 feet total from panel, up to ceiling, down to unit and into connectors. Both wire runs are in conduit.

    The furnace is heating the house, so enough power is going through both circuits to run the aux heat and blower.

    I will ask the installer to take more measurements inside the unit.

  4. #4
    Join Date
    Dec 2004
    South Central Kansas
    Sounds like "almost" tripping a breaker. It could be a bad start or run capacitor...if that's the case you could only check it with an expensive meter and experience knowing what to check.

  5. #5
    Join Date
    Apr 2003
    sounds like a bad start up... try a hard start kit? Check the capacitors.... can't see a breaker causing you problems something is hitting hard on start up it sounds like and that just wears on the breaker.. Check to see if your model has a start kit upgrade. Some came out without them but they found they needed them. Is the compressor slugging on start up? Another thing to check... the incoming wire is it aluminum? Is it still tight in the box? If your not good with wiring don't get electricuted.

    [Edited by airconman on 02-05-2005 at 03:49 AM]

  6. #6
    Join Date
    Jul 2004
    Fort Lauderdale, FL
    I have been working on a system with a similar problem in Massachusetts. The system was grossly overcharged. The breaker went once on it. It now has the correct charge and a hard start kit and it has been fine since like mid December. I don't know why someone would put a geo heat pump in New England. This poor customer runs off of electric backup most of the season anyway.
    How much is it an hour?

  7. #7
    Join Date
    Feb 2003
    so, someone put in wire rated at 90C, rather than 60C. not good for hard starting equipment!

  8. #8
    I replaced the 60A breaker today, and the unit is working again. Last night I cycled the power a few times which didn't help.

    I will ask the furnace installer about the hard start kit. That part makes a lot of sense. The unit has always made a noticable ring tone every time the compressor gets going. The cooling cycle last summer was so loud that I had the installer come out. They padded all the piping to dampen vibration noise.

    One problem with the installer is they do not provide electrical. The electrician was not exactly clear on the requirements. All that came with the unit was power requirements. So it has been a case of each contractor pointing at each other.

    The wire is copper. How would aluminum wiring help?

  9. #9
    Join Date
    Oct 2003
    west chester pa
    sounds like your system is overcharged call and pay for another contractor to check system call water furnace for a recomended contractor in your area. or post location and maybe someone off of this site could help.

  10. #10
    Join Date
    May 2002
    #2 wire for 100a breaker/#6 for 60a breaker (I always use copper) but that's just how I do it. James

  11. #11
    Your waterfurnace has a 10 year parts warranty on it. By you the homeowner doing repairs your self are voiding that warranty. Please go to this site here fill the card and get some help before you get into things way over your head and void the entire warranty. The mfg will help you. also i have enclosed here the homeowner papers of which you should have in hand. here they are.

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