Top 4 Things That Interfere With Central AC

By Carl Seville, Networx

Plenty of people who run central air conditioning systems in Houston (and other cities where hot weather dominates the calendar) complain about how their air conditioning doesn’t do a good job keeping their home comfortable, and, in most cases, they are probably right. There are so many things that can and do go wrong with central HVAC systems that it’s tough to know where to start, but I’ll give it a shot.

1. Leaky ducts

Probably the single biggest cause of poor AC performance is leaky ducts. Ducts are kind of like pipes – they move air through them and deliver it at the end. We notice when our water pipes leak because we see the damage immediately, but we rarely see the effects of leaky ducts directly; rather it sneaks up on us over a long period of time, and many people never figure it out. When ducts leak, they let cool air out into whatever space they are in, often the attic, which, in case you haven’t noticed, can get pretty hot in the summer. Ducts need to be sealed at all the metal-to-metal and metal-to-flex connections – not at the insulation. Have someone pull back all the insulation and put a nice thick layer of goopy mastic at all the joints, then replace the insulation. Don’t use duct tape. It won’t work, and the metal tape designed for ducts doesn’t do a whole lot better.

2. Too much or too little refrigerant charge

Something else that can make your AC inefficient is the refrigerant charge. Traditional AC uses a refrigerant that transfers the heat between the inside and the outside. Every system is designed to work efficiently with a specific amount of refrigerant, and too often there is either too much or too little in the system. A good HVAC contractor can check the charge and either add or remove some to make sure it is set correctly. A wrong charge can decrease the efficiency by 20-30%, so checking and fixing this can make a big difference.

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Disclaimer: The views expressed above are solely those of the author and may not reflect those of
Care2, Inc., its employees or advertisers.

Teresa W.

4:47AM PDT on Sep 24, 2012

thank you

September 24
send a green star

Dale O.

8:24AM PDT on Jul 31, 2012

Ontario summers are hot and humid, two weeks ago the thermometer hit 108, ouch, have to have an air conditioner or my 16 year old blind cat that owns me will take out a contract on me as she wears a thick coat. As long as I supply her with love, food, water, vet care (sorry I said that word), air conditioning in the summer and heat in the -40 winter, my existence is secure. But if I lose the A/C or the catnip...

July 31
send a green star

Jeramie D.

11:42AM PDT on Jul 9, 2012

Thanks

July 9
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Sue H.

8:58AM PDT on Jul 9, 2012

Good to know information, thanks.

Dana W.

11:23AM PDT on Jul 8, 2012

Thank you for the suggestions. I had one house where one unit was actually installed BACKWARD, so that the airflow had to make a U-turn so that unit wasn't as efficient. Also there is some laziness on the part of builders; when your ceiling vents are open look at the direction they're facing. Some of mine where screwed into the ceiling facing away from the center of the room so that the air blows into a corner.

July 8
send a green star

Sue M.

8:18AM PDT on Jul 6, 2012

thanks

July 6
send a green star

Duane B.

11:09AM PDT on Jul 5, 2012

Thank you for sharing.

July 5
send a green star

Mukesh R.

9:35AM PDT on Jul 5, 2012

thanks for sharing....

Sandi C.

8:24AM PDT on Jul 5, 2012

Thanks for sharing!

Terry V.

5:24AM PDT on Jul 5, 2012

Hose off the outside of your central air unit.
For filters, check instruction for the type or have your blower adjusted for using a higher grade filter.