How to troubleshoot this ac?

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1) check for electric power. blown fuses.
2) check that t'sat is calling for cold.
3)check that fan can turn on both condenser and air unit. filters ect.
4) look for anything that is out of the ordinary.
5) hook up pressure gauges just to see if there is any refrigerate .
 
1) check for electric power. blown fuses.
2) check that t'sat is calling for cold.
3)check that fan can turn on both condenser and air unit. filters ect.
4) look for anything that is out of the ordinary.
5) hook up pressure gauges just to see if there is any refrigerate .

1. There are no electrical problems or tripped breakers that I can see.

2. The thermostat is calling for cold.

3. The fan turns on outside. I'm not sure what to be listening for on the inside unit. I can hear the furnace turn on when I set it to heat. But I never feel any air coming out of the registers.

I think I hear the inside fan trying to turn on when I set fan to "on" rather than "auto."

So should I open up the inside air handler? And look for what?
 
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I just changed the filter maybe 10 days ago. Could that be related to the problem? I changed it to the same size and brand that it previously had.

There's a brown stain on this new filter already and it's very wet. When I took it out, I thought the fan came on, but now it's not.

0224181737.jpg
 
Update: been doing some reading. I think the evaporator coils are iced. Maybe due to a blockage by the new filter?

But this is a new filter that was replacing a dirty one.

Should I go buy a new filter? How do I make sure this won't happen again?

0224181747.jpg
 
1thing that causes that is low Freon, also poor air flow from dirty coils. Fan not working.
 
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1thing that causes that is low Freon, also poor air flow from dirty coils.

Since the problem started around the same time I changed the filter, I think poor air flow is more likely. Especially since I think I heard the evaporator fan try to come on as soon as I took this filter out. All the registers in the house are open.

I just don't understand why putting a new filter in would cause this problem. And if I go get another, the problem may just happen again. Should the system work with NO filter in it? Should I try to get it working with no filter before I go out and get a new one?
 
the new filter doesn't have anything to do with your problem.
the problem was happening prior to the filter change cause the old filter was soaked by the melting evaporator coil ice.
shut the unit down until things thaw out, then try to run just the blower without heat or A/C. I suspect your blower system is bad or going bad. notice the speed of the blower in both heat and A/C mode as each setting will run at different speeds. could be your cooling winding is bad but heat windings are Ok.
let us know what you find.
 
the new filter doesn't have anything to do with your problem.
the problem was happening prior to the filter change cause the old filter was soaked by the melting evaporator coil ice.
shut the unit down until things thaw out, then try to run just the blower without heat or A/C. I suspect your blower system is bad or going bad. notice the speed of the blower in both heat and A/C mode as each setting will run at different speeds. could be your cooling winding is bad but heat windings are Ok.
let us know what you find.

How do you know the old filter was soaked? The filter in the picture is the new one from 10 days ago.

Should I take any of the panels off? Or just listen through the metal?
 
Because you said it was soaked.
Panels on or off as long as you can get an idea of the fan speed.
 
Because you said it was soaked.
Panels on or off as long as you can get an idea of the fan speed.

The new filter was soaked. I don't remember the old one being wet, just dirty.

So the problem might be the filter. Just wondering exactly why.
 
I still think the problem is with the blower motor. At least from what you have described. I can’t see hear or feel the unit so you’ll have to be my eyes and ears and I can only go based on what your saying.
Basically I think your not moving enough air across the colis to keep them from freezing and thawing and soaking the filter.
 
The machine worked fine before you changed the filter
The machine stopped working when you replaced the filter

Maybe you didn't put the filter in right or you didn't close the unit up correctly.
 
I left it running for 8 days, set on 72 degree "Cool" and the fan set on "Auto" with no filter in.

When I got here, the house was 72 degrees, but not sure it was running because that's about the same temperature it is outside.

The ice seems to have melted from the evaporator coils, however.

I turned the fan to "On" and I think it hums, but doesn't turn on. This is what it sounds like.

https://www.dropbox.com/s/940rwxvzt65zqqu/0304181820.mp4?dl=0
 
I left it running for 8 days, set on 72 degree "Cool" and the fan set on "Auto" with no filter in.

When I got here, the house was 72 degrees, but not sure it was running because that's about the same temperature it is outside.

The ice seems to have melted from the evaporator coils, however.

I turned the fan to "On" and I think it hums, but doesn't turn on. This is what it sounds like.

https://www.dropbox.com/s/940rwxvzt65zqqu/0304181820.mp4?dl=0

Bingo!! That's what I was referring to. Either the motor or capacitor or both are bad as long as your getting proper voltage to the windings. Do you have any meters to test these components?
 
Bingo!! That's what I was referring to. Either the motor or capacitor or both are bad as long as your getting proper voltage to the windings. Do you have any meters to test these components?

No. What should I buy?

And I still find it interesting that this problem started the same time I changed the filter. Guess it's just a coincidence.
 
well, it hums because something is wrong.
could be not getting enough voltage.
that is why i asked about a meter.
you have a couple of choices here.
buy a meter and find the faulty component(s) or just by new until the problem goes away.
your first and cheapest option is to replace the capacitor. if you don't have a meter to read it then maybe the supply house can test it for you.
otherwise, gamble $20, replace it and see what happens.
if capacitor is good and voltage is good then it will be the blower motor itself that is bad.
 
well, it hums because something is wrong.
could be not getting enough voltage.
that is why i asked about a meter.
you have a couple of choices here.
buy a meter and find the faulty component(s) or just by new until the problem goes away.
your first and cheapest option is to replace the capacitor. if you don't have a meter to read it then maybe the supply house can test it for you.
otherwise, gamble $20, replace it and see what happens.
if capacitor is good and voltage is good then it will be the blower motor itself that is bad.

Where do I buy a capacitor from?

I've been reading that a capacitor problem can originally trace back to a blocked filter. All these problems started when I changed the filter. I don't get why a brand new filter of the same size and brand as the old one would cause an issue.
 
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