A/C Compressor Failure, Domino Effect?

[Designer]

Hello everyone,
Yesterday I found out that I am fairly ignorant with respect to component interaction knowledge of the standard home a/c system. I have the standard system with the outdoor unit and the indoor furnace/blower. Long story short, the air coming out of the vents is not cold but the system still runs. The repairman yesterday said he thinks the compressor has gone out because the A coil is not cold at all, and the line pressures are off. He does not think the system is low on refrigerant. He had also mentioned that the TCV could be malfunctioning. So my question is: If the compressor has failed, would this have any downstream effects on the rest of the system (i.e. TCV), or would a replacement compressor (or whole outdoor unit) just make the whole system work again?

The reason I ask, is because luckily I bought a home warranty which will cover the repairs, and I would like to completely resolve issues with the system while still under warranty.

Thanks for any help

 

[Scotto]

Most likely your home warranty will fix just enough to get it working again and you usually have no say as to who will fix it and how.

At least that's my take on what I've heard about home warranties.

 

[weicm3]

Most likely your home warranty will fix just enough to get it working again and you usually have no say as to who will fix it and how.

At least that's my take on what I've heard about home warranties.

No. The first thing they will do is to find an excuse to deny your claim. That's what I experienced when dealing with AHS a few months back. I assume you have the same home warranty company?

If they sent a really good and honest contractor, you're in luck. But most of time, their contractor is helping them to get claim denied. Why? Contractors get more business from insurance company if they deny more claims. Contractors get paid more if money is directly from customer's pocket. That's why most of their contractors are not reputable local businesses.

Typical denial are like improper installation and lack of maintenance(they expect coil to be cleaned annually). The contractor they sent to my house even told me that our condenser isn't getting full sunlight and it caused excessive moisture to make system fail(what a BS).

Even they repair the unit at the end, you're still likely going to pay a good amount of money out of your pocket on top of service call fee. Things like permit, line modification(though it's really not required but they allow the contractor to charge it), and disposal are your responsibility.

 

[Designer]

Thanks guys,
I have kept great maintenance of the system, and made sure it was all in good shape before they came out to look so that there would be NO possible placement of blame on me. When I spoke with the boss after the inspection, he said he thought it was the compressor failing, as it is maybe 15-20 yrs old. He said they usually replace the whole unit on older models. So, I feel optimistic for now. They are coming out to test it sometime today. My warranty is through Old Republic Home Protection Company. Supposedly I only pay for the initial call fee, and other costs are covered by the warranty. But, we all know how that goes....

 

[weicm3]

Thanks guys,
I have kept great maintenance of the system, and made sure it was all in good shape before they came out to look so that there would be NO possible placement of blame on me. When I spoke with the boss after the inspection, he said he thought it was the compressor failing, as it is maybe 15-20 yrs old. He said they usually replace the whole unit on older models. So, I feel optimistic for now. They are coming out to test it sometime today. My warranty is through Old Republic Home Protection Company. Supposedly I only pay for the initial call fee, and other costs are covered by the warranty. But, we all know how that goes....

Hope it turns out good for you and keep us updated. I'm dumping my AHS contract. Also find it out on your contract. See if you're responsible for permit, disposal, and duct/drain modification on A/C claim.

It's weird that they couldn't find out if compressor failed or not on site when he was there.

 

[Designer]

Well, I have a feeling that the inspector yesterday was really just sent out to make sure that the claim was initiated through his company. So, the only tools he had with him were a set of hoses and gauges, and a temp sensor. He had hooked them up to two ports on the back of the compressor, I'm not certain what that did besides give him readings. I'm not familiar enough with it to know what is necessary to test the compressor....

 

[CraigFL]

Don't know where you are but Florida has some stupid environmental laws that require you to update to 13+SEER when you hava a problem and they won't allow you to just "repair" with a new higher efficiency compressor. Then, just to be sure you won't do it, they won't allow you to mismatch an indoor/outdoor unit.

 

[Demian]

Don't know where you are but Florida has some stupid environmental laws that require you to update to 13+SEER when you hava a problem and they won't allow you to just "repair" with a new higher efficiency compressor. Then, just to be sure you won't do it, they won't allow you to mismatch an indoor/outdoor unit.

The higher effeciency standards are federally mandated, not just FL.

 

[weicm3]

The higher effeciency standards are federally mandated, not just FL.

not true. you need to get 13+ SEER with R410 refrigerant only when you replace the equipment. if the old equipment is repairable(e.g. replacing the compressor), you're allowed to repair it. CraigFL was saying they're not allowed to repair old equipment in FL. which I doubt unless FL welcomes lawsuits.

 

[MrMack]

Hello everyone,
Yesterday I found out that I am fairly ignorant with respect to component interaction knowledge of the standard home a/c system. I have the standard system with the outdoor unit and the indoor furnace/blower. Long story short, the air coming out of the vents is not cold but the system still runs. The repairman yesterday said he thinks the compressor has gone out because the A coil is not cold at all, and the line pressures are off. He does not think the system is low on refrigerant. He had also mentioned that the TCV could be malfunctioning. So my question is: If the compressor has failed, would this have any downstream effects on the rest of the system (i.e. TCV), or would a replacement compressor (or whole outdoor unit) just make the whole system work again?

The reason I ask, is because luckily I bought a home warranty which will cover the repairs, and I would like to completely resolve issues with the system while still under warranty.

Thanks for any help

Get online and do some training about how the system works, determine if the compressor kicks off because it is too hot, if the compressor runs but don't cool, if the big fan on top is running, or if maybe a condenser, capacitor is shot or the freon is low. Have a competent HVAC tech to check it out with his meter and his gauges. Learn the lingo and watch what they do. A competent Tech will give you some options, study them ask about cost and don't get bilked....

 

[Demian]

not true. you need to get 13+ SEER with R410 refrigerant only when you replace the equipment. if the old equipment is repairable(e.g. replacing the compressor), you're allowed to repair it. CraigFL was saying they're not allowed to repair old equipment in FL. which I doubt unless FL welcomes lawsuits.

Yup, guess I need to brush up on my reading comprehension.

 

[CraigFL]

Sorry I wasn't clear... You can replace the compressor only but cant replace the whole outdoor unit like they used to.

 

[foss]

Get online and do some training about how the system works, determine if the compressor kicks off because it is too hot, if the compressor runs but don't cool, if the big fan on top is running, or if maybe a condenser, capacitor is shot or the freon is low. Have a competent HVAC tech to check it out with his meter and his gauges. Learn the lingo and watch what they do. A competent Tech will give you some options, study them ask about cost and don't get bilked....

what does it mean if it shuts because it is too hot ? is that a serious problem?

 

[MrMack]

Not for me. I know that it does it because it has a sensitive head pressure safety switch. I turn it off at the thermostat and then go outside and cool it off with the water hose. It only happens in the afternoons when it is over 100 degrees and the sun is shining down straight on the unit. Once an afternoon usually does it. I had to put in a new start capacitor in March and that is the first repair since it was new, in 1997. Be careful if you have the same problem, the hot water that comes out of the hose before it cools down can almost scauld you if it get's on you!

 

[Designer]

Well,
I just talked to the boss, and it sounds like they will try to replace the entire outside unit. He also mentioned requiring a new contactor.

The other thing he mentioned (...the upsell) was that with my 3 ton system, he could install a 3.5 ton outside unit for increased efficiency. However, this would require a larger A coil as well.

The other thing he said is that once you're going to upgrade the A coil, I could pair the 3.5 ton outside unit with a 4 ton A coil for even MORE cooling and that this would provide a larger magnitude temperature difference. To me, this increased coil surface area would seem to increase the convective surface area of the coil, but reduce the airflow area and make the fan work harder.

Now, I am not sure how I feel about this "hot-rodding" of the system. I have learned that there is always a catch, and also to trust the engineering that went into designing these devices. Do you guys think that his suggestions are legitimate?
He will be calling me with pricing later...will update.

Btw, CraigFL you were right, he hit me with the "Oh, you know they don't pay for disposal and freon recovery, right?"

Thanks for your information so far! At least it's not too hot here today!

 

[slopecarver]

Increasing the coil size will increase efficiency and make the fan work less hard (more area for the fan to **** air through. Too powerful of a system and you will be short-cycling, on off on off on off in a short period of time. This will cause extra wear on the machine and your utility bill.

Few years ago when I moved into this house the a/c wasn't working, everything would run but it wouldn't get cool. The guys found beads of solder in one of the devices, I'm thinking the expansion valve. Everything works perfect now.

 

[jay50]

Btw, CraigFL you were right, he hit me with the "Oh, you know they don't pay for disposal and freon recovery, right?"
Thanks for your information so far! At least it's not too hot here today!

Just tell him you will take care of the scrap metal disposal yourself. Call a couple of places that pick up scrap metal or maybe you can get a wino to take it off your hands so he can get another bottle of gutrott.

 

[MrMack]

Have you been told how much energy you will save with a larger unit? The truth about a unit cycleing on and off is true. The number of start ups of the compressor in a too large unit could very easily use as much power as the older smaller unit if the number of start ups is smaller. The needs of your house, climate, insolation ( heat entry) location of trees pavement ect. should be figured into the equation to determine the size of unit you need also will you need to increase the size of ducts, plenums, return air? Is the guy working on commision and wants to sell you a higher priced unit than you need? Actually how well did your 3 ton unit work? It will take a lot of hours of operation to ever realize any benefit for a new larger unit even if it reduced the cost of power to the A/C system to pay off the cost of a new unit only .5 tons larger.

 

[Designer]

Jay 50, not a bad idea....I think I'd have to get it approprately tagged that it has been evacuated or something?

MrMack,
No, I haven't been quoted any numbers. The guy was driving when I talked to him, so I don't think he could come up with them right then and there. Frankly, I think I would prefer a 1:1 swap out for tonnage. Mostly for the reason you stated. I would think that the difference between a 3 ton and a 3.5 ton unit is that the 3 ton might run a lower power for longer, versus the 3.5 ton a higher power for shorter, given that they are both cooling the same volume of house.

I think you're right that it is likely a bit of a play for him to make a little extra $. Not that that's bad, but I care more about my system being correct. The way I figure, a new 3 ton unit is going to be way more efficient than the old unit anyways.

 

[Designer]

Ok, So I just got off the phone with someone who knows this stuff quite well. He informed me that being in a very humid area, It is desired to have the a/c run longer in order to remove more moisture from the air. This is in contrast to a unit that will cool the air more, but leave the moisture in the air. So, an appropriately sized unit will be more efficient than what I had already, and run the proper amount of time to remove more moisture and cool the air correctly, whereas an upsized unit could end up drawing more power and cooling quicker, but removing less moisture.

Thanks everyone!

 

[jay50]

Ok, So I just got off the phone with someone who knows this stuff quite well. He informed me that being in a very humid area, It is desired to have the a/c run longer in order to remove more moisture from the air. This is in contrast to a unit that will cool the air more, but leave the moisture in the air. So, an appropriately sized unit will be more efficient than what I had already, and run the proper amount of time to remove more moisture and cool the air correctly, whereas an upsized unit could end up drawing more power and cooling quicker, but removing less moisture.

Thanks everyone!

You have talked to someone who knows his stuff. Keep his phone number handy for future needs.
Bigger is not better when it comes to home ac. Unit never runs long enough to dehumidify; the house will smell damp and musty with possible mold growth around lower floor mounted vents or curtains.

 

[IndyGarage]

This is correct about the size of the unit. It is possible to get more cooling for the same money by sizing up the A coil. Believe it or not, that's exactly what they do to get the higher SEER ratings for the newer equipment. The equipment isn't really any more efficient, just sized differently and controlled differently.

In fact, if you have to swith from R-22 to on of the "environmentally friendly" refrigerants, you will be using more energy, because the new stuff doesn't cool as efficiently - so they generally upsize the entire system to compensate. So much for environmental friendliness.

Your best bet is nearly always to fix the old equipment. A compressor can be replaced without replacing the coils, but they often replace the whole condensor unit, because it's a little cramped to work in there and it's a quickie job to replace the whole outdoor unit - it can be very profitable work.

There's really not much to an ac system. Two coils, a compressor, a metering device and a control system. You can easily tell if the compressor is pumping or not - all you need is a set of gauges. If the high side is lower than normal and the low side is higher than normal , and the machine is running, then your compressor isn't pumping well. If the high side and low side are balanced then the compressor isn't operating at all. Of course you don't know what normal is if your system isn't operating correctly. Mine runs about 85psi low and 350 high when it is working correctly - just for reference.

You don't need a certification to check the system. You do need one to do any repairs.

 

[Designer]

Thanks,
As of right now I am waiting for the contractor to find a replacement for the whole outdoor unit. Trying to find a 3 ton R22 unit and just keep the rest of the system the same.

 

[Falcon67]

Most likely your home warranty will fix just enough to get it working again and you usually have no say as to who will fix it and how.

At least that's my take on what I've heard about home warranties.

My daughter and son-in-law bought a $225 home warranty when they bought their first house. The ancient AC failed right off - which I told them to expect - and the home warranty replaced the entire system. I think they had to get two opinions on the system condition. Replacement parts were not available for the existing system. So - not all of the warranties are necessarily junk.

Glad you got hold of someone that got the the right info on AC in a humid climate. Bigger isn't always better.

Just tell him you will take care of the scrap metal disposal yourself. Call a couple of places that pick up scrap metal or maybe you can get a wino to take it off your hands so he can get another bottle of gutrott.

No - do not. You will be STUCK with the old unit until you have it properly evacuated, the compressor cleaned out/disposed of and/or and the unit tagged. NOBODY will touch it until then. It'll get evac-ed during the replacement but the compressor still has oil in it and if it's old, probably PCBs and other bad stuff. If you do find a clueless junkman, then great. Try getting rid of an old no-op fridge these days - you just about can't. Did one not long ago and I had to cut the compressor out of the box before any scrap yard would allow it on the place. No, I don't know what happened to the old compressor. I just sorta disappeared. I think the squirrels got it.
http://www.epa.gov/ozone/title6/608/disposal/household.html