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-   -   Heat Pump A/C unit not pumping cold air, but fan is running (https://www.askmehelpdesk.com/showthread.php?t=465226)

  • Apr 17, 2010, 10:12 AM
    mohonrim
    Heat Pump A/C unit not pumping cold air, but fan is running
    Hello everyone, first time poster so please bare with me.

    We have 2 units, the main floor unit stopped working this week. By "stop working" I mean that the unit will not blow cold air. The fan appears to be blowing because air is coming out of the vents and the air is room temperature. We turned the system off for a couple of days, thinking it may be frozen. However, this did not work.

    We contacted a service company and he came out yesterday afternoon. I was with him as he inspected everything. First he found that the air filter needed to be replaced. His first assumption was that this had caused the system to lock up or something along those lines. Thus, the system was not able to pull air through to cool, causing the system to go into a lockdown mode that shut itself off automatically.

    Then, I left him alone for another 30-45 minutes. He then returned to say that the TXV valve was bad and would need to be replaced. In addition, the freon would need to be flushed and replaced, and the filter that's located near the TXV valve would need to be replaced at the same time. All for $1200-1500 depending on if I bought the maintenance plan or not.

    So, my question is, does this sound right? How can I verify his findings? Can I do this fix myself? We don't have enough money to do this right now, as I've been laid off for over 5 months and only my wife is supporting us.

    Any help or advice is greatly appreciated. Thank you!

    --
    Shane

    This is a Lennox system, 2002, installed in 2003.
  • Apr 17, 2010, 10:18 AM
    Joshdta

    I see no reason the freon would need to be replaced, inless the compressor burnt out. Are you trying to run your heatpump in heat mode or ac?
  • Apr 17, 2010, 10:19 AM
    mohonrim
    Quote:

    Originally Posted by Joshdta View Post
    i see no reason the freon would need to be replaced, inless the compressor burnt out. Are you trying to run your heatpump in heat mode or ac?

    Ac mode. He made no mention of needing to replace the compressor.
  • Apr 17, 2010, 10:25 AM
    Joshdta

    Turn your ac on, let it run for 5 minutes or so. Go outside and see if the fan is running, Feel the air coming from the top of the unit it should be warm. Feel the copper lines going into the unit. The small line should be warm, not hot. And the big cooper line shoud be cold and sweeting. If after 5-10 minutes if
    The outdoor unit will not come on. You can take the pannel off where the electric goes into the unit. There will be a defrost board in there and it should have a flashing red led fault code light.
  • Apr 17, 2010, 10:40 AM
    mohonrim

    Thank you for your response.

    The air is still blowing through the vents, but as before, just at room temperature.

    The outside unit is not running at all, so I took off the cover as instructed. Both LEDs are flashing and based on the board instructions, that means it's "Operating Normally". I checked both of the copper lines, and both the small and the large lines were just normal, i.e. not hot or cold/sweating.

    So, what next? Thank you so much for your help.
  • Apr 17, 2010, 10:47 AM
    Joshdta

    There is a 5 min time delay on the outdoor unit after your indoor fan comes on. So make sure you have waited for that to cycle out. If you are sure the 5 minutes have passed. You can check for 24 volts, or you can push in the contactor to see if the unit will start manualy. Do you have a volt meter? Is there a set of pins on the defrost board that says test?
  • Apr 17, 2010, 11:11 AM
    mohonrim

    Ok. It's still not running and no change on the lines.

    I do see a test pin. (circled in red in this picture - http://www.shanejordan.net/test.jpg

    Which wire do I put there? Reading the schematic, it appears that the connector is the black square box sitting at the top of this section, or in other words the third unit from the left. Would I take that black wire and connect it to the test pins?
    http://www.shanejordan.net/board.jpg

    I don't have a volt meter, but can get one.
  • Apr 17, 2010, 11:16 AM
    Joshdta

    From the looks of your picture, the bottom picture, the black contactor on the far right that has the main 240 volt wire going to it. It apears to be pulled in like it is supposed to. There for you have no power to this unit. Check the breaker inside the house and the disconnect outside by the unit if so equipped.
  • Apr 17, 2010, 11:31 AM
    mohonrim

    Ah, okay. Well, no luck with the breakers. Nothing was flipped, but I flipped them anyway and nothing happened. There is a box next to the unit where it appears the power runs through, but it's a no-fuse breaker. Not sure what I can do there.

    Any other ideas?
  • Apr 17, 2010, 11:35 AM
    Joshdta

    The tech you had out may have put that outside disconnect in upside down to kill power to the outdoor unit, check to see if it pulls out real easy, if so turn it over and plug back in. if still no power you will need to get your hands on a volt meter and check to see if you have 220 volts where the power wire goes to that contactor inside the unit. The breaker inside the house would have probably been a 30 amp double pole
  • Apr 17, 2010, 02:10 PM
    mohonrim

    You were right about the tech switching it upside down. So, it definitely turned on after that was corrected. However, the fan wasn't spinning and the small copper line coming in was HOT. I'm afraid that I'm not going to like your next response. :-)
  • Apr 17, 2010, 02:48 PM
    Joshdta

    Sounds like you may have a bad fan motor, or start capacitor. With the power off, can you stick something in and see if the fan will spin by hand? If it does you can turn the power back on and try to spin it to get it started. If it starts then it is probably the capacitor if it does not start it is the motor. The only other thing it could be is if your unit is stuck in defrost mode the fan will not spin either.
  • Apr 17, 2010, 08:02 PM
    mohonrim

    Ok, it started! Thank you! But now I have to buy a capacitor and replace it, correct? I'm sure that will be a lot less expensive. And I can do that myself?Just turn off the power, etc.
  • Apr 18, 2010, 05:49 AM
    Joshdta

    The capacitor is the big gray 3 pronged thing far left of your bottom picture. Turn off the 220 power at the disconect. Take a srew driver and short out the 3 prongs. A capacitor will hold a small charge if not shorted out. Losen the capacitor and write down what wires are where. You will have a herm block, fan block , and c block c for common.
    Take the capacitor to a heating and ac store they will test it for you to see if it is good or not. Should cost $25 to $40 depending on the size of it. You could get just a small 5 uf fan capacitor, for around $7 but then you would have to do some rewireing

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