AC compressor

Page 4 of 4  

As others have suggested. You can check to see if the outdoor unit has 220 VAC. You can also check to see if the contactor is getting the 24 VAC signal, and if the contactor is making connection.
The fan and compressor have different capacitors. Possible but not likely that they are both bad at the same time.
--
Christopher A. Young
Learn more about Jesus
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 8/23/2010 8:00 AM, Stormin Mormon wrote:

If it's a combo capacitor with 3 terminals, the top will pop up when it fails, killing both the fan and compressor.
TDD
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 22 Aug 2010 19:06:51 -0700 (PDT), ransley

My HVAC took a time-out a few weeks back. Nothing would work at all. The fan would not even run, like yours.
I presume the fan blower gets its 110V power from a light switch box in the attic. The switch had failed and no power was getting to the blower fan.
YMMV
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

If the inside unit is not working then it's likely that the 24 vac transformer is not getting power and that will explain why the outside unit doesn;t work. The op was not very clear about the inside half but I got the impression it was ok. I could easily be mistaken.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The air handler does work, and when I push in the relay on the outside compressor unit it runs, so I guess next I check for 24v to the compressor relay?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

On most of these the 24vac power comes out from the air handler to the outside unit. It's how the insde unit turns on the outside one. So yes, sounds like you should troubleshoot the 24vac. Start at the outside relay and work back to the air handler checking for 24vac when the inside unit is running in the cooling mode. The 24vac wire should be color coded so you can find it at the inside unit if you have to go back that far. Obviously if you have 24vac at the outside relay then you have a bad relay.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I forgot, to be safer you can usually turn off the outside unit while troubleshooting the 24vac. The inside unit supplies the 24vac.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

The air handler does work, and when I push in the relay on the outside compressor unit it runs, so I guess next I check for 24v to the compressor relay?
The only thing controlling the 24 volt system before it gets to the outside unit is thermostat. Are you sure it is good? Find the two wire cable and test for 24V there first.
Many of the 1995 and later models have a low pressure switch wired into the 24 volt system inside the condenser unit. This part might also be the problem. Just mentioning these two things BEFORE you run out and buy a non-returnable contactor.
Follow the 24V wires and test for current after each part. Entry point, low pressure switch and at the contactor. Actually working that in reverse is the smarter way to do it. I just wanted you to see the path.
--
Colbyt
Please come visit http://www.househomerepair.com
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 8/23/2010 2:18 PM, Colbyt wrote:

He did mention that it's a 13 SEER unit and it may very well have a low pressure cutout switch. The builder grade units, even the newest of them don't have a factory installed low or high pressure cutout.
TDD
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 8/23/2010 12:34 PM, ransley wrote:

Squirrels and other critters have been known to enjoy a meal of insulation.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 8/23/2010 1:34 PM, ransley wrote:

Did you happen to run a weed eater around the condensing unit? I see that activity cut the control wire to the condenser quite often.
TDD
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.