Why do my inside and outside A/C units run but my house is hot?

Question

I have a brand new 3 ton unit. (house 1350 sq ft) I had all my duct work replaced. Both inside and outside units run but my house is very hot. There is R 30 insulation in the attic, too. I need to be cool and stop wasting electricity. Help please.

My unit was installed in May. I have had the people out 3 times. The unit runs constantly (translation - huge electric bill). In the afternoon it is 86 degrees in my house with the unit running. The unit is a heat pump. Should the copper line be hot or cold? Should warm or hot air be coming from the condenser?
I have considered some kind of reflective material on the inside of the roof. My house is old and there is no insulation in the walls (stucco and lathe). It is not a slab foundation.

Answer 1

you said that your house is old and that there is no insulation in the walls, the hot air is coming in through your walls,the unit should have been sized bigger due to no insulation in walls,the inside and outside units are supposed to run together,close all your shades and curtains during sunny days this keeps the sun out.you should have spent the money on the insulation first than gotten the ac,they have what called spray insulation for walls,you will be losing a lot of heat during the winter,you need to get the walls insulated.

Answer 2

How new is your AC?
Was it installed in the winter?
Had it been working before?
If it hadn't been used before you just call the people who installed it back.

Have had it for awhile.

Have you checked the outside unit to see if the fins are plugged? You may be able to just use a hose to spray the unit to clean it. Is it in a real hot area? If the outside unit is in the direct sun it will not work as well as it should.

Have you changed the inside filter? If it is dirty it can cause the coils to freeze up. & you don't get as much cool air.

You must test the temperature for accurate readings.
You can just say your too hot.

Is air coming out of your vents?
Now days they are installing air mixing shutters in the vent pipes that let you mix the flow of air. You would change the settings for different seasons.Do you have something like that?

Is it cold air, or is it room temperature?
Because the air from all parts of the house gets mixed extra heat in one area can cause others not to get as cool.

Are all doors & windows closed?

Are you running it long enough? You can't turn it on in a hot house & hope to have it cold in minutes. Turning on the AC in the heat of the day will take longer to cool down, because the heat gain is high at that time,

Is the thermostat near a vent? It could mean that it will cool that area & would shut down too soon.

You could try to leave the fan on all the time. This would help to mix the air better & have a more even temperature through out the house.

This isn't in the best of order but you should be able to get an idea of things you can check.

Answer 3

That is a tough question to answer with the data given.
Something is seriously WRONG!
If it was recently installed and still under warranty I'd IMMEDIATELY call the installers and have them repair the unit.
A three ton unit is too large for a small and well insulated house. 2 ton maximum for a house like yours. Anything larger is a waste of energy, will "short cycle", and will never lower the humidity to a comfortable level.
You should NEVER have hot air being discharged into your living area if the system is operating properly.
If you mean the house is not comfortable, but the unit is working correctly, then it is because the unit is TOO large.

Answer 4

I,myself,live in an old house. I installed a three ton in my home. My house is pier and beam and also not insulated in the walls. You need to stop the radiant heat from permeating your windows by using dark curtains or blinds. Set your thermostat at a comfortable temperature.The heat from the condensor should be hot.The copper line with the black insulation should be cold to the touch.The other copper line should be hot. While I was in college,I was told by my instructors to stay away from heat pumps as they were a pain in the ***. I still repair them at work ,but when the chance arises,I replace it.

Answer 5

Insullation in the attic is not going to help you too much when trying to cool your house. Heat travels up real well but not down so well. If I was you, I would have my exterior walls insullated (they sell ones that also reduce noise as well as insullate thermally).

Does the air come out of the unit cold?

Answer 6

3 tons does sound very large for a 1350 square foot house unless you have a lot of large windows; especilly south and west facing.

Make sure all the windows, doors, and other openings are closed.

If you have large south and west facing windows, close the curtains in the day to help prevent heat gain. Heat gain is the greatest on south and west facing windows. The same goes for skylights. If you do not have good curtains, invest in lined curtains with a white liner that will face out.

Getting another opinion is worth the cost.

Answer 7

I think you have to insulate the walls the attic is fine you will save the cost of insulating in reduced electric bills over a period of time. I live in FL and most power companies will evaluate your problem for nothing.Who knows more about power use than the power company give them a call.

Answer 8

Try a attic fan first. Then a ridge vent or cool-ply decking, a/c probably won't cool more than 20 degress more then the outside temp. You have plenty of tons of a/c. You have to take heat out of the attic.

Answer 9

If this unit is "brand new"
surely you have a service warranty (??)
what's up with not calling the company that installed it
and getting an up close and personal read out on why
the damned thing isn't performing ??

Answer 10

Sounds like you don't have the proper amount of freon in your system.

I would call a hvac (a/c contractor) contractor, Not the one that installed the new unit. and Get a second opinion so to speak.

But, I am willing to bet you are low on freon, or they overcharged it with freon...

Good Luck, !!!!!!!!!!!