Tuesday, March 23, 2010
Solving air flow problems in your home
Basic things that the homeowner can check to help air flow:
First and foremost, check your furnace filter to see if it is dirty and if so, remove the dirty filter and install a new furnace filter. Plugged furnace filters restrict air flow by creating a pressure drop. Next, walk around your house to see if any cold air returns have anything such as couches, rugs or cabinets obstructing the vent. If anything is obstructing the vent, then remove these obstructions so that the cold air return, which is an air intake, can draw in enough air. Last, but not least, walk around your home to check to see if all supply registers (heat vents that blows out air) are open. All supply registers should be open. A popular homeowner misconception, is that by shutting off certain vents throughout the house will cause other vents to blow harder. This simply is not true, because CFM (a measurement of air flow, cubic feet per minute) is determined by the pipes diameter and only so much CFM can ever blow out due to the size of the round, regardless if other registers are shut off or not. Shutting down too many supply registers usually causes more harm than good by creating pressurization problems with the overall duct system, that in an extreme case can actually cause your furnace to short cycle on a high limit and hence increases the cost on your utility bill while working key HVAC components and parts to reduce their life expectancy. Never buy and install heat vent filters either, because these filters really cause pressurization problems too. If there is too much dust blowing out of the vents, then the best thing that you may consider is to have the HVAC system cleaned out thoroughly with the power vacuum/air sweep method in air duct cleaning by an ACCA (Air Conditioning Contractors of America) member company. An average price for a 1 furnace home would cost between $400.00-$700.00 to do the job correctly, depending on where you live in the country and depending on the service providers cost to operate.
Some solutions that an HVAC company or contractor may suggest:
Very often in older homes, air ducts are sized incorrectly due to building departments in the past not emphasizing the importance of properly sized air duct construction and the by the fact that the builder wanted to save a buck to construct his own duct work rather than paying a heating and cooling professional to install the duct work properly. In recent years, many building departments throughout the United States really have zeroed in on enforcing proper duct design, so in most newer homes indoor thermal comfort has improved drastically. Some of the things that your licensed HVAC company or contractor may suggest to you to drastically help your older homes air flow is as follows:
Let me tear out all of your ducts and start over! (That would be sweet, however in many instances that is just not practical due to cost, time and a big mess!)
I can band aide your homes HVAC system by replacing your old inefficient furnace with a Rheem 80% AFUE 2 stage variable speed furnace equipped with the GE ECM motor. Visit www.luckyduct.net to learn more about the GE ECM motor. The GE ECM motor operates 30-40% more efficiently than a standard conventional multi-speed motor and sustains constant CFM even if your duct work is undersized and restrictive. What this means is that vents that seem to never blow air with your inefficient old furnace will all of a sudden blow air after the new Rheem furnace equipped with the GE ECM motor is installed.
For some reason your home does not have enough return air openings to even allow enough air to enter the duct system at all! We need to build additional return air openings into your duct work so that we can get additional CFM into the HVAC system so that your AC indoor evaporator coil can stop freezing. Good golly, you're paying more money on cooling not to mention the fact that your AC doesn't even keep your house cold enough! Let's fix that and add some new return air openings so that you can save some money on your utility bill and actually cool down this summer too!
Let's go ahead and rip out the 4" diameter supply runs and install 6" diameter runs so that we can circulate more air into that sun room!
You know, your ducts amazingly enough are sized correctly, but all of the air is escaping into unfinished portions of the house because the construction of the duct work is very loose. Let's go ahead and seal up every trunk line connection, branch line, and all the end caps with mastic duct sealant. By sealing up every duct connection on the entire system we'll see if we can blow those curtains side ways after all! No, just kidding, but the air will come out a touch harder, though as a result in sealing up the duct work better and you will see a significant reduction in your utility bill because the system will only cycle half as often now.
You know, for some reason all of your duct work is sized correctly, but the return leg that is attached to your furnace is severely undersized and is acting like a choke point. Lets rip this leg out and install a bigger one with a greater dimension!
You know, your home builder really got cheap and should have installed 2 separate systems considering that your home is 3600 Sq/ft. Two smaller systems will actually cost you less on the utility bill to operate and will provide greater comfort. Save up some money and lets build that second system in the attic!
You know, the most cost effective thing that I can think of that will improve your indoor comfort tremendously is to simply just zone your current system so that 3 different thermostats will control 3 different temperatures in your home. Aprilaire and Honeywell make great zoning systems and we usually can get this system installed from $3800.00-$6,000.00 depending on how fancy of a system you want to have installed!
You see some of these band aide jobs will cost just a few hundred dollars, while some solutions may cost a few thousand dollars, but in the end after the corrections are made, your utility bill will probably reduce a bunch and you'll finally have true indoor comfort that you didn't have before. Many HVAC companies and or contractors will give you more than one option to consider as well so that no matter what you decide on some sort of indoor air comfort solution will be achieved to at least improve the comfort situation. The best thing that you can do as a homeowner is to select an ACCA member heating and air conditioning company or contractor to ensure that your comfort specialist has all of the latest and greatest training, tools and professional assistance to best serve you as a customer. In the long term you won't regret it because you will save some money on the utility bill and you will be much more comfortable in your home as a result.