Central air conditioner not cooling house?

Question

We live in the country in KS. We have no shade trees. Our home is a double wide manufactured home on a permanent foundation. It doesn't have high ceilings, and only 1 floor. The problem is the house gets hot during the day even though the ac is running. At 9:00 p.m., it is still about 82 degrees in here. I just think the AC isn't working quite right. Any suggestions?

I appreciate all the advise. I thought I'd add some additional details:
1. because we are out in the country, we have taken in a number of stray dogs and cats. They are indoor and outdoor animals, so lots of shedding. So, we change the air filter very frequently.
2. Great info on the freon lines. Husband went out, small line was warm not hot, and large line has small amount of frost on it.
3. We are planting trees this fall.
4. We will go get lattice to make a shelter for the unit.
5. House is about 16,000 sq ft. Have to search for info on size of ac.
6. Put thermometers against 3 vents. After 5 min, temps are: 60, 60, and digital says 70.1, but may take longer to register, it doesn't go down into the vent

Any other recommendations will be appreciated. THANKS!

Answer 1

If you believe that the air is moving sufficiently inside let's check the outside unit.
1. First feel the air coming out of the unit. You should feel heat being removed from the house.
2. Next look at the 2 freon lines - there will be a big one and a little one. The little one may be very hot so be careful. The big one is the low pressure side and on normal conditions where the pipe is exposed should be cold a sweaty.
From this big line you can tell alot.(you will have to find a place where the insulation is off or right where it goes into the outside unit)
3. If it is frosted up then go to 4 if not go to 5.
4. This could be due to either insufficient air flow across the coils of the inside unit or low freon which will cause the coil to start freezing.
If there is frost, cut the unit off at the thermostat by switching the heat/cool switch to off and turn the fan switch from auto to on. This will cause the fan to continue running and turn off the compressor outside. Leave it this way for a minimum of 30 minutes. See if you notice the air flow to improve coming out of the vents. While it is off you can check your air filters and make sure they are clean. Replace if necessary. Later turn the A/C thermostat back to cool. Notice if it cools better and monitor the big line. If after about five minutes the line is cool to cold then the freon level may be OK and you should feel hot air coming out of the unit. If it is only barely cool or not cool the unit is probably low on freon.
5. If the big line is not cool and the little line is not warm then either you are very low on freon or your compressor isn't running. Either way you will need to get an AC repairman for repairs.

Answer 2

Well, I would first ask you the square footage of your house, then the size of your central air. It could be as simple as undersized.

Second, if everything is sized properly, the next question would be, "do you wait untill it is already hot in the house before turning on the central air"?

There are many reasons a central air could loose capacity. First would be a dirty condensor. (the unit outside) Yard debris ectra...can clog the fins of the condensor and make it have to work a lot harder. I would suggest having a profesional clean it properly. Second, the unit could be low on refrigerant. If that is the case the suction line (the big insulated copper line) will start to freeze up outside by the unit (if ran long enough). This too would require a service tech.

Third, check your furnace filters. It it is a manufactured home, it will have either a coleman or intertherm furnace in it. Both furnaces have their filters in the doors. This is something that should be cleaned monthly (as the text book says).

Fourth, make sure ALL vents in the house are open. Even if you have a bedroom that no one uses. The heating/cooling system is designed to cool the whole house. Make sure furniture and rugs are not blocking any of the vents.

Fifth, it could be that the compressor is becoming weak. When this happens, high pressure will leak into the low pressure side of the air conditioner, causing the temperatures to rise. This will require a new compressor or new condensing unit.

One quick way to check your a/c is to put a good reliable thermometer into a vent while the a/c is running, give a some to measure the temperature. If everything is working properly, the vent temp with your a/c on should be around 55 degrees.

Basicaly, if it is more than dirty air filters, your best bet would be to call a service tech. It may be spendy, but it would sure beat sitting in the heat. Hope this may have helped you.

Answer 3

Air Conditioner Not Cooling

Answer 4

Hello Nancy:

Two easy things you might try is to replace the filter and clean the indoor and outdoor coils. I've seen this increase the efficiency of systems by 50%.

To find out if your central air unit is working properly, turn the system on and take a good thermometer (I use a cooking thermometer) and place it in the return vent (the vent going to your furnace). Give it a few minutes, then write down the temperature. Then go to a supply register (one that supplies air to the room) and place the thermometer there for about five minutes. The air coming out should be 16-20 degrees cooler than the air going in. If it is 15 degrees or less OR 22 degrees or more, you have a problem that will need to be handled by a pro. If you have a good temperature drop, the system may be undersized; you will want one "ton" of cooling capacity (12,000 Btu) per 900 sq ft of floor space. (In KS, you may want 1T per 700 ft2.) Other than replacing your system, you could add a wall or window mount unit on the south side of your home.

Can you plant some poplar trees and other deciduous trees on the south side of your property? They won't help this or next year, but after that...

Answer 5

If your house is closed up tight there's no reason that a good central air shouldn't be able to maintain a temp of around 72 degrees.
Might be time for some service....have you changed the filters recently?
Might be worth having a professional come in to take a look at it..the money you spend you'll save in the electric bill since I doubt your unit is shutting off at all...also, you'll be a lot more comfortable.

Answer 6

You can rinse out the condenser to help it work more efficiently. If it's pretty old, it may have leaked out some freon, but that would require calling in an inspector.

Hey though, why don't you get some shade trees, and better curtains to at least make the AC's job a little eaiser. I'd imagine that if it's only getting up to 82 that it's doing something... just not quite enough.

Answer 7

It could have frozen up because it's low on freon.. Turn it off for a few hours (or overnight) and see if it comes on and cools properly in the morning. It will freeze up again eventually and begin blowing warmer air (if this is the problem), so you will still need to call the A/C guys and have them come and charge the system. Hopefully your leak isn't large enough to warrent major repair this year.

Answer 8

Aside from the usual factors(blocked vents, especially cold air return, dirty filter, unit low on freon, etc), The scenario you described is quite common. No shade, hot sun,and mobile homes are notoriously hot. I bet the A/C unit came with the home package. Dealers like to cut costs as much as possible, and your unit is just not quite big enough to do the work load placed on it. Ask your local utility if they do an energy evaluation, most do for free.

Answer 9

Ac Not Cooling

Answer 10

The number one way to help the AC cool your house is for you to help cool the AC. With the absence of trees, the next best thing is to erect a structure over the AC. Use large-hole lattice work. However, make sure it rises at least 3 feet above and around the AC structure to allow for the AC to breath and remove the house heat. Do NOT cover it with anything solid: the AC needs to breath. The drop in temperature inside the house will be especially dramatic if the AC is presently located on the South or West side of the house.