Air Conditioning Problems

[LovingSAT]

Originally Posted by the_dimwit

Before you call someone to come out and take a look, check the following:

1) Airflow - reach your hand up to one of the air vents and see how much air is coming out; also check to see how cool/cold it is. If there is very little air or the air that is coming out is warm/room temp, you may need to call someone.

2) Filter - make sure the filter is clean and free of major debris. If it's dirty, replace it and see if airflow increases.

3) Coil - sometimes, when an AC system is pushing really hard to keep up with outside air temps and inside humidity, the AC coil can "freeze up", meaning ice collects on the coil and prevents airflow/cooling process. You can verify this by first placing your hand on the outside of the unit (inside your house)--if it's really cold or there is condensation on the outside of the panel, you likely have a frozen coil. Turn your unit off, open the panel, and allow the ice to melt away. You can expedite melting by using a hair dryer (6-12" away from coil, warm setting only).

If none of the above works, you'll likely need to call someone out to do a health check as you may be low on refrigerant.

--Dim

And be sure your filter is in the right way.

[KM1174]

Originally Posted by Mom2Feebs

I can't believe no one here has stated the obvious.

If it's 100*F outside in the afternoon, your A/C, at best, is only going to be able to cool your house by about 20*.

By setting it at 72*F, you're going to burn it out or freeze it up.

brb LOL'ing at this poster.

ok done with laughing.

i have to disagree though. the insulation in my new house is AMAZING. when it was 105 a few days ago, my house was steady at 77F. AC barely turns on.

Originally Posted by Mom2Feebs

Really? Huh. Guess all these sources are incorrect:

AC won't cool below 79 degrees!! (specifically post #6)

Big-homes-mean-big-air-conditioning-bills - Southtown Star

Central Air Conditioning | Ask the Builder

Air Conditioners In 100 Degree Indianapolis Heat | Homesense Heating | Cooling - Indianapolis Air Conditioning Installation


And, actually, yes, you can freeze up your A/C by constantly running it. Hello? It happens all the time!

actually, yes, all your blogs are wrong. i can create a blog to say whatever i want also!

ps - to the OP: your AC might be too small also.

[lollygagger428]

WOW is about all I can say to SA weather...our second summer here and this year is doing me in. We keep our a/c at 76 and I'm just waiting for it to explode outside my window. I saw today where SA is the 6th hottest city in America; THIS I believe.

[jasonamd]

Originally Posted by Mom2Feebs

I can't believe no one here has stated the obvious.

If it's 100*F outside in the afternoon, your A/C, at best, is only going to be able to cool your house by about 20*.

By setting it at 72*F, you're going to burn it out or freeze it up.

Actually, part of this is kind of true. With a system designed to the specifications for the area it is in, it is entirely possible to not get below 80 when it is 100+ out. Not sure about San Antonio as it has been several years since I've lived there, but in Houston the design temperature is 98 degrees. This means that when it is 98 degrees outside, the system is designed to cool the home to 78. This of course means if it is over that, it probably won't get to 78. Also, at the design temperature, in this case 98, the system will run continuously to keep it at 78. If you are able to get your home in the low 70's when it is 100+ out you have an oversized, inefficient system. Most systems tend to be a little oversized so you may be able to do better than 78 when at the design temp. Also the 500sqft/ton "rule" about sizing a system almost always will result in a incorrect system size selected. I have a 2000sqft house and a 3 ton AC that works just fine.

Now as far as the statement of burning it out or freezing it up if you set it to 72...that isn't even close to being true. Only time a AC system will freeze up is if there is something wrong, usually low on refrigerant. Also, a AC system would actually last longer if it ran continuously. More stress is placed on the system by cycling on and off than by running all the time.

[Hedgehog_Mom]

Yesterday my AC was turned off all day and the temperature inside the house only reached 85. I guess the insulation and the radiant barrier really do help a lot. So if the best my AC could do was 5 degrees cooler than the house would be without AC, I wouldn't think it was working very well.

[88txaggie]

OP - all advice about ac systems are good here, so won't add to that. But cooling also depends on which way your dwelling faces and whether you have shade trees. Also, an attached garage with a room above will have trouble cooling in the summer. Our old house in Plano was east/west facing; we had 2 story entryway windows that faced the afternoon sun. There was NO WAY to cool that house. In addition, the master bedroom was over the garage. We did all we could - solar screens, re-ducting...etc. But there was no way for the ac to keep up in the summer.

Lesson learned, we bought a house that faces n/s and has shade trees. Much easier to maintain a comfortable temp in the summer.

[jasonamd]

Originally Posted by Hedgehog_Mom

Yesterday my AC was turned off all day and the temperature inside the house only reached 85. I guess the insulation and the radiant barrier really do help a lot. So if the best my AC could do was 5 degrees cooler than the house would be without AC, I wouldn't think it was working very well.

Not really a good example as your house will not stay at 85 without AC during this time of year. Leave it off for a few days and see if it is still 85.

If I leave my AC off for a day it will get to around 87 inside when it is in the upper 90's. A couple years ago when we had a week of 100+ temperatures, my AC could maintain about 77 when it was 105 outside and it would run continuously to do so. And that is well within what is expected of the system, a little better than what is expected actually.

The longer an AC runs the better. If your AC isn't running for at least 15 minutes at a time during peak heat it is oversized and wasting energy. An AC won't reach peak performance until it has been running for around 10-15 minutes.

[TexasRedneck]

Another consideration is the old suggestion that you "set back" the thermostat during the day while you're away at work. What they fail to take into account is that as the house itself warms, so does everything else - walls, furniture, etc. When you set the thermostat back down, the system has to cool everything back down again. Don't recall the exact numbers, but the actual "savings" were so nominal that we just left ours set to the temperature we wanted all the time.

Sometimes we can be penny-wise and pound-foolish.

[jasonamd]

Originally Posted by TexasRedneck

Another consideration is the old suggestion that you "set back" the thermostat during the day while you're away at work. What they fail to take into account is that as the house itself warms, so does everything else - walls, furniture, etc. When you set the thermostat back down, the system has to cool everything back down again. Don't recall the exact numbers, but the actual "savings" were so nominal that we just left ours set to the temperature we wanted all the time.

Sometimes we can be penny-wise and pound-foolish.

Last summer I actually did a test with this. For a week I had my AC set to 80 when gone, 76 when home and monitored the daily power usage. The next week I just left it set at 76 all the time. There was basically no difference in usage. I have had it just set at 76 all the time now...unless we are gone for a few days then I will raise it up a bit.

[dpantle]

The power consumption reports on utility company websites are very useful. I've used PEC's for a few years now, and I came to the same conclusion as jasonamd.

We have a zoned A/C system. Our kids rooms, game room, and utility room are on one zone, while the rest of the house is on another. We leave that system off since the kids have left. We built the house with that in mind. We only run that system when we have guests. I now know how much to charge guests when they stay.