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York AC unit running slow...Please help :^(

19K views 52 replies 8 participants last post by  beenthere 
#1 ·
I had to turn on the AC for the first time this season today and the vents were blowing out worm air.
I went out to check if the outside unit was on and it was.
The strange thing is that both the fan and pump are on but seem to be running much slower than normal.
The high line is not getting hot and the low line is not getting cold.

I believe that the fan and pump are single stage and the capacitor is a "dual run capacitor" not a "start capacitor"

Question is..
Can the dual run capacitor be bad but still be able to run the unit at a slower speed?
If the freon was low, wouldn't the low pressure switch not allow the unit to come on at all?
Is there anything else that can cause this?
Please help...Due to the economy I am unemployed and cannot pay to have a tech come out :^(
 
#4 ·
Guess I will try a new run capacitor.

In the event that doesn't work....what else can the problem be?

Might I add that I do NOT have to start anything by hand......Just seems like the pump and fan speed is at about 60%

Would it cut down the speed on the two if it were low on freon?

This unit is only about 6-7 years old.

I have read about a 24 Volts at a certain location on the unit.....can anyone tell me exactly where so I can check it?

At the contactor I seem to have 238 Volts
 
#5 · (Edited)
A weak capacitor can cause the fan to run slower.

The 24 volts is the control voltage. Which has no bearing on compressor or fan speed. But would be checked across the contactors 24 volt coil.

Low of refrigerant wouldn't cause the fan to spin slower.
 
#6 ·
A weak capacitor can cause the fan to run slower.

The 24 volts is the control voltage. Which has no bearing on compressor or fan speed. But would be checked across the contactors 24 volt coil.

Low of refrigerant would cause the fan to spin slower.
I just installed a new dual run capacitor and it made no difference.

You say that being low on refrigerant will tell the unit to cut down the fan/pump speed to keep from freezing up?
 
#9 ·
Is it really slowed down. or does it just look that way to you, now that its not cooling right. Lots of people don't take notice tot he fan speed when their A/C is working.

You may have had 238 volts at the contactor when the A/C wasn't running. But what is the voltage when it is running.
 
#10 ·
I take notice to the fan speed all the time.....now that its slower.....I can hear the pump, has a slight gargling buzzing noise, but I do believe its running. Figured it always sounded like that....just more noticeable with out the fan at full blast. Pretty much sound like a normal compressor to me.

I checked the Volts and it is 238 to 239 on the feed side when off.......and 238 to 239 on both sides when on.

In addition.....last year it was not working so well and the High line WAS getting hot, but the Low line was NOT getting cold.

Now it wont even do that.
 
#11 ·
A slow running fan could cause the small line to get very hot.

So if its running slow, and the small line isn't getting hot. You have more trouble then just a slow running fan.

Might be time to bite the bullet, and call a tech to diagnose it. Might be a dirty condenser coil, and a low charge caused by a leak.

Have you checked the amp draw when the unit is running.
 
#17 ·
Doubt its rated to run a high load through it. Generally need a clamp on attachment. To clamp around the wire.

What amp listing is at the ACA setting.
 
#29 ·
+1.... I'm not HVAC but after replacing my Dual -Run Capacitor I could not get my compressor to start until I replaced the contactor which was not expensive to replace. My condensor fan was rotating slowly and the compressor was not running when I found the DRC rusty and bulging.

Not to change the subject....but still somewhat relevant ...what type of meter should I purchase to measure a capacitor's capacitance for yearly HVAC maintenance?
 
#24 · (Edited)
I really do not think it is a two speed.....I have never seen it run slower until now......It is 90 degrees in TX today

I hear the pump doing something but I'm not sure if its not doing anything or if the freon is bone dry.

The contact points have been cleaned....no change

Here is what the gauges read when its running with the red on the high, and the blue on the low.

 
#25 ·
If the compressor is running. Your just about out of refrigerant. Even if its not running, your just about out of gas. Looks like it has a few ounces in it.

Needs to be leaked checked. And the leak repaired. And then it can be recharged.
 
#26 ·
Shut it off ASAP. Looks like it has no freon and the compressor will now overheat and get damaged! Even a 1/2 lb sitting idle should get you a higher reading. Looks like you just have air in there now.
 
#27 ·
Its off.....

I only had it running for 5-10 min max

The outside unit is under warranty so if the leak is in the unit they will have to fix it free of charge.
If the leak is between the unit and the attic.........Well I guess I get to spent $400 plus to have the leak found and fixed, and about 8 pounds of r22 :furious:

And I still dunno why the fan is running slow. :censored:
 
#28 · (Edited)
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