A/c Humming - Electrical - DIY Chatroom Home Improvement Forum

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical


Thread Tools Display Modes
Old 01-07-2013, 08:08 AM   #1
Join Date: Jan 2013
Posts: 1
Rewards Points: 10

a/c humming

my a/c outside is making a humming noise and I do not have it turned on in my house?


avabean is offline   Reply With Quote
Old 01-07-2013, 08:36 AM   #2
Electrical Contractor
rrolleston's Avatar
Join Date: Oct 2011
Location: Granville, NY
Posts: 1,988
Rewards Points: 1,012
Send a message via AIM to rrolleston Send a message via Yahoo to rrolleston

Did you also try turning off your ac disconnect outside?


With Electricity there is the right way to do it and the dead way. Just because it works does not make it safe.
rrolleston is offline   Reply With Quote
Old 01-07-2013, 08:38 AM   #3
Join Date: Nov 2011
Location: Hartfield VA
Posts: 34,581
Rewards Points: 14,294

Can be a bad contactor.
joecaption is online now   Reply With Quote
Old 01-07-2013, 08:42 AM   #4
I'm Your Huckleberry
Join Date: Mar 2011
Posts: 5,884
Rewards Points: 2,270

If you mean the outside condenser is humming although you don't have the thermostat set on call for cool (when was the last time you did have it on cool?) than it could be a combination stuck contactor (allowing power to get to the capacitor) and/or (if a single leg contactor and one leg of 120 volts is constant) simply a bad capacitor.

What kind of condenser is it? Is it a heat pump? Does it work when you turn it on?
Doc Holliday is offline   Reply With Quote
Old 01-07-2013, 09:06 AM   #5
Join Date: Sep 2008
Location: Oregon
Posts: 1,497
Rewards Points: 500

"Heat pumps" use the outside unit for heating. Is it a heat pump?

And they are making these very efficient lately. If it is just humming but the fan is not going, that could be a normal "minimal heat needed" operating mode. Write down the model numbers and call the manufacturer or look at their web site for an owner's manual - which should explain various modes of operation.
Billy_Bob is offline   Reply With Quote
Old 01-07-2013, 05:01 PM   #6
dmxtothemax's Avatar
Join Date: Oct 2010
Location: Brisbane, Australia.
Posts: 4,321
Rewards Points: 5,600

Could be a noisy power transformer used for control circuits !
dmxtothemax is offline   Reply With Quote
Old 01-07-2013, 08:14 PM   #7
Join Date: Dec 2011
Location: Huntsville, AL USA
Posts: 276
Rewards Points: 240

If it's a heat pump, and it has one of the old mechanical thermostats, it's normal that sometimes these thermostats apply power to the reversing valve even though no heat or cooling is being called for.


fa_f3_20 is offline   Reply With Quote

Thread Tools
Display Modes

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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Water Pipes Humming Smoke Plumbing 18 02-26-2013 06:24 PM
jet spa tub power is off but still humming sound Ruben Lewis Plumbing 0 01-18-2012 07:48 PM
humming water pipes noelcon Plumbing 0 09-04-2010 11:43 AM
Terrible humming in pipes purplepirate Plumbing 17 07-15-2010 11:09 AM
Trane 1100 XE- Outside unit making humming noise Momof2 HVAC 0 09-03-2009 11:25 AM

Top of Page | View New Posts


Search Engine Friendly URLs by vBSEO 3.6.1