Previous Tips

Table of Contents

1. Back to Current Tip
2. The AC-Enhancer
3. Is a Heat Pump Right for our Climate?
4. The Most Important Day in the Life of Your Air Conditioner
5. The Truth about the New 13 SEER Law
6. The Truth about the Freon Phase Out
7. Fall Heating Season Reminders
8. What You Need to Know When Buying a New Air Conditioner
9. A/C Changes
10. Winter 2004
11. Filters
12. What Can I Do About High Electric Bills?
13. Why Can't My Air Conditioner Keep Up ?
14. Dust Problems in the Home
15. Pressure Imbalances
16. Happy Holidays
17. Humidity Problems
18. Maintenance Homeowners Can Do
19. Bigger Is NOT Better
20. How Can I Keep My Attic Cooler?
21. Indoor Air Concerns - Air Advice Monitoring
22. Air Quality Concerns
23. Heating Season Checks

    Enhances the Efficiency and Dehumidification Capacity of

Virtually Any Central Air Conditioning System.

 The most inefficient time in the operation of an air conditioning system is the start-up time.  On most systems it takes anywhere from 6 to 10 minutes of run time before the system gets up to its peak efficiency and its peak dehumidification capacity.  The AC-Enhancer^TM allows your existing air conditioning system to reach its peak efficiency in less than two minutes after start-up.  It also causes the system to start dehumidifying almost immediately upon start up.  This makes your existing air conditioning system run more efficiently and dehumidify more than a normal unit.  This saves you cooling dollars and makes your home more comfortable.  And at an installed price of only $249.00 it will pay for itself in a really short time. 

 I have seen a lot of gimmicks come and go in the air conditioning business in the last 30 years, but I have personally tested this unit, and it really does what it says it will do.  It will work on virtually any central air conditioning system.  The system needs to be in good operating condition, but it doesn’t matter if it is new or old.  The other nice thing about this unit is that it can be moved from one system to another.  If you install it on your old system and then when it is time to replace the system  The AC-Enhancer^TM can be reinstalled on your new system and you can continue to enjoy the benefits of its enhancements. 

For More Information Click Here!

Is a Heat Pump Right for our Climate?

If you have an all electric house then you should definitely consider a heat pump when you are replacing your air conditioning equipment.  With the cost of electricity so high these days it only makes sense to heat your house with a heat pump instead of straight electric elements.  The heat pump is between 3 and 4 times as efficient as electric heat.  Many people say that we don’t heat enough in Corpus Christi to even worry about a heater, but we actually have an average of 850 heating hours per year.  The good thing is that 98% of our heating hours are above 32 degrees, and 90% are above 40 degrees.  The heat pump is most efficient above 40 degrees giving us the ideal climate for heat pumps.  On the average you will pay about $800 to $1200 more for a heat pump than for a straight electric heat unit and at $0.16 per kilowatt that will pay for itself in about two years.  If we have another cold winter like we did this year or if the electric rates go up any more it will pay for itself even faster.  Then after that it is extra savings for the life of the unit.

            Some people say that they don’t want a heat pump because they are concerned that if it goes out in the winter they will have no heat.  We always size the electric back up heat to be enough to handle the home by itself.  That way if your heat pump does go down you have the same amount of heat you would have had if you only had electric heat.  This also gives you extra capacity in case we have a really cold winter. 

How the system is installed is critical to the efficiency and longevity of the unit.  Proper installation procedures will ensure that there is no moisture left in the system and that the refrigerant charge is proper.  A unit that is just one pound low on refrigerant can cost you 15-20% on your cooling bill.  If a proper vacuum is not pulled on the system during installation it could cause premature compressor failure.  If a proper refrigerant dryer is not installed in the refrigerant system it could also cause premature compressor failure.  If the blower speed is not set properly it can cause sweating of vents and the unit itself.  If the ductwork is not sealed properly it can cause dust problems in the house, high electric bills, and poor cooling.  It is critical that you choose a company that will install your system properly. 

Ductwork is More Important Than SEER.  What good does it do to install an 18 SEER super high efficiency system on a duct system that leaks and looses 25 to 40% of your efficiency?  I always tell people not to scrimp on their duct system.  This is typically what makes you either happy with your air conditioning system or it makes you hate it.  A good duct system should balance the air to the house so that every room is about the same temperature and the proper amount of air flows to each room.  If you have hot rooms or cold rooms then your duct system is probably not balanced properly.  Also the ductwork needs to be insulated and sealed properly to make sure it delivers the air with the least amount of loss. 

All of these factors are critical in getting the right comfort system for your house and your lifestyle.  Anyone can just change out the "Box" either inside out outside, but getting true comfort in your home requires that we look at the Whole House, ductwork, and equipment and design a system that is right for your application.

Back to Top

THE TRUTH ABOUT THE NEW 13 SEER LAW

            Starting January 23, 2006, the equipment manufacturers will no longer be able to build residential air conditioning systems that are less than 13 SEER efficiency.  Any units still in the manufacturer’s stock or in the contractor’s stock can still be sold.  Once the units that are lower than 13 SEER are depleted from inventory they will be gone for good.  Consumers need to beware of the efficiency games played by manufacturers and some contractors.  The way that the outside unit is matched with the inside unit will determine the SEER rating.  What is generally not told to you is that you can match the system up to get more SEER out of it by sacrificing the moisture removal capacity.  It takes more energy to remove moisture than it does to just drop temperature.  By reducing the moisture removal capacity of the system you can get a higher SEER out of the same unit.  This is partially how the manufacturers are coming up with the higher SEER ratings.  By using a smaller capacity compressor and matching it with a larger outside coil and a larger inside coil you get more BTU’s of total cooling for every Watt of electricity consumed.  This is how they calculate SEER (Seasonal Energy Efficiency Ratio).  But by doing this you also decrease the dehumidification capacity of the system.  This will cause the homeowner to have a tendency to turn the air conditioner colder because they are not comfortable.  Every degree colder you turn your air conditioner can cost you 8-10% on your electric bill.  So if you install a 14 SEER system that does not dehumidify well and you have to run the air at 72 to try and be comfortable you will spend more energy than if you were to run a 13 SEER system that dehumidifies better and allows you to be comfortable at 76 or 77 degrees.

THE TRUTH ABOUT FREON PHASE-OUT

            Regardless of all the hype, Freon 22 has not been proven to cause any problems with the Ozone Level in the upper atmosphere.  The Freon 12 that they used to use in cars was the big culprit.  Freon 22 is however being phased out as a refrigerant.  The phase out schedule is set to stop manufacturing air conditioning equipment that uses Freon 22 in the year 2010.  They will have to stop manufacturing new Freon 22 in the year 2020, and they will have to stop selling the recycled Freon 22 in the year 2030.  The refrigerant that is, as of now, set to replace it is R410a or Puron.  R410a is a blended refrigerant that operates at about double the pressure that Freon 22 operates at.  R410a is also much less forgiving of a refrigerant than Freon 22.  It creates acid much more readily if any moisture is in the system, which can destroy your compressor.  Also since it is a blended refrigerant, if you have a leak that leaks out more than 20% of your total charge you are required to remove all of the remaining refrigerant and replace it with new.  This can be very costly to the consumer especially since the R410a as of now costs about 5 times as much as Freon 22.  Because of these and other disadvantages to R410a we are hoping that before the phase out time for Freon 22 a new, better refrigerant will be developed to take its place.

Back to Top

FALL HEATING SEASON REMINDERS

            Most people think that here in the Coastal Bend we don’t have enough Winter Weather to worry about their heating systems.  Well it is true that our winters are short and usually not very cold, on the average we have about 850 heating hours a year.  That is enough to make it worth while to have your heating system checked by a professional.  The main reason to check your heating system is Safety.  It is very important to check all the safety switches and make sure they are working properly and to check the sequencers on the heating elements to make sure they are working properly.  If the sequencer sticks it could cause the heating element to run all the time and this could cause the unit to overheat.  This also will cause your electric bill to go out of sight.  If you have gas heat you really need to have your system checked every year.  There are many safety switches and sensors to make sure the unit is operating properly and safely and if one of those fails it could cause problems for you that could be dangerous to your family.

Back to Top

What You Need to Know When Buying a New Air Conditioner

Summer 2005

In our Humid Climate there are several factors that are key when buying a new air conditioning system. 

First and foremost is Bigger is NOT Better,  Oversized air conditioners may cool the house down faster, but they short cycle, turning on and off much more frequently.  This does not allow the system to run long enough to pull the moisture out of the air, and also makes the system run very inefficiently.  It takes about 8 to 10 minutes of run time for the air conditioner to reach its maximum efficiency and dehumidifying capacity.  If the unit comes on and runs for only about 5 minutes and then shuts off, it never reaches its full efficiency and just barely starts to dehumidify.  It is the same as driving your car in stop and go traffic versus driving on the highway.  You will get much better gas mileage on the highway.

Second is the Match Up of the inside coil and the outside condensing unit.  The way the system is matched up makes a tremendous difference in the amount of moisture that is pulled out when the unit runs.  If you use the match-up that gives you the highest SEER (Seasonal Energy Efficiency Ratio) rating it will not give you the best dehumidifying.  It is actually better to have a match-up that gets a lower SEER rating, but dehumidifies better.  If your unit does not do a good job of dehumidifying you will not feel comfortable at 76 degrees and you will have a tendency to turn the temperature lower and lower to try and feel comfortable.  This will cost you more on your electric bill than if you had the unit with the lower SEER rating that dehumidified better and you could keep your temperature at 76 degrees or higher.

The Most Important Day in the Life of Your Air Conditioner is the Day it is Installed.    How the system is installed is critical to the efficiency and longevity of the unit.  Proper installation procedures will ensure that there is no moisture left in the system and that the refrigerant charge is proper.  A unit that is just one pound low on refrigerant can cost you 15-20% on your cooling bill.  If a proper vacuum is not pulled on the system during installation it could cause premature compressor failure.  If a proper refrigerant dryer is not installed in the refrigerant system it could also cause premature compressor failure.  If the blower speed is not set properly it can cause sweating of vents and the unit itself.  If the ductwork is not sealed properly it can cause dust problems in the house, high electric bills, and poor cooling.  It is critical that you choose a company that will install your system properly. 

Ductwork is More Important Than SEER.  What good does it do to install an 18 SEER super high efficiency system on a duct system that leaks and looses 25 to 40% of your efficiency?  I always tell people not to scrimp on their duct system.  This is typically what makes you either happy with your air conditioning system or it makes you hate it.  A good duct system should balance the air to the house so that every room is about the same temperature and the proper amount of air flows to each room.  If you have hot rooms or cold rooms then your duct system is probably not balanced properly.  Also the ductwork needs to be insulated and sealed properly to make sure it delivers the air with the least amount of loss. 

All of these factors are critical in getting the right comfort system for your house and your lifestyle.  Anyone can just change out the "Box" either inside out outside, but getting true comfort in your home requires that we look at the Whole House, ductwork, and equipment and design a system that is right for your application.

Back to Top

February 2005

A/C Changes and Government Regulations

The federal government has gotten into the Air Conditioning industry again and it could mean trouble for people in South Texas.  The government has decided that as of January, 2006, Air Conditioning manufacturers will not be able to build any air conditioning equipment that is less than 13 SEER.  While that may seem to be a good thing on the surface, it may cause greater problems for all of us that live in humid climates. 

            You would think that with our heat and the 2600+ cooling hours per year, it would pay to go to the most efficient air conditioner you could buy.  The problem is that with our high humidity about 350 days of the year, we need a unit that will dehumidify the most that it can.  The A/C manufacturers figured out a while back that they can increase the SEER rating of a system by making the inside and outside coils bigger, and making the compressor smaller.  This will give more total BTU’s of cooling for less electricity.  The problem with this is that in doing this they greatly decrease the latent capacity of the system.  This is the capacity of the system to remove moisture.  The unit will run and lower the temperature in the home, but will not remove as much moisture as the older systems would.  With a higher relative humidity, the homeowner does not feel as comfortable at their normal temperature setting.  This in many cases causes the homeowner to turn the thermostat colder to try and be comfortable.  Every degree that you turn your thermostat below 78 degrees in the summer adds about 12% to your cooling expense.  If you have to set your thermostat at 72 degrees to be comfortable because the new Super High Efficiency air conditioner does not remove enough moisture, then you are not going to save any energy, and in many cases it cost you more. 

            The match up of your inside equipment with your outside makes a world of difference in the amount of moisture your system removes, and the comfort you feel inside.  Squeezing the most SEER out of a unit does not help you in the long run.

            Another problem comes into play when you keep your home below 72 degrees in the summer time.  With our high dew point temperatures here, on many days this can cause the inside of the walls in the home to start sweating.  If the dew point temperature  is 76 degrees, then any surface cooler than 76 will start to condense water, just like a cold soda can in the summer time.  This moisture condensing inside the walls of the home will cause mold growth. 

            The key is to make sure your air conditioning system is sized properly, Bigger is Not Better, and to make sure the inside match with the outside unit is designed for maximum moisture removal.  This will save you money in the long run and may even save your home.

Back to Top

Winter 2004
Happy Holidays

Back to Top

Back to Top

July 2004
Indoor Air Concerns

Back to Top

June 2004
How Can I Keep My Attic Cooler?

 During the hot summer months we all start thinking of ways to reduce out electric bills.  One of the biggest heat sources in our home is the attic.  The attic load is much more than the walls and windows.  I see people spending lots of money on new energy efficient windows and not investing in more attic insulation.  In our area we recommend R30 for the insulation in the attic.  This will help reduce the amount of heat that comes down from the hot attic.  If you go up in your attic (your favorite place in the summer I am sure) and you can see the ceiling rafters above the insulation then you need more. 

But insulation only keeps the attic heat from transferring into our homes, it will also help if we can get the attic cooler.  An attic in the afternoon in the summer can be 120 to 140 degrees and some even hotter.  Many people think that the way is to add powered attic fans to draw more air through the attic.  In most cases this causes more problems than it helps.  These powerful exhaust fans actually pull the conditioned air out of the house and into the attic.  Yes this cools the attic down, but it actually costs more because you are loosing your conditioned air from the house to the attic.  The air you loose to the attic is then drawn into the house from outside which causes your cooling bill to go up. 

The “whirly-bird” vents that you see on many homes that spin with the wind to draw air out of the attic are not really made for our area.  Once the wind gets over about 8 miles per hour the spinning actually hinders the airflow and decreases the amount of hot attic air that can escape.  We very seldom have days that have lower than 8 mph winds.  The other problem with these is the bearings go bad and they get very noisy. 

The best ventilation is the continuous ridge vent.  This is a vent that runs along the entire ridge of the roof.  It is at the highest point in the attic so the hot air rises to go out it.  You must make sure you have sufficient soffit vents to allow for free airflow.  The problem with this is that unless you install it when you are installing a new roof or building your home it is not very practical to retrofit an existing house.

The standard “turtle-back” vents on the roof are the most common and are very effective when enough are installed.  They can be added to an existing roof and allow for a lot of airflow when installed properly.  They also require that there be enough soffit vents to allow for free airflow.

Another thing to check for is to make sure your vents are not restricted.  I have seen many times where the soffit vents are completely plugged up either with insulation that was blown in the attic, or from dirt and rust from the airflow from outside.  You need to check yours to make sure they are open and will allow the maximum amount of air to pass through them.

Actually the winter time is the best time to do anything in the attic, that is when it is cooler and almost bearable to be up there.  The problem is that we have a tendency to not think about these things until we need them.  A little thinking ahead can make the job a lot more bearable.

Back to Top

May 2004

Bigger Is NOT Better

 At this time of the year many people are starting to think about replacing their air conditioners to get ready for the hot summer months.  One common misconception is that “Bigger is Better”.  When it comes to air conditioning that is definitely not the case.  Bigger is actually much worse in many ways.  A lot of people think that a bigger unit will run less and cost them less on their electric bill.  It is true that it will run less, but that does not cost less.  The bigger unit will start and stop more, which is very inefficient.  It takes approximately 8 to 10 minutes of run time for an air conditioner to get up to its full efficiency.  If the system starts and stops it is like driving your car in stop and go traffic, versus driving on the highway, you get much worse mileage in stop and go traffic.  Just the same your air conditioner is much less efficient with more cycling. 

The other disadvantage of the starting and stopping is that the unit does not really start dehumidifying until it has been running for about 8 to 10 minutes.  You get much worse dehumidification from an oversized unit and then you have a tendency to turn the thermostat much colder to try and get comfortable.  Every degree colder you turn your thermostat costs you 10 to 15% more energy, which makes the larger unit cost you much more to run.

It is critical to get the sizing correct when you are replacing your air conditioner, it is something that you typically only do once every 10 to 15 years, and you don’t want to be stuck with the wrong size for that long.  A simple rules of thumb is if during the hottest part of the summer and the heat of the day, your unit cycles off, then you have some excess capacity.  A properly sized unit should run 100% of the time when it is 96 degrees outside and 76 degrees inside.  Once it starts cooling down outside then it will start to cycle off some. 

Sizing a unit for a home properly takes many factors into consideration such as, square footage, ceiling heights, windows, doors, attic and wall insulation, infiltration or leakiness, solar loads, appliances, and people loads.  There is no square foot per ton method that is accurate because of all the other factors that can vary so much. 

Back to Top

April 2004

Maintenance Homeowners Can Do

With the South Texas heat fast approaching you may be wondering what you can do to keep your air conditioner cooler and your electric bill down.  Here are some tips to help you survive the summer heat. 

1. Keep your filter clean and changed regularly.  A dirty filter can make your unit run harder and decrease your capacity and efficiency.  Cleaning and Maintaining Air Conditioning Filters
2. Make sure your drain line is kept clean and flowing properly.  You may want to pour some diluted Clorox water ( ¼ cup Clorox to ¾ cup water) through the drain.  Make sure you turn the unit off first and do not pour it in the drain pan.  After your pour it down the drain wait about 5 minutes and then pour some fresh water down it to flush the Clorox fumes out of the line.  The chlorine fumes can be very corrosive to any metal.  Keeping Air Conditioning Drain Clean and Flowing
3. Keep your outside unit clean and free of debris and plants.  Grass clippings and vines can clog the outside coil and restrict the airflow.  This will decrease your capacity and efficiency.  Make sure that bushes and shrubs do not grow too close to the unit and restrict the airflow.  The air must be able to escape freely from the discharge of the unit.  Any restriction in this area can cause the hot air to be recirculated back through the unit.  This will make the unit work much harder and reduce the efficiency and capacity.  Cleaning Your Air Conditioner
4. Rinse the coil on the outside unit.  This will clean the loose dirt, salt, and sand from the coil.  Do not wash it with pressure, simply rinse it from the top down to let the dirt freely flow out.  Washing it with pressure may pack the dirt into the center of the coil.  Pressure should only be used from the inside out to push the dirt out the way it came in.  Rinsing the coil should be done about once a month during the cooling season.
5. Keep your thermostat at the highest temperature setting that you are comfortable at.  Raising the temperature 1 or 2 degrees can save you as much as 15% on your cooling bill.

Probably the most important thing you can do to make sure you are ready for the summer heat is to have your cooling system fine-tuned by one of our skilled service technicians.  A unit that is just 1 pound low on refrigerant can cost you 15 to 20% on your cooling bill.  Ask us about a Peak Energy Savings Agreement that can save you money year round.

Back to Top

March 2004

Humidity Problems

Humidity in our homes is a major concern in our climate.  If you have to turn your thermostat below 74 degrees in the cooling mode to feel comfortable, then you have a humidity control problem.  The new High Efficiency air conditioning units may be partly to blame.  The government has mandated that the manufacturers make their equipment more energy efficient, and the consumers have used the SEER rating to compare units.  And for the most part that is the only comparison that most homeowners know how to make when it comes to their cooling equipment.  What most companies wont tell you is the tricks they play to get the SEER number up higher.  

1. Match a 12 SEER condensing unit with a larger inside coil to get it up to 13 or 14 SEER.  This cuts the dehumidifying capacity of the equipment way down.
2. The Manufacturers use a smaller compressor with a larger outside coil and inside coil to get more efficiency out of the units.
3. It takes more energy to pull moisture out of the air then it does to cool the air, so if you pull less moisture out you can cool the air using less energy.  That raises the SEER number to make the unit look more efficient.  The problem is you have to turn your thermostat much cooler to feel comfortable and you end up using more energy.
4. Oversizing the equipment to minimize the run time.  This hurts on the efficiency and the dehumidification of the equipment.
5. Variable Speed blowers set to ramp up to speed slowly.  This increases the dehumidification of the equipment some, but in many cases causes the inside unit, the ductwork, and the supply grilles to sweat.
6. Smart Thermostats that override temperature settings to get more dehumidification.  This can cause overcooling of the space and can actually bring the entire house down below the dew point temperature.  This can cause sweating inside the walls and cause water and mold problems.

Some contractors even install electric reheat connected to a humidistat to control humidity.  This will do the job of controlling humidity, but it is running your air conditioner and heater at the same time.  If you can afford your electric bill this will work in many cases.

 An air conditioning system alone cannot control humidity in your home 365 days a year.  When it is cool outside and raining, neither the air conditioner nor heater is running, so what is going to control the moisture in your home?  The only thing that can do this is a Whole House Dehumidifier.  We recommend the Thermastore units because they do the best job and are the most effective year round.  In most cases we have found that our customers that have installed these Whole House Dehumidifiers tend to turn their thermostats up 6 to 8 degrees warmer and feel much more comfortable.  The energy savings of turning the thermostat up in most cases more than pays for the energy used by the dehumidifiers.

 If you feel that you may be having a problem with humidity control, call us for a no obligation check of your home.  We have the equipment to test and monitor you humidity level and help find the places where the moisture is coming into the home. 

Back to Top

December 2003

Happy Holidays

 I would like to take this opportunity to thank all of my friends and customers for a great year.  2003 has been a year of changes for me, and most all of them have been for the better.  I have been truly blessed with so many friends, co-workers, and customers that have supported and helped me through the year. For that I am truly thankful. 

 I also want to thank all of my old and new customers that have given me the opportunity to earn their business and their trust.  I am thankful and proud to know that so many people that I have had the privilege to do business with in the past have valued that relationship as much as I have and followed me to my new company.  

I am also very thankful that I have a wonderful and understanding wife that has stood by me and supported me in making some of the toughest decisions in my life.  I thank God every day for her and for my family.

I would like to personally wish everyone Happy Holidays and a Happy New Year.  And I wish you all the best for the upcoming year.   

Sincerely,

 David Mathews

Back to Top

November, 2003

Pressure Imbalances in Homes

 Most people don’t realize the potential problems that can be caused by pressure imbalances in their homes.  A pressure imbalance is when the pressure in one part of the home is different from the pressure in the other part.  It can be either higher or lower.  Pressure Imbalances can cause dust problems, humidity problems, and cooling or heating problems.  They are an additional cause for infiltration of outside air, which can bring in heat, dust, and humidity.

 One of the most common causes of a pressure imbalance in a home is when one or more of the rooms are closed off.  When you close the door to a bedroom or other room in the house and do not allow the air to flow freely back to the return air grille you cause a pressure imbalance in the home.  As the air conditioner or heater runs and blows air through the ducts it will build up a higher pressure in the room with the door shut.  In the main part of the house where the return air grille is it is trying to draw air in to the return and will create a negative pressure on that part of the house.

 When this happens any openings to the outside in the room with higher pressure will allow air to flow out.  Every CFM (Cubic Feet per Minute, the measure of airflow) of air that flows out in this room has to be made up by a CFM of air flowing in the main part of the house.  Most of the time the air that flows in comes from the attic which is hot, humid, dusty air.  So closing a bedroom door that does not have a return air in it does more harm than good.

 Another cause of pressure imbalances is when there are leaks in your central air duct system.  If you have supply side air leaks this will cause a negative pressure in the home and will create a suction to draw air in from any opening to the outside or attic.  This brings in hot, humid, dusty, unconditioned air into your home.  If you have return air leaks, this will cause a positive pressure on the house and will blow conditioned air out the openings to the outside.  This also puts an extra strain on the air conditioning system because it is drawing in hot, humid, dusty air from outside and trying to condition it.

 The key is to not close the doors to any rooms that have an air conditioning vent going into them.  You also need to make sure that your duct system is not leaky.  Your home comfort and energy bills will be greatly improved if you take some precautions in these areas.

Back to Top

October 2003

Dust Problems in the Home

  Dust problems in the home can be, needless to say, quite aggravating.  There are many possible causes for indoor dust problems and this month we will discuss a few of the more common ones.  There are also some common myths about dust problems. 

 One of the most common myths about dust in homes is that the duct system is blowing dust into the house.  It is very uncommon for the dust to be blown into the house by the duct system.  The ducts cannot generate dust and even if you are using a poor quality filter on your system, the dust will be caught on the evaporator coil before it passes through to the duct system.  Some very small particles may pass through, but these are the microscopic particles that you cannot see with the naked eye anyway.

 The duct system can play an important role in the amount of dust in the house even though it does not create the dust.  Most severe dust problems are caused by severe duct problems.  If the duct system leaks air to the attic it can create a pressure imbalance in the home, which can cause the house to fall under a negative pressure.  This negative pressure causes the house to draw air in from outside through any crack or crevice that it can.  Most commonly these leaks are to the attic, which draws in very hot, humid, dusty air.  This can increase the load on your air conditioning equipment and create dust problems.

 Another way that the duct system can cause an increase in the dust in your house is at the supply grilles.  If the connection where the duct passes through the sheetrock is not sealed and there is a crack between the sheetrock and the supply “boot” then when the air conditioner is blowing air through the grille it creates a siphoning effect on this crack.  This draws hot, humid, dusty air from the attic into the house.  This is usually the cause for the grilles to get dirty, and the streaking commonly seen around supply grilles.  This can also be a cause of Mold forming on the grilles.  The hot, humid air hitting the cold supply grille causes condensation and with the dust and dirt it give mold a perfect breeding ground.

 Ceiling fans can also be a big dust problem.  In most cases the electrical box that the ceiling fan connects to is very leaky to the attic space.  When you turn the ceiling fan on it is actually drawing hot, humid, dusty air in from the attic and spreading it through the room.  The fans with the large beauty ring on the ceiling are usually the worst because that ring is there to cover the big hole above.  If your fan blades get covered with dust rapidly it usually means that the fan is drawing in a lot of dust.  The opening above the fan needs to be sealed to stop this.

 One cause of major dust problems in a house is when the attic has Cellulose insulation blown into it.  The Borax powder that is mixed with the cellulose insulation to make it more fire retardant and make it blow in easier is horrible for dust.  This material seeks out any small crack or crevice to come into the house.  The worst dust problems that I have seen have been attributed to recently blown in Cellulose insulation.  The dust actually balls up when collected like a fibrous material and looks white.  There is actually very little that can be done to cure this problem, but you can make sure that the house is as tight as possible and the ductwork is as tight as possible so there is no driving force to push it in.

 There are other causes of dust in homes.  Just living crates dust day to day.  Anyone who sells you a high efficiency filter and tells you that it will eliminate dust in your house does not know what he is talking about.  A filter is there to keep the equipment clean.  The dust that you can see is heavy dust and generally does not stay airborne long enough to get drawn to the return and go through the filter.  It settles out too quickly.  If you have any specific questions please e-mail them to me at david@ccac-ac.com.  Next month I will be talking about pressure imbalances in the home and what closing a bedroom door will do to your system.

Back to Top

September 2003

Filters

This month we will talk about Filters.  This is a common question among people that I talk with.  What kind of filter should I use, and how often should I change it.  First we will talk about what kind of filters. 

 There are many different kinds of filters out there on the market.  The most common filter is the 1” throwaway filter.  Of these there are two main types.  The Fiberglass filter, which is normally, a blue color and the fibers in the filter are actually made of fiberglass.  This is the type of filter normally sold in the grocery and discount stores.  This is a very inefficient filter.  If you hold this filter up and look through it you could actually read the paper through it.  If you can see through it easily then it is not going to stop the fine particles of dirt from passing through it.  A very visual test of a filter is to hold the filter out and sprinkle salt on it.  If the salt passes right through the filter then it is not going to filter any of the small particles out of the air.  The other common type of 1” throwaway filter is the polyester fiber filter.  This filter is the better of the two and is typically a denser filter than the fiberglass.  It is still not considered a high efficiency filter, but is much better than the fiberglass.

 The 1” pleated filter uses a denser polyester media and a lot more surface area.  The material is compressed into pleats to get all the surface area into the size of filter to fit your unit.  The problem with the pleated filters is that they may be too restrictive for the filter size and the unit.  Make sure that you have a large enough filter size for the tonnage unit you have before converting to the pleated filter.

 There are also 2” and 4” pleated filters that use the same media as the 1”, but because of their extra thickness they have more surface area and need to be changed less often.  The efficiency of these filters is the same as the 1” pleated.  In most cases your unit has to be fitted with a special track or bracket to allow you to use these thicker filters.

 The next step up in filtration is the Hepa-Type filters.  The April-Aire or Space-Guard is the most common of these filters.  This is an excellent filter for a residential air conditioning system.  This filters out particles as small as 1 micron in size and when installed properly in the system it will keep the coil and blower and the entire air conditioning system clean for the life of the unit.  We have removed units that have had a Space-Guard on them for 14 years and the coil and blower are still clean.  One other advantage of this type of filter is that normally you only have to change the filter out every six months to a year. 

 The UV filter would be the ultimate in filtration.  This filter such as the Lennox Pure-Aire, not only cleans the particles out of the air, but the UV kills and molecularly decomposes the organic compounds passing through it.  It also does an excellent job of removing odors and volatile organic compounds from the air.

 Any filter that you use can only remove the particles in the air that are bigger than the holes in the filter.  And they will only clean the air that passes over them.  It is critical to make sure that there are no air leaks between the filter and the unit.  Any leak can allow unfiltered air to be drawn through the system.  If anyone tells you that a high efficiency air filter will make it so that you do not have to dust anymore, they are lying and don’t know what they are talking about.  Most dust particles that settle on your furniture are very big and fall out of the air fairly fast.  The filter will only catch the particles that are airborne and pass through the system.  Next month we will talk about common causes of dust in homes and what can be done about it.

 The final thing on filters is How Often Do I Change My Filter.  It actually does no good to change a clean filter.  Filters by the way they work are actually more efficient when they have some dirt on them.  As the filter starts to Load Up it starts filling in the hole size in the media.  The smaller hole will then catch more of the dirt particles than the clean, bigger hole.  The key is to not let the filter get so dirty that it starts to restrict the airflow.  I would rather see a customer change the filter too often than not often enough.  A lot of people set up their filter changing on a routine and do it weather it needs it or not.  If your filter needs to be changed monthly, then change it when you write out your house payment or rent check each month to remember.  If it is quarterly then set it up for the last day of March, June, September, and December.  If it is on an annual basis, then set it up on a birthday, anniversary, or holiday.  The main thing is to change it before it gets too dirty and starts causing problems with your cooling system.

Back to Top

August 2003

What Can I Do to Keep My Electric Bill Down?

Just about everyone that I have talked with has gotten the highest bill they ever had this month.  There are several things that a homeowner can do to keep their unit working as efficiently as it can.  Keep the filter changed on a regular basis is one good idea.  It does no good to change a clean filter, but don't let it get too dirty either.  A restricted filter makes the unit work a lot harder to push the air through it and hurts the efficiency.  You also need to use the right type of filter.  You don't want a filter that is too restrictive such as an electrostatic filter.  Next month we will talk about filters and the different options there.

Make sure the outside air conditioning unit (condensing unit) can breathe freely.  If it is restricted with bushes, fences, awnings, or covers, it can effect the cooling of the unit.  I have seen people build covers for their units to shade them, when in fact what they did is restrict the airflow and cause recirculation of the hot air being blown out of the unit.  This makes the unit think it is hotter outside than it is and makes it work a lot harder to cool the house.  It is a good idea to rinse the outside coils down with a garden hose a couple of times each summer.  Make sure the unit is turned off.  Then rinse water down the coil to rinse off the dirt and salt.  Do not spray into the coil, this will lodge the dirt in deeper.  If the coil is packed with dirt it will require a professional to disassemble the unit and wash the dirt out from the inside out.  

Look at the condition of the outside coils.  If they are showing signs of corrosion, or if you can see the tubing where the fins have corroded off, it may be time to start thinking about replacing the unit.

You can also do the feel test.  The smaller copper line coming out of the outside unit should be about 10 to 15 degrees warmer than the outside temperature when the unit is running.  If you grab the line and it is hotter than that, or is so hot that you cannot comfortable hold it, then there is a problem with the outside unit.  Usually it is either a corroded or a dirty coil outside that causes this.

Another big factor in the high utility bills is the ductwork.  The ducts need to be sealed and insulated in the attic.  If there are any air leaks or broken ducts this will cause the electric bill to go out of site.  If you have a unit in a closet and you look under the platform and see the 2x4 studs then you may have leakage from the attic into the return.  Drawing this hot attic air into the return greatly reduces the efficiency and capacity of the cooling system.  We will discuss this in more detail in the coming months.

The best thing to do about high electric bills is to contact us for a service check up.  Our trained technicians can diagnose your problems and if there are infiltration or duct leakage problems we can find the solution to get you cooling efficiently.

Back to Top

July 2003

Why Can't My Air Conditioner Keep Up?

With this extreme heat that we have been having most air conditioners in Corpus Christi are working at their limits.  The standard design temperatures for Corpus Christi, are 95 degrees outside with 75 degrees inside.  The problem is that the design conditions do not always take into consideration the excessive humidity levels.  Currently we are experiencing high humidity levels and warm low temperatures, so your air conditioner does not have time to catch up even at night.  It is very common for the unit to run all day long with these conditions.  If you are trying to keep your home cooler than 75 degrees inside it will struggle and even a properly sized unit may not be able to keep up.  

If your air conditioner is low on refrigerant it will decrease the capacity of the system and during the hottest part of the year it will not be able to keep up.  The answer is usually not a bigger air conditioner, this can increase humidity control problems.  The best money spent in our climate is to have a licensed professional check your air conditioning system every year.  In most cases they can save you more money on your electric bill each summer than what it costs you to have the service.  Plus you will have the peace of mind in knowing that your system is running at its peak efficiency.

There are many other potential problems with a house that can cause the air conditioner to not be able to keep up.  I have seen many houses where the return air of the unit is open to the attic space.  This causes the unit to draw air that may be 120 degrees or hotter in and try and cool it.  This kills the capacity and efficiency of your unit.  

These can all be checked by one of our skilled technicians.  Call us today at 361-855-3088 or E-mail me any questions at david@ccac-ac.com

Back to Top