Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Heating & Air Conditioning (https://www.askmehelpdesk.com/forumdisplay.php?f=150)
-   -   A/C blower fan won't stop when thermostat is off (https://www.askmehelpdesk.com/showthread.php?t=136360)

  • Oct 2, 2007, 02:37 PM
    gbwillner
    A/C blower fan won't stop when thermostat is off
    Sorry for the separate thread...
    I had a bad blower fan up in the attic. I ended up taking apart the blower and seeing that the fan was completely disgusting and rusted through. After a very hot weekend without A/C, I took the fan to a parts wholesaler and got a new one. It was harder than I thought to put the motor through the new fan, but after a couple of hours the fan was back in one piece. I set up the system and turned the power back on... The fan was working great...
    Then I turned the thermostat off to turn off the fan... only the fan kept going. I realized the motor had just slower down. The motor is a 3-speed. I shut off the power at the fuse box, and of course this shut down the fan.
    I'm very confident I rigged the fan the same way it was before- I only separated three cables from the motor, and then put them back (red to blue, black to black, and yellow to yellow). What happened?? Please help!
  • Oct 2, 2007, 05:14 PM
    J Costa
    Sounds like it would be your relay is stuck. What made you take the fan apart in the first place? What I mean is was there a problem before that made you look at the fan?
  • Oct 2, 2007, 05:25 PM
    gbwillner
    Quote:

    Originally Posted by J Costa
    sounds like it would be your relay is stuck. What made you take the fan apart in the first place? What I mean is was there a problem before that made you look at the fan?


    Thanks for the response.

    I took the system apart because the blower fan became disconnected from the motor- it was rusted through. I replaced the fan, and put the blower back together.

    Actually, now I have an additional problem. The condenser, compressor, capacitors, and blower all work. However, the air that comes out is not very cold. I noticed that the freon "cold" line coming into the house is not very cold either, although the "hot" one is. There is condensation on the condenser and air coming out of all the vents. Any ideas??

    Thanks
  • Oct 2, 2007, 05:59 PM
    J Costa
    You are probably low on refridgerant if the low side line, the fat line is not cold and has no condensation on the line outside and you say the compressor is working that is probably your problem.
  • Oct 2, 2007, 06:06 PM
    T-Top
    You said the blower slowed down when you shut it off at the thermostat. If its electric strip heat you may have a heat sequencer stuck. The blower relay will energize the high speed for cooling when the relay drops out the low speed is controlled by the heat sequencer. You said the air was not that cold in a/c mode sounds like a strip may be stuck on to me.
  • Oct 2, 2007, 06:10 PM
    gbwillner
    Quote:

    Originally Posted by T-Top
    You said the blower slowed down when you shut it off at the thermostat. If its electric strip heat you may have a heat sequencer stuck. the blower relay will energize the high speed for cooling when the relay drops out the low speed is controlled by the heat sequencer. you said the air was not that cold in a/c mode sounds like a strip may be stuck on to me.


    Thanks!
    How do I fix this?
  • Oct 2, 2007, 06:22 PM
    T-Top
    If it's a bad sequencer you can take the red blower wire off the sequencer and tape it off. (turn power off first!). If you have a heat strip that hooks up at the same point you need to disconnect it to and tape off. This will get you going until you can get a new part. It's a common part and not expensive. I hope it works out for you.
  • Oct 2, 2007, 08:00 PM
    gbwillner
    Quote:

    Originally Posted by T-Top
    If its a bad sequencer you can take the red blower wire off the sequencer and tape it off. (turn power off first!). If you have a heat strip that hooks up at the same point you need to disconnect it to and tape off. This will get you going until you can get a new part. its a common part and not expensive. I hope it works out for you.


    Thanks!!

    I ran the AC (even though it wasn't cold) just to de-humidify the house. When I went back up to the attic (where the blower/furnace is) I smelled something burning. I touched the back plate of the heating elements and noticed they were really hot.

    I guess the problem was the blower and furnace were both permanently "on" for whatever reason. I took the leads off the heating coils and the A/C is now running better than ever.

    If anyone knows how to replace this part (or knows a good resource) plase let me know.

    Thanks again!

  • All times are GMT -7. The time now is 04:13 PM.