Condenser Not Kicking On


  #1  
Old 04-28-09, 04:49 PM
A
Member
Thread Starter
Join Date: Apr 2009
Location: Midwest
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Condenser Not Kicking On

A couple of days ago, my A/C condenser stopped kicking on. The fan ran fine, but contactor was clicking. The condenser worked when I manually engaged the contactor. Replaced the contactor and everything worked fine.

Ran the A/C for a day and half, and now I am getting the same thing. I checked continuity and voltage on contactor and relay - everything looks good. I checked circuit board and fuse on air handler - good. No obvious damage (bulge, collapse) of capacitor -- I replaced that a couple of years ago, but I do not have a capacitor tester.

Any ideas?
 
  #2  
Old 04-29-09, 04:15 AM
dun11's Avatar
Member
Join Date: Feb 2009
Location: Local
Posts: 753
Upvotes: 0
Received 1 Upvote on 1 Post
Does the cond fan still run fine ?
 
  #3  
Old 04-29-09, 04:25 AM
A
Member
Thread Starter
Join Date: Apr 2009
Location: Midwest
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Condenser fan kicks on fine if contactor is manually pushed in.
 
  #4  
Old 04-29-09, 04:37 AM
dun11's Avatar
Member
Join Date: Feb 2009
Location: Local
Posts: 753
Upvotes: 0
Received 1 Upvote on 1 Post
Does the comp try to start ?

Is it hot ?
 
  #5  
Old 04-29-09, 05:53 AM
A
Member
Thread Starter
Join Date: Apr 2009
Location: Midwest
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Condenser does not try to start unless contactor is manually engaged -- manually push contactor in, it starts right up. Release the contactor and it stops immediately. It is getting 24v from thermostat, but it just clicks and does not engage.

Checked continuity and voltages on contactor and time delay relay, and everything looks good. Checked for blown fuse at circuit board on furnace/air handler - good.
 
  #6  
Old 04-29-09, 06:23 AM
dun11's Avatar
Member
Join Date: Feb 2009
Location: Local
Posts: 753
Upvotes: 0
Received 1 Upvote on 1 Post
OK to clarify, you get a good 24v from transformer to coil of contactor when there is a call for cooling, all elec connections on contactor are clean and tight but contactor does not pull in ?
 
  #7  
Old 04-29-09, 06:43 AM
A
Member
Thread Starter
Join Date: Apr 2009
Location: Midwest
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
"OK to clarify, you get a good 24v from transformer to coil of contactor when there is a call for cooling, all elec connections on contactor are clean and tight but contactor does not pull in"

Exactly.
 
  #8  
Old 04-29-09, 06:55 AM
dun11's Avatar
Member
Join Date: Feb 2009
Location: Local
Posts: 753
Upvotes: 0
Received 1 Upvote on 1 Post
replace contactor, make sure you get one that has the correct FLA rating
 
  #9  
Old 04-29-09, 07:25 AM
A
Member
Thread Starter
Join Date: Apr 2009
Location: Midwest
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Since I did that originally, and it only solved the problem for a day and a half, I want to make sure there is not something else that could be causing the contactor to fail. I suppose it is possible I just got a bad contactor, but is there anything else I could/should look at?
 
  #10  
Old 04-29-09, 07:30 AM
dun11's Avatar
Member
Join Date: Feb 2009
Location: Local
Posts: 753
Upvotes: 0
Received 1 Upvote on 1 Post
You can chk incoming line voltage, also look to see if something is shorting out the coil on contactor.

Does the coil have continuity now ?
 
  #11  
Old 04-29-09, 08:24 AM
A
Member
Thread Starter
Join Date: Apr 2009
Location: Midwest
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
At work right now, so I can't recheck. But last night I was getting 240v on incoming line. After work I will recheck continuity and voltages.
 
 

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