Fan only staying on for a few seconds and then shutting off- AC not cooling

[Ron Van]

Believe it or not, horizontal flow outdoor combination units are not unseen way up here in Michigan. Not common, but not unseen. They're most often found at houses with crawl spaces instead of basements.

Reading your post sparked a lot of memories! Our house has a crawlspace and the horizontal HVAC was added sometime after the house was built. The duct runs into the crawlspace and is so big that it effectively cuts the crawlspace in half.

I did a lot of projects on the house that required me to crawl, on my hands and knees, from the access hole, the length of the house, to go around the big duct and then crawl back the length of the house to get to what I wanted to work on.

I finally decided to cut an access hole in our closet to shorten the crawl time. First, I had to build the closet…



And then the access hole.

 

[PJB12]

Oh I Feel Your Pain! (Your project looks great, by the way!)

My friend's house that I mentioned in #20 also has the duct where I'd have to crawl to the end and go around it (then remember that I forgot a tool or part). Re-wiring that house took about 10 times as long as if it had a basement or attic.

My wife's parents' home in northern Michigan had such a short crawl that I'd have to take a little, folding shovel to dig a trench so that I could roll over. From about September through May the ground was frozen, preventing the digging.

Guess I'm spoiled with basements!

Paul

 

[havasu]

The problem you may be facing is that this little noise you hear today, may end up being a huge noise tomorrow, if in fact those bearings are toast.

 

[zannej]

I hope that isn't the case, Havasu. I'll have to see if my phone can record the sound later on. It is actually less noisy now than it was the day it was put in. It's still noisy, but not as noisy.

 

[havasu]

I read your A/C quit again? Do you think it was due to that noisy bearing?

 

[zannej]

I don't think so. I think there is a loose wire. Usually when I put in the thermostat to turn AC OFF, the whole thing shuts off, even the fan. But its not shutting off. The fan keeps running. The outside unit will turn on and off though. Twice now I've had to turn the power off and then back on and wait several minutes before turning it back to automatic or cool for it to start cooling again. I also discovered that the flap in my bedroom ceiling vent isn't open very far, but since the chain is missing and the vent cover is hanging down, I don't have a way to fix it and am not sure now. I pushed it with a back scratcher but it went back in place. I need to get a new chain on it, get the vent back in place, and get the vent flap to open. I also need to vacuum it out before I do anything because it looks filthy up there.

 

[PJB12]

That machine is giving you so much trouble, Zannej, I wonder if it's wise to bring in a different repair contractor to check the system out completely & get rid of all the problems.
Paul

 

[zannej]

Finding reliable people in this area isn't easy. But if it gives me more trouble I'll look into it. The outside unit now seems to be working fine. The inside unit might need some work at some point. It's 70°F in the hallway but hot and humid in my room- and I have my door open to let cooler air come in from the hallway. I need to fix the vent thingy on my ceiling.

I don't think the thunderstorms and power outages did any favors to the system. Last 2 days the power has been blinking on and off and it was out for a few hours this morning and afternoon. Wind and rain tend to affect the power because my power company sucks. They just raised the rates for all of the customers but all of it is going to the new CEO of the company who immediately doubled his pay when he took the job.

 

[zannej]

Fan seems to be on permanently. But right now the AC isn't cooling.

Compressor outside is running. I poured bleach down condensate line and put the cap back on. I just changed the filter.

Might have to try turning off the breaker again. I tried turning the AC off for about 10min from the wifi controls but I think the breaker has to be turned off and on. Just not feeling up to that with the heat and being sick.

 

[havasu]

Fan should be on auto, not "on".

 

[zannej]

Fan should be on auto, not "on".

It's on Auto but it NEVER shuts off. There is no OFF for it for some reason. Ever since they changed out the fan on the inside unit it runs constantly.

I wonder if the internet cable falling into the unit and getting cut in half interfered with the AC's functions. At least, that's what I think happened. Looks like some sort of blade cut it and I don't think anyone came in the yard to cut it. If its not one thing its another.

 

[havasu]

I saw a pic and it looks like it was eaten by an animal?

 

[PJB12]

Hi Zannej,
I saw in the photo the the unit System control is on Auto. Perhaps try moving it to Cool, even though the thermostat says it's cooling. We had a thermostat the would lose its mind when on Auto. The thermostat would say "Cooling", but the outdoor (condensing) unit would not function. I'd have to turn the breaker to the outdoor and indoor units to "jump start" it. I ditched the thermostat and put in an ecobee3 Lite & haven't had troubles since. (Power company web site had it really cheap.)

When the outdoor unit is running, is the Suction Line (the larger of the two) cool and sweating? Is the liquid line warm?
These are clues that will tell you that the outdoor unit is functioning. Then, you'll turn your attention to the indoor unit. Clogged filter and indoor fan not running at cooling speed are common.
Is there ice or frost on the suction line? This will tell you that most likely insufficient air is moving past the evaporator. There are other causes, such as low charge, but lack of air flow is common.

On many units, if a safety tells the outdoor unit to shut off, there is either a time delay, a wait for equalization or it stays off until the breaker is reset. If the indoor air is not moving properly the unit may shut off on low pressure (assuming the unit has a low pressure safety). Some units will restart after a time period and some need the breaker flipping.

I hope one of these ideas saves you from a service call!
Paul

 

[zannej]

Havasu, it had slice marks on it rather than tooth marks. It looks like it was cut-- consistent with the fan blade of the AC unit-- and the location was near the AC unit.

PJB12, I'll have to check and see. The lines going into the inside unit are wrapped in some kind of insulation.

 

[PJB12]

Havasu, it had slice marks on it rather than tooth marks. It looks like it was cut-- consistent with the fan blade of the AC unit-- and the location was near the AC unit.

PJB12, I'll have to check and see. The lines going into the inside unit are wrapped in some kind of insulation.

You should feel the lines for temperature and condensation where they exit the outdoor unit's cabinet instead of indoors.

Right at the cabinet you may see the service valves. They are where the pipes from the house end. The insulation will end there. You should be able to push it back enough to feel the pipe.

Paul

 

[zannej]

You should feel the lines for temperature and condensation where they exit the outdoor unit's cabinet instead of indoors.

Right at the cabinet you may see the service valves. They are where the pipes from the house end. The insulation will end there. You should be able to push it back enough to feel the pipe.

Paul

Ah, I'll have to do some weedeating before I can get over to check that. Blackberry bushes are in the way. And there's a pit directly next to the air conditioner. I'm going to have to put up something to stop the ground erosion there.

Thanks for the info!

 

[zannej]

We had a massive power surge where the power blinked on and off rapidly more than 10x. It had a few times where it was off for about 20 seconds and then back on for about 10 seconds then off. Then it was off for a few minutes and came back on for a few minutes and then went back out for 6+ hours. Ever since then the AC hasn't been cooling to 70. The outside unit has been shutting off entirely. It didn't come back on after the power outage and I had to turn it to off at the thermostat and then flip the breakers (There are two marked AC). I did that, waited a few minutes, flipped them back on, waited several minutes and then turned it to Cool. 1st time compressor kicked on right away. 2nd time it took about 10min before it kicked on. Last time it seems to have kicked on right away. But it turns off after awhile and starts getting hot again. Not sure what the deal is. Guessing something got loose or fried a bit.

 

[PJB12]

We had a massive power surge where the power blinked on and off rapidly more than 10x. It had a few times where it was off for about 20 seconds and then back on for about 10 seconds then off. Then it was off for a few minutes and came back on for a few minutes and then went back out for 6+ hours. Ever since then the AC hasn't been cooling to 70. The outside unit has been shutting off entirely. It didn't come back on after the power outage and I had to turn it to off at the thermostat and then flip the breakers (There are two marked AC). I did that, waited a few minutes, flipped them back on, waited several minutes and then turned it to Cool. 1st time compressor kicked on right away. 2nd time it took about 10min before it kicked on. Last time it seems to have kicked on right away. But it turns off after awhile and starts getting hot again. Not sure what the deal is. Guessing something got loose or fried a bit.

Sometimes when a unti won't turn back on right away it's because either the outdoor unit or the thermostat has a purposeful delay-on-make timer. This is to prevent damage to the compressor by trying to start against high pressure in the discharge line. More on that is below.

Other times, delay in starting is due to high head pressure still in the compressor discharge line. The compressor has a hard time overcoming that pressure. It takes a few minutes for the suction and discharge pressures to equalize. (The reason some units and thermostats have the delay mentioned above)

And, you could have a weak starting capacitor for the compressor. If you don't have a capacitance meter, a local motor repair shop will test it for you if you bring it to them. If you have two, it will be the round one.

CAPACITOR CAUTION!!! After you lock off power to the unit, wait a very long time (many hours) before disconnecting the capacitor. They store electrical energy for a living. Lots of energy!

The stored energy takes time to discharge. Some capacitors have bleed resistors across the terminals that will speed the discharge- IF THE RESISTOR STILL WORKS.

Or, some people short across the terminals with a screwdriver. If you're inclined to try this, wear full goggle protective eye wear, Sometimes capacitors explode, throwing shrapnel. I never do this and don't recommend it. I have a bleed resistor with clips in the tool kit instead- along with properly insulated tools and insulated gloves.

Power Failures-
On-Off power is not good for the unit. Perhaps look into a whole home surge protector.
It won't help with dips in voltage, but will help catch the surge voltage when power recovers.

Paul

 

[zannej]

I wanted to get an easy start thing for the system so it wouldn't jolt too much when starting and I have a whole house surge protector somewhere...

What I've found is that if I turn the condenser OFF with the thermostat and then flip the breaker off and on (waiting at least 10 seconds in between) and then wait like 10min before turning the condenser back to "cool" it will start to cool, but over time it stops cooling. The entire condenser has shut off several times and I had to do this to restart it.

It was still on but not cooling so I did the off and breaker thing and just turned it back on again. It came down 1 degree thus far. But it doesn't get below 79.

Meanwhile, the blower motor fan never stops running. It's the "new" used one they put in and I don't know if it is wired properly or what the deal is.

Just called them again but still getting answering machine and no callback. They are open on weekends.

 

[zannej]

Turns out the coolant was low. They refilled it and let it defrost a bit, water came pouring out the condensate line. It's now nice and cool inside.
Cost $400 for the trip and the coolant, but its worth it to have it be so much cooler inside.