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Home cooling/condenser problem

  1. Aug 1, 2010 #1

    EnumaElish

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    The heater/cooling system (HVAC) at home has a condenser unit. It's a small electric motor sitting atop a shoebox-sized metal container which holds the water dripping from the "fan unit" (I don't have a better technical term to describe the main unit that houses the fan). There is also a thin hose that rises from the water box and goes into the ceiling, I have no idea where, or why.

    My question is: do I need to empty the water accumulating inside the box? I never emptied it for almost 10 years, and it did not present a problem. Lately, the A/C has stopped working and has been difficult to restart, and I'm guessing that the reason has something to do with the condenser.

    FWIW, the HVAC is part of a multi-home system -- there is a "plant" somewhere that needs to be operating for the HVAC to work.
     
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  3. Aug 1, 2010 #2

    dlgoff

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    The motor on the box/reservoir is probably for running a pump to remove the condensate. It probably goes to a drain. If the pump stops working, you would start to see the reservoir overflowing. I don't believe this problem would cause the unit to not start however.
     
  4. Aug 1, 2010 #3

    russ_watters

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    Oy.

    A split system home a/c unit consists of two parts:

    The condensing unit is a (usually) cylindrical heat exchanger with a fan at the top and a compressor to compress the refrigerant.

    The air handling unit is the box with a fan that sits inside your house and circulates air through your house. It contains an evaporator coil, which is where the refrigerant cools the air by evaporating from a cold liquid to a warm gas.

    When the evaporator cools the air, some water will condense out of the air. The evaporator contains a drain pan which is connected to a drain hose and drains this condensate from the drain pan where it goes to a shoebox-sized pump mounted to the side of the air handling unit. When the tank on the pump fills, the pump pumps the condensate to the nearest drain.

    So no, what you are describing is a condensate pump with a tank on it and it will empty itself periodically as long as it isn't broken.

    http://www.plumbersurplus.com/Cat/Condensate-Pumps/284/List [Broken]
    That's more likely a fan or thermostat problem, but if you live in an apartment building and don't own your system, it isn't your problem anyway: just call your management office and they'll fix it.
    Do you live in a large apartment building? If so, there may be a chilled water plant on the roof, in which case my description above is off a bit. In which case the parts/heat flow are:

    Cooling tower makes cool water to cool the condenser in the chiller.
    Chiller contains the evaporator and condenser and makes cold water.
    Air handling unit (aka "fan coil unit") in your apartment that passes the cold water through a heat exchanger to make cold air.

    It would be pretty unusual for you to own your fan coil unit if you live in an apartment building with a central chilled/hot water plant.

    Could you answer these two questions, please:
    The air handling unit or coil that makes the cold air has two pipes (and one nylon tube, probably) connected to it. Are they the same size or is one larger than the other?
    See if you can find a sticker on your a/c unit with a model number or name. Could you tell me what they are?
     
    Last edited by a moderator: May 4, 2017
  5. Aug 1, 2010 #4

    EnumaElish

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    Thanks, dlgoff!

    Thanks, russ!!!
    You're right, I don't.

    They are the same size.
    "FHP," manufactured by Harrow Products, "SE032-1."

    [quotes fixed - russ]
     
    Last edited by a moderator: Aug 1, 2010
  6. Aug 1, 2010 #5

    russ_watters

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    Ok, does sound like a chilled water system/fan coil unit - so it's the second system I described. In a refrigerant based system, the two pipes are different sizes because one contains a liquid and the other a gas.

    I've never heard of that manufacturer and don't get any hits on a google. So at this point, if you're having problems, just call your maintenance/management service.
     
  7. Aug 1, 2010 #6

    edward

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    Most A/C units that utilize a condensate pump have an overflow switch. The switch will open the control circuit to the A/C if the water in the condensate container gets above a predetermined point.

    I had a big mess with one of these things a few years back. It turned out that all kinds of yucky junk was growing in the condensate container and lines blocking the flow.

    EnumaElish:

    If you have free maintenance service by all means call them. Sometimes the condensate pumps plug into an electrical outlet near the unit. Is it plugged in?
     
  8. Aug 1, 2010 #7

    russ_watters

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    That's a good point. The drain pan in the fan coil unit may also have a high-limit switch. But....
    ....the drain pan of my department's air conditioner at work did not have a high limit switch. Woulda been nice when the condensate piping got clogged with yucky junk a few weeks ago...
     
  9. Aug 2, 2010 #8

    dlgoff

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    Yea, Mine either. Once I wished it had. There's a gravity drain line in the bottom of my ACs tray. Yep, it clogged up. Since the it's is in a closet area, it got really wet before I discovered it.
     
  10. Aug 2, 2010 #9

    Gokul43201

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    It shouldn't be too hard to look in the drain pan and see if there is a level switch (and if the condensate has accumulated to the level of the switch).
     
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