Lennox Heat Pump Contactor Problem

Reply

  #1  
Old 05-04-01, 07:02 PM
Member
Thread Starter
Join Date: May 2001
Location: USA
Posts: 30
Received 0 Votes on 0 Posts
Unhappy

I have a lennox heat pump that has a problem. It is a Lennox HP 22-311-3P. A couple of years back, I called my A/C company to come examine the very same problem. They found that the Cutler-Hammer single pole contactor was pitted and burned and needed to be replaced. They did so, charging me a whopping $75 for the part alone, then another $60 for the labor to change it out.

Yesterday, I noticed the unit was not cooling. The inside unit was running but the outside compressor unit was not. After taking the service cover off, I looked at the contactor and could see that it would not remain engaged. The pole contact at the top was pitted and scortched from many months of running. When I pushed the contactor's black button, the unit fired right up.

Today, I went to a supply house and purchased a new exact replacement for all of $12.76. However, after installing the new contactor and turning the unit on, it still would not start up unless I stood there and held the contactor's black button down.

Someone tell me what to troubleshoot next!?!

Thanks
 
Sponsored Links
  #2  
Old 05-04-01, 11:34 PM
Visiting Guest
Posts: n/a
Teddford,


Check control voltage. Smaller wire(s) going to contactor. Should be 24 volts ac.

 
  #3  
Old 05-05-01, 12:05 AM
Member
Join Date: Mar 2001
Location: Tennessee
Posts: 211
Received 0 Votes on 0 Posts
Contactor

Hi,

If you'll look at back of contactor,you'll see two small wires coming to it,one on each side.This is your coil which when energized with 24 volts from t-stat,magnitizes and pulls in the contacts to close circuit and start unit.You can turn off the 240 volt power at disconnect,set t-stat to cool and auto and temp lever to 60,then take a voltmeter set for highest setting above 24 volts AC and place one lead to each wire terminal.It should read 24 volts and contacts should be pulled in.Check where your t-stat wires enter unit for a reset button close by also and push it in once if one found.If you can't get 24 volts,you have a break in your 24 volt low voltage circuit.Make sure t-stat is set correctly cause that controls the contactor.Write back after you've checked these and we'll guide you from there if still not working.

Also, if any wires were burned/scorched,they'll have to be replaced.Check ALL connections thoroughly.

Take Care,

CoolBreeze
 
  #4  
Old 05-05-01, 03:31 AM
PDF
Visiting Guest
Posts: n/a
Make sure

They gave you a contactor with a 24volt coil.I know, on the outside of the box it said 24volts,but just check to make sure.Do as the others mentioned.Sounds like a loose terminal is causing that set of contacts to go bad.Your contactor should be rated for 30 amps.Is it?It will do no harm to install contactor with a 40 amp rating.PDF
 
  #5  
Old 05-05-01, 08:27 AM
Member
Thread Starter
Join Date: May 2001
Location: USA
Posts: 30
Received 0 Votes on 0 Posts
Talking It works!!!

Thank you so much guys! Rick, I tried the volt meter and it registered nothing.

Coolbreeze, I followed your directions to a tee! When I hit the reset button, it fired right up! I thank you so much...you saved me a very expensive service call!!!

(This sure does make me feel better about paying for internet access!)

If I can ever answer anything on concrete, you can bet that I will!
 
  #6  
Old 05-05-01, 11:20 AM
Member
Join Date: Mar 2001
Location: Tennessee
Posts: 211
Received 0 Votes on 0 Posts
Contactor

teddford,

You're very welcome.Glad we could help. I'd also like to commend you on a job well done.Now, kick back and enjoy the cool air!!! Take Care and Best Wishes.

CoolBreeze
 
  #7  
Old 05-18-01, 04:55 AM
Member
Thread Starter
Join Date: May 2001
Location: USA
Posts: 30
Received 0 Votes on 0 Posts
Re: Contactor

Well, I'm back again with a related problem. When I got home yesterday, the inside unit was running but the outside unit was not. I took the cover off of the outside unit and once I hit pushed the reset button, it started right up. That troubled me though since I shouldn't have to make that a routine.

I got up early this morning and noticed the outside unit once again was not running. Once again, I pushed the reset button and the unit acted as though it running but upon closer examination I noticed the fan was not running on the unit, but the unit sounded as though it was running. Not wanting to leave it in that condition, I pulled the breaker cutting off the power.

What do I look for now?

Originally posted by CoolBreeze
Hi,

If you'll look at back of contactor,you'll see two small wires coming to it,one on each side.This is your coil which when energized with 24 volts from t-stat,magnitizes and pulls in the contacts to close circuit and start unit.You can turn off the 240 volt power at disconnect,set t-stat to cool and auto and temp lever to 60,then take a voltmeter set for highest setting above 24 volts AC and place one lead to each wire terminal.It should read 24 volts and contacts should be pulled in.Check where your t-stat wires enter unit for a reset button close by also and push it in once if one found.If you can't get 24 volts,you have a break in your 24 volt low voltage circuit.Make sure t-stat is set correctly cause that controls the contactor.Write back after you've checked these and we'll guide you from there if still not working.

Also, if any wires were burned/scorched,they'll have to be replaced.Check ALL connections thoroughly.

Take Care,

CoolBreeze
 
  #8  
Old 05-18-01, 07:48 AM
Member
Join Date: Mar 2001
Location: Tennessee
Posts: 211
Received 0 Votes on 0 Posts
Continueing problem

Hi teddford,

I have not been on any of these websites/forums in the last 11 days due to a serious personal emergency situation in my immediate family, therefore this will have to be brief. However, there is a wealth of knowledge on here and I'm sure you will receive the help needed.

I will say that with your unit doing this a couple years back, then two weeks ago and again now,you have an ongoing problem that keeps getting a "Band-aid" instead of "Stitches".This will require volt,amp and ohm meters,refrigeration gauges,temperature probes,etc...,etc...
It will also require the knowledge/certifications if required in their use, to be able to use them systematically to trace your entire system electrically,pressures/temperatures wise to find not just the immediate problem, but the continueing cause behind it.

That should have been performed a couple years ago as part of the service fee.I understand your not wanting to pay an expensive service call and hopefully someone here can help you there,I can't at this time as this will be a back and forth process to guide you through it and I probably won't be on regular for some time. I will suggest you try to do what you can and look at everything carefully for a tale-tale sign, but if needed, a service call by a Qualified, Reputable Contractor may be best because if not corrected,it's going to eventually rear its ugly head and cost way more than the service fee to have found and corrected.

Hope this helps,I'm sorry I can't assist further. Take Care and Best Wishes.

CoolBreeze
 
  #9  
Old 05-18-01, 09:39 AM
Member
Thread Starter
Join Date: May 2001
Location: USA
Posts: 30
Received 0 Votes on 0 Posts
Unhappy Re: Continueing problem

Thanks for responding Coolbreeze. I'm so sorry to hear of your family emergency. I hope everything works out for you.

I was afraid that might be the case. If anyone on this board knows of a reputible A/C firm in Austin, Texas, Please let me know.

Thanks

Originally posted by CoolBreeze
Hi teddford,

I have not been on any of these websites/forums in the last 11 days due to a serious personal emergency situation in my immediate family, therefore this will have to be brief. However, there is a wealth of knowledge on here and I'm sure you will receive the help needed.

I will say that with your unit doing this a couple years back, then two weeks ago and again now,you have an ongoing problem that keeps getting a "Band-aid" instead of "Stitches".This will require volt,amp and ohm meters,refrigeration gauges,temperature probes,etc...,etc...
It will also require the knowledge/certifications if required in their use, to be able to use them systematically to trace your entire system electrically,pressures/temperatures wise to find not just the immediate problem, but the continueing cause behind it.

That should have been performed a couple years ago as part of the service fee.I understand your not wanting to pay an expensive service call and hopefully someone here can help you there,I can't at this time as this will be a back and forth process to guide you through it and I probably won't be on regular for some time. I will suggest you try to do what you can and look at everything carefully for a tale-tale sign, but if needed, a service call by a Qualified, Reputable Contractor may be best because if not corrected,it's going to eventually rear its ugly head and cost way more than the service fee to have found and corrected.

Hope this helps,I'm sorry I can't assist further. Take Care and Best Wishes.

CoolBreeze
 
  #10  
Old 05-18-01, 10:27 AM
Member
Join Date: Mar 2001
Location: Tennessee
Posts: 211
Received 0 Votes on 0 Posts
Thanks

Hi teddford,

Thanks for your concern.I have posted a request on another site that I'm a member of requesting the info for you and will post it as it arrives.Hang in there.Take Care.

CoolBreeze
 
  #11  
Old 05-18-01, 03:13 PM
PDF
Visiting Guest
Posts: n/a
Replace outside

fan motor.Your RESET you have been pushing is a high pressure cutout.The fan motor is crapping out and safety circuit is tripping.PDF
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
 
Ask a Question
Question Title:
Description:
Your question will be posted in: