Calling HVAC experts...

[Jeff7181]

The air conditioning went out in my condo... again. I had it serviced almost exactly a year ago by a well known local heating and cooling company. I've been trying to dig up the invoice to remind myself of exactly what they did, but I can't find it. I believe the compressor was locked up so they rebuilt the compressor, replaced the compressor motor and flushed the system of debris. The bill came to $1074.95 (they have a lifetime warranty on repairs, so I'm expecting them to fix it for free this time - have an appointment scheduled for Friday).

Now it's not working again. I hear it turn on and it's not making any unusual noise like it was last time, it's just not cooling. I've cleaned off the condenser so air flow through it should be good - I even checked the "hot" side and it's no warmer than the outside air. I don't think it's a problem with a fuse or circuit breaker since I can hear the compressor turn on.

The unit that I have is made by Armstrong and it says "direct vent forced air furnace with cooling unit" model number 51hwc182-2. It's probably 20 years old, but having a freshly rebuilt compressor and new motor makes me think it should be like new save for the plumbing for the refrigerant, electronics and the condenser fan.

Any suggestions on anything I can try myself? I've shut it off and turned it back on a couple different times in the last couple hours in case there was some debris in the system blocking whatever type of orifice this system uses. No luck.

 

[mshan]

If your condo air handler is in attic like mine, go up there and see if the tubing for the return of air has collapsed and air handller isn't getting enough air. You can also just turn on ac and feel at air vent if flow of air is drastically reduced from what it used to be.

HVAC tech measured diameter of the round flexible tubing and then brought replacment tubing in. Just took the aluminum tape off, replaced it, then resealed it with tape or screws.

He charged a lot for what appears to be easy fix if you can get appropriate diameter length of correct tubing from hvac wholesale warehouse.

If you have leak in refrigerant line, refilling with presumably now outlawed refrigerant will be more expensive, but someone in another thread said there is some sort of sealant you can put into system to plug hole temporarily for a year or so.

Other issue lots of people have had is failed start-up capacitor or having system that never had one and now compressor is having a hard time getting kick started to cycle one.

 

[Jeff7181]

Thanks for the suggestions... mine is a closet furnace/AC unit. Could be a refrigerant leak, but given that they said there was debris in there the last time they worked on it, I suppose it could be debris again. They had it at their shop for 3 days fixing/cleaning it.

Makes me wish I bought the appliance insurance from the local energy company. I think I'm going to now... I think it's $10/mo or something like that.

 

[LurkerPrime]

Could be alot of things from the information you provided. Answering some simple questions could help us locate your issue.

Is air flowing through the vents in your condo? Is the amount of airflow normal, or barely noticeable? Is the air cold, slighly cooler, or same temp as rest of the condo?

Have you actually checked all your breakers? There is usually a set outside for your compressor/ condensor cooling fan and one for your normal inside breaker box for the blower fan in the evaporator/air handler (usually in the attic).

Have you checked the drip pan for the part in the attic for lots of water? Some A/C units have water sensors that automatically shut your compressor or whole system down if the drip pan starts to fill.

All those things are relatively easy things to check yourself and can help you diagnose the problem. Failed start-up capacitors seem to be the largest point of failure, and are a pretty cheap repair.

 

[lokiju]

Sounds like the capacitor on the Compressor/outside unit.

Part cost $10 to $20 but typically it's hard to find locally if you're not a HVAC person.

Had mine die (again) after 1 year of having it die before.

From what I've read, ever since GE sold off the manufacturing of the capacitors that everyone used to use, the void has been filled by companies that make really crappy ones that tend to die every year now.

If it does end up being the capacitor, you can find out the specs/model and then just order one from an online seller to keep on hand should you encounter this again.

 

[Jeff7181]

Could be alot of things from the information you provided. Answering some simple questions could help us locate your issue.

Is air flowing through the vents in your condo? Is the amount of airflow normal, or barely noticeable? Is the air cold, slighly cooler, or same temp as rest of the condo?

Air is flowing normally, it's just not cool, it's room temp.

Have you actually checked all your breakers? There is usually a set outside for your compressor/ condensor cooling fan and one for your normal inside breaker box for the blower fan in the evaporator/air handler (usually in the attic).

Yes, unless there's an internal breaker that's not visible just by taking off the panel that exposes the air filter.

Have you checked the drip pan for the part in the attic for lots of water? Some A/C units have water sensors that automatically shut your compressor or whole system down if the drip pan starts to fill.

No, it drains outside the condo as has been flowing fine all season so I have no reason to believe it's clogged.

All those things are relatively easy things to check yourself and can help you diagnose the problem. Failed start-up capacitors seem to be the largest point of failure, and are a pretty cheap repair.

As far as I can tell, the compressor and condenser fan are turning on normally.

I have someone coming out in the next couple hours to look at it. If they can tell me what's wrong, I'll go back to the place that fixed it last summer and see if they'll do it for free under warranty.

 

[Jeff7181]

Well... the compressor actually isn't coming on. Appears to be seized. It's still under warranty so I should be able to get it fixed for free... the bad news is they can't start on it until Friday, which means it'll be next week before they have a new compressor installed and bring it back here.

 

[LurkerPrime]

Well... the compressor actually isn't coming on. Appears to be seized. It's still under warranty so I should be able to get it fixed for free... the bad news is they can't start on it until Friday, which means it'll be next week before they have a new compressor installed and bring it back here.

Well at least its under warranty. Not having A/C till next week is going to suck big time though. You can pick up a decent sized window unit for around 100-150 bucks and that should at least keep one room in your house at a liveable temp.

 

[Jeff7181]

We have windows that crank out, so a window unit won't work unfortunately.

 

[Codewiz]

Well... the compressor actually isn't coming on. Appears to be seized. It's still under warranty so I should be able to get it fixed for free... the bad news is they can't start on it until Friday, which means it'll be next week before they have a new compressor installed and bring it back here.

Why do you say it is seized? Just because it doesn't turn on?

The post above about the capacitor could be the cause. Without the startup capacitor the fan will not turn without help.

The capacitor is a $10 part. Just had mine replaced for a huge fee.

 

[LurkerPrime]

Why do you say it is seized? Just because it doesn't turn on?

The post above about the capacitor could be the cause. Without the startup capacitor the fan will not turn without help.

The capacitor is a $10 part. Just had mine replaced for a huge fee.

He had a repair man out to the house. I sure as hell hope they know the difference between a bad cap and a siezed compressor. Although if A/C repair guys are anything like mechanics, then well they could have lied to him.

As for window units not fitting, that sucks. They do make other semi-portable indoor units, but they aren't nearly as cheap as the standard window unit.

 

[skull]

Well... the compressor actually isn't coming on. Appears to be seized. It's still under warranty so I should be able to get it fixed for free... the bad news is they can't start on it until Friday, which means it'll be next week before they have a new compressor installed and bring it back here.

Once a compressor burns out you should just replace the whole system. The debris they tried cleaning out is the acid created from the old compressors windings breaking down. Needless to say the acid is hard to clean out and there is a chance this will keep happening. I would never replace a compressor on a 20 year old unit. I would be reluctant doing it on a 6 year old system even after explaining everything to the customer.

 

[squirrel dog]

Skull is spot on,Jeff.I have a Rudd 5ton central a/c with an Attic air handler.It was 18 yrears old.The compressor began making knocking noises.I called out a trusted hvac company.I was told that they could rebuild the compressor for $1000,with a one year warranty on parts only,not labor,or I could get a sear16 rudd with a 10 year warranty for 5700.I went with new.20 yrs is quite a run for an ac of any type.

 

[Jeff7181]

At work we have a spare 5 ton Liebert sitting in storage... hmmmmmm... haha, that would be nice.

I didn't even consider replacing the entire AC unit last year when I had it serviced because I don't plan to stay in this condo very long. I just thought I'd get more than a year out of it.

The way things are looking, my girlfriend and I might be in this place for a while longer so maybe it would be smart to get a whole new unit. Then again... I've also thought about getting some "appliance insurance" from the local electric company. For $26 per month I can get the refrigerator, furnace and AC, washer, dryer, oven/stove and water heater covered. For another $10 per month I can get the microwave and dish washer covered too. I'm thinking of trying to get it all covered because the refrigerator, washer and dryer are the only appliances I bought new when I moved in. As far as I know, the rest is all 20 years old. So if they'll fix the AC for free, I buy this insurance, and it breaks next year... maybe then I get a brand new one at no cost to me?