House doesn't cool down enough

[Deno]

We had the same problem here in Mississippi. The duct system on the home (28x64) was shifted a little and even after attempts to fis the problem with duct tape it still leaked too much air therefore the air was working way to hard to try and cool it. We had a friend of our put a regular house duct system under the home. They just slid the old aluminum ducts over and built an duct system to the existing vents in each room. They built a state of the art system where each duct was the size needed to get the same amount of air needed to cool each room evenly. It was a God Send. Our power bill dropped $50 and we are cooling our hills now. Good luck to ya.......

[Jackie]

Thank you again for responding! We really appreciate all of your input.

After reading everyone's enlightening posts, we think we're going to try awnings on the south and east windows, plus and an awning over the outside condenser unit, which is on the ground in our home. (One additional awning will not make or break the bank.)

We'll keep our fingers and toes crossed and see how that works. Hopefully it will be much better than what it is presently.

Setting the thermostat just 30 degrees below ambient is not a reasonable option for us. That would mean when it is 115 deg we should be satisfied with an 85 degrees and when it hits 125 deg we should be satisfied with 95 inside. Nooooo!. We moved to AZ from TX, where it also can get brutally hot. (The big difference is it didn't routinely hit - and certainly never sustained 125 degrees, and it is quite humid too.) We never encountered this problem before coming to AZ and we were always able to keep our home at a comfortable level of 70 degrees year-round.

We're still thinking about that evaporative cooler, for the months where it is hot and dry, but like I said before, we can't do multiple things this year - just one - and so it's the awnings for now. Besides, I am still concerned about that one a/c guy who said the moisture from them would rot out our home. Does anyone know anything about them?

Thank y'all again.

[rmurray]

Everyone I ever met from your area said..."its a dry heat"...Somehow in their mind it makes it bearable..Properly sized a/c units are only meant to cool the home 20 to 30 degrees from the outside temperature...but for us in a humid climate...that is enough because they also remove the humidity form the air making it much more comfortable...You might be fighting a never ending battle...It will take a few years to acclimatize your body to the conditions..I doubt you will be able to cool your home to 70 degrees when there is a long spell of 125...If this is totally unbearable you might have to consider moving again...

[Janie]

I've lived in AZ 18 years and the highest recorded temperature ever was 122 in June of 1990. Where you get this 125 is beyond me. Hasn't even come close to 122 in years, maybe every other summer you might see 116-17. Average is about 105. A really hot day is 110-12. And it never lasts for more than 2-3 days. I keep my AC at 83 in the day and 78 at night. 83 feels very cool when it's 105 outside. I have 2200 sq feet and a 5 ton heat pump. My highest bill last summer was $285 in August when the humidity was high because of monsoons. Try 83, you'll be surprised how cool it can feel. I'd be wearing jeans and sweaters at 72.

[Jackie]

I stand corrected by 3 degrees.

A neighbor had said to me something to the tune of: If you think it's hot now, wait 'til it hits 125. Had I been posting on a meteorology board, I would have taken the time to investigate what the precise recorded high temperature was prior to repeating that number. Then, had I an attitude similar to yours, I would have called him and challenged that he was off by three degrees. For all intents and purposes, I don't know that we would notice a difference between 122 and 125 anyway.

I'm very glad you are comfortable at 83 degrees. We are not. That is why we posted our questions here.

[Janie]

You need to be more realistic about the average summer temperature in central AZ, and what your AC unit is capable of doing. Talk about an attitude.........

[Anne]

Jackie - you haven't said whether your house has 2x4 or 2x6 walls. If you have 2x4 walls there just may not be enough insulation against the heat no matter what you do. Most people think of insulating against the cold and don't think about summer heat. You could try moving the AC unit to the shadier side of the house. In any case, I would plant some fast growing trees to help shade the house. Fast growing trees aren't always the best but it would help. Even a lattice screen would help shade the AC unit. Good luck.

[mac]

Ah, you'll get used to a bit of heat Here in the rainy Northwest, we say the first winter is a curiosity for most people (38 straight days of rain) - the second one determines whether the person is a true Northwesterner.

A dry 83 inside sounds survivable over time. Or maybe it's because we won't see 83 OUTSIDE for another few MONTHS

Good luck! Poplar trees grow quickly but play hell with sewer lines.

[Tommy]

We live in Mississippi and are having some cooling/heating issues in our home, too. Our house is approximately 2000 sq. ft. and we have a 4 ton unit. I would like to know in what area of Mississippi you are located and the name of the company that fixed your duct work. Thanks for any information you can provide.

[Tim]

One major problem many people (and set up companies) miss is moisture migration. Moisture migration occurs when the air inside your home is less wet than the air outside. The little droplets are crowded in the outside air and are looking for a less crowded place to exist (sort of like moving to the suburbs!) inside your home. The most substantial area of this migration is through your floor! This area is where you need to focus.

The plastic membrane that covers your home's underbelly is not a vapor barrier. In fact, the installation is very specific in stating this because it is not intended to a vapor barrier. What the installation manuel recommends is a ground vapor barrier- usually of at least 6 mils- to be laid down completely covering the ground beneath your home. Installers don't like to mess with putting this down because its tedeious. However, many home builders will void the warranty for moisture related problems if this vapor barrier is missing!

My suggestion is to put a vapor barrier down under your home. Without this vapor barrier, your home actually becomes a huge upside down plastic container. (If you have ever turned a plastic container upside down outside on a warm day you know whaat I am talking about.) And actually traps this moisture inside. As your ac unit is working overtime, more and more moisture is moving into "the suburbs" of your home.