Leaky Ducts, a Very Bad Problem

The most common place for duct leaks to occur is where the duct penetrates the sheet rock at the ceiling. The top photo is of one that is unsealed. I see ducts like this that have been sealed in other places including those subsidized by power company sealing programs.
Many people seal the least leaky areas and are therefore mostly just reinforcing the duct. If the average size of these leaks at the ceiling is 1/8 inch times the perimeter of the duct box and the average or small house has 8 ducts... This adds up to about 36 square inches. Imagine how much energy is wasted by a 6" by 6" hole in your A/C duct !

The right way to do it is to dig in the insulation and expose the leak first. Then seal with a latex based sealant that has fiber in it. as shown in the second photo.

DUCTS IN THE ATTIC???

DUCTS IN THE ATTIC???

I was reading an article titled "Ducts in the Attic? What Were They Thinking?", and it caused me to think about the merits and shortcomings of this practice.

The article was presented at a conference about common building practices and air conditioners and much of it is technical and way too detailed for anyone outside of an engineer, builder, or air conditioner contactor.  That being said, there are definitely strong arguments to made for not having ducts in the attic. 

The article explored the impact duct location has on cooling load,  peak demand, and energy cost in hot climates. They studied climates in Houston, Phoenix, and Las Vegas.

Tampa, FL is probably similar to Houston in humidity and temperature. For an average new home in these climates, they concluded that locating ducts in the attics increased the cooling load significantly, which increases cooling costs and ultimately demand.  Which means bigger carbon footprint.

My house is already built and my ducts are in the attic! What do you expect me to do?  Rip my house apart? Have ugly ducts hanging from my ceiling where I can see them? I won't live long enough (even if I live to be 100) to recoup the costs of refitting my central air conditioner ducts running through my hot as death valley attic!

The perfect time to change this practice is when the house is being planned and built. But for most of us, that ship has sailed.  Let's explore options for the home that is already built and lived in.

All ducts are leaky  We do not want heat exchange in the attic, that is we don't want the cold conditioned air in the ducts to be leaking into the hot, unconditioned attic. One way to reduce the heat in the attic is to use isynene spray foam. It is sprayed onto the underside of the roof.  It is like a layer of insulation on the ceiling of the attic.

If you are really concerned with not losing any conditioned air in the attic and you do not want to have exposed ducts in your air conditioned living space and lowering your ceilings and generally retrofitting your home is out of the question you may  want to consider ductless systems, also known as mini-splits.

Mini-splits have no big, dirty, leaky ducts to deal with. Because of the absence of ducts they are extremely efficient and cost effective to operate.

 A mini-split system could be the perfect solution for those of us in homes with difficult to change ducts in the  attic.

Integrity Air Conditioning would love to discuss your needs and concerns regarding cooling choices.

Call Jay at (813) 932-2665

You want your Air Conditioner to outlast your neighbor's?

Of course there are no guarantees; machines sometimes fail no matter what you may or may not do, but odds are in your favor if you implement a few basic steps.

The first step is the easiest and most important:

1.Change your filter! Get in the habit of doing this on a regular basis. The purpose of the filter is too keep airborne junk away from the inside of your air handler, where it can clog the coil and reduce air flow. Dust, dirt, pet fur, etc are all enemies of your A/C unit.

2.There are things you can do outside too. It is important that bushes and landscape plants near your outside condenser unit do not grow too close and and suffocate the unit. It needs lots of airflow to operate efficiently. Trim any bushes and plants so they are at least 18 inches away from the unit.

3.If you have a dog, of the male variety do whatever you can to discourage him from marking (urinating) on the A/C unit. This is very bad for the unit. You may need to put up a fence protecting your unit if your dog persists in peeing on the unit.

4.In Florida we most likely use our A/C units throughout the year, since our summers last forever, but it still good to check and make sure nothing is blocking your vents, such as curtains, furniture, artwork, etc. Remember, your A/C needs lots of airflow!

5.With our current rainy weather that Tampa is experiencing is it important that insects be controlled. Ants are notorious for sabotaging the electrical contacts of your outdoor unit. Poison them with an ant killer bait. Pest control companies often use perimeter granules.

6.Be nice to your A/C unit by providing regular maintenance by a professional technician. Despite your best efforts your coils could be dirty and need a good cleaning. Don't wait until it is broken. Call today and schedule a tune-up. Integrity Air Conditioning can be reached at (813) 932-2665

Some ways other companies oversell new air conditioning systems.

1. Coil with normal rust

2. Coil with hole that allows air to blow through

The tech./ salesman shows it to you and asks “what do you think of that? “   Many customers respond with “that looks bad” or “is that bad”?

Truth is that it looks worse than it is.  The steel plate on the end of the coil...called a tube sheet is not critical... if it mostly rusted away it is not likely to be a problem because:  behind it is an aluminum fin that would keep air from bypassing the coil.

Their claim:  “The average life of air conditioners is 8 years”.     The truth:  ASHRAE... the engineering association of air conditioning collected info that says that the average life of heat pumps is 12 years and the average live of air conditioners with electric heat is 15 years.  Same for a gas furnace with an air conditioning coil on top... average 15 years.       My statement:  I see a wide range both sides of average.   When a system is near 10 years old or more  I would be reluctant to put much money in repairs.   And systems that have many repairs are not like new,  but rather, had a hard life.

The second photo shows a potentially problematic rust hole.  The rust hole at the bottom left of that coil might allow air to bypass the coil and splash water out of the drain pan causing a water leak.   For that customer the water leak problem went away when we cleared the drain pipe.

Jay Hoover,   Integrity Air