Curious and unwelcome AC problem, never happened before


  #1  
Old 06-02-16, 02:11 PM
J
Member
Thread Starter
Join Date: Jul 2015
Location: USA
Posts: 39
Upvotes: 0
Received 0 Upvotes on 0 Posts
Curious and unwelcome AC problem, never happened before

Have had other problems over the years but this is a first. And it being June, temperatures expected to be humid and miserable soon so perfect timing.

The AC outside unit runs perfectly fine, when AC is turned on at the switch. However, the inside central fan will not. So, running box in yard, dead vents. This is bad news because if left unattended, outside box will run 24/7 and electric bill skyrockets..... not to mention any other problems it could cause.

For awhile if I clicked on the FAN ONLY, the central fan would start, and I could even flip it over to AC and get some cool air. And, if I left the AC off say all day, for a few days if I turned the AC on around say 9pm when it was cooler outside it would start the central fan and run properly all night. But back to box outside running dead central fan come around 9am.

Now, AC will not start the central fan ever, and half the time when I turn the FAN ONLY on, it won't come on either. So things have been gradually "dying".
It appears to be some kind of switch, sensor or part that is going out although someone has mentioned possibly the A-coil icing... which I cannot find or get to, or have ever heard of.

Its a not-so- Dependable Ninety-Two. by Janitrol. New batteries in thermostat, all working fine on that end.
Has anyone ever seen this happen before?
 
  #2  
Old 06-02-16, 03:07 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,996
Received 4,155 Upvotes on 3,731 Posts
We have seen many things happen. We also service by what we can see. Your descriptions are what we "see".

You need to narrow down exactly what's happening. Your A/C is made up of two distinct units.... an outside part called a condensor and an inside part called an air handler...... or furnace if you have gas heat..... that contains the blower.

When you put the stat into FAN ON mode.... does the blower always come on ?
If not you have a blower problem. If the blower doesn't run.... the A-coil will ice over.
Your blower motor could require a new capacitor or the motor itself needs to be replaced.

When you put that stat in A/C mode and set stat to call for cool..... the blower should start immediately. There may be a 3-5 minute delay before the outside condensor starts up.
 
  #3  
Old 06-02-16, 08:43 PM
J
Member
Thread Starter
Join Date: Jul 2015
Location: USA
Posts: 39
Upvotes: 0
Received 0 Upvotes on 0 Posts
Up until today, when I put the stat into FAN ON mode, the fan would start.
Now it does not.
The condenser is working, the air handler is not.
Now when you say the blower motor needs a new capacitor, you mean the start capacitor? And would it be this part here?


And as I've already recently hired a plumber and an electrician and paid them hundreds of dollars, is this at least something I can swap the part out to try?
Perhaps the entire motor is not burned out. Unlikely with my luck, but not impossible....
 
Attached Images  
  #4  
Old 06-02-16, 09:00 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,996
Received 4,155 Upvotes on 3,731 Posts
Yes... that is the capacitor. Looks like 10uf at 370vac.

You may find a round replacement.... if not oval is also ok.


CAPACITOR-METALLIZED-370VAC-CONNECT-TERMINALS


While you're poking around down there.... make sure the blower spins freely. If it does.... put the access cover back on and turn the blower on for a few minutes. Turn the power back off, open the cover and see if the motor is warm. If yes... good indication it's the cap.
 
 

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