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How often should I replace my filter?

It depends on a number of factors. How often you clean, if you have pets, or how often you open the windows can all affect how quickly your filter gets dirty. On average if you have a 1" filter you should check or replace it once a month. If you have a 4" filter you should check or replace it once every three to six months.

How long does an HVAC system last?

On average a system may last anywhere between 10 to 15 years depending on the scheduled maintenance, and quality of the installation. If your system is over 10 years old you should start entertaining the idea of looking for a new system.

As HVAC systems age their operating efficiency decreases. The result is higher operating costs, and less comfort. Also older systems will require more repair and maintenance to operate. A newer system will be quieter, more efficient and need fewer repairs.

My outdoor unit isn't working. If I replace it will be more efficient?

Maybe, but efficient operation is determined by all of the pieces of your system - not just one. The outdoor unit, indoor unit, and furnace (if applicable) all work together to lower your operating costs. See this website for more information on unit combinations: http://www.ari.org/homeowners.aspx

The efficiency could actually be lower than before simply because the newer unit is not designed to work efficiently with older equipment. Attaching a new outdoor unit with older indoor equipment could also reduce the life of the system as a whole for the same reason.

Another important issue is the type of refrigerant. R-22 was the go to refrigerant for most residential and light commercial applications in the past. However, due to EPA guidelines this refrigerant is being phased out for a newer refrigerant: R-410a. The new refrigerant will not work with older equipment.

If your system uses the older refrigerant you have two options. The first is to replace the old unit with an R-22 unit. We do not recommend this for several reasons:

  1. The warranties on these units are much shorter.
  2. The old refrigerant may not be available in the future, and will be very expensive.
  3. Not cost effective. You will eventually have to replace the entire system.

Or you can replace the whole system. The new system will:

  1. Have exceptional warranties.
  2. Be more energy efficient.
  3. Likely be quieter.
  4. The refrigerant will be available in the future.

What if I install a bigger system?

See our article on The Truth about Short Run Cycles.

Should I purchase a Maintenance Contract?

Yes! A Maintenance Contract ensures that your system will operate at peak efficiency and can prevent problems before they happen.
See our Maintenance Contract page for more information, and for the benefits of the maintenance contract.

I have allergies or asthma, is there anything you have that can help me?

Yes!  We have many products that can help you. Take a look at these websites first to get some tips on what you can do now, and how to proceed:


To help control some of the factors that trigger allergies and asthma its best to take a three step approach:

  1. Ventilation and Fresh Air. Proper ventilation and fresh air can help in a number of ways. A normal house will "breathe" without ventilation and fresh air. This causes air to leak from crawlspaces, under the house, the attic and wall cavities into the living space. As you can imagine this air is not really "clean" and it is not conditioned. So it not only makes the air "dirty" it also contributes to how energy efficient your house is. In the HVAC industry we call this effect infiltration. There are a number of things you can do to help control infiltration, check out the Energy Efficiency Tips page for more information. Those tips can help a lot, but no matter how much you seal your home air will always find a way in due to changes in air pressure from day to day. The best thing you can do is have a ventilation and fresh air system installed to control the movement of air in and out of your home.
  2. Humidity Control. Controlling humidity is extremely important for indoor air quality. Bacteria, viruses, and mold all thrive in varying levels of humidity. Take a look at the chart below to see how humidity effects growth of these organisms.
    humidity chart475
    As you can see maintaining a humidity level somewhere between 40%-55% is crucial. In North Central Texas we usually don't have a problem with too little humidity. Our problem is too much humidity. A properly sized air conditioning system should control humidity levels to an acceptable level. If not a dehumidifier can be installed to help better control the humidity in your home. See these articles for more information: The Benefits of Good Ventilation, Mold and Mildew
  3. Filtration. Replacing your filter on a regular basis is good, but upgrading your filter system to a High Efficiency filter is better. High MERV (Minimum efficiency reporting value) filters have the ability to catch more than just dust. They also have the ability to catch and store smaller particles like bacteria, mold, dust mite debris, animal dander, and much more. The Bryant Perfect Air Purifier is an excellent addition to any system. Take a look at the brochure for more information especially if you have allergies.

If you are interested in any of these options please give us a call. We will be happy to help you.

What about mold?

Mold grows in moist environments. There two ways we can help you control mold growth. The first is to ventilate all areas of the house that generate humidity such as the laundry room, bathroom, and kitchen. Second, install a UV Light near your indoor unit. During the summertime the inside of your indoor unit is cold, moist, and dark, perfect conditions for mold growth. Installing a UV Light in your indoor unit is the best way to prevent it.

I'm worried about Carbon Monoxide in my home, what can I do?

There are two things you can do. The first is to purchase a carbon monoxide detector, if you have an old one, replace it. Second, have an experienced HVAC company service your heater at least once a year.

If your Carbon Monoxide detector goes off get out of the home immediately. If you and another person in the house wake up with a headache and/or having difficulty waking up seek medical attention immediately. Then call your HVAC contractor to assess the problem.

Here is some further information:


How can I reduce my energy costs?

See our Energy Efficiency Tips page.

What do SEER, HSPF, AFUE and EER mean?

Let's break apart the acronyms first:
SEER- Seasonal Energy Efficiency Ratio, EER- Energy Efficiency Ratio. These two are related. They measure the energy efficiency of air conditioning units. The higher the number the better the efficiency. The minimum SEER that is available is 13 SEER.

HSPF – Heating Seasonal Performance Factor. This measures the energy efficiency of Heat Pumps only. Same as above, the higher the number the more efficient it is. The minimum HSPF is 7.7.
Putting dollar amounts to SEER ratings is difficult to do accurately because there are so many factors that are different with each household and each type of equipment. The basic idea is this: if you have a 10 SEER unit, and your options for a replacement are a 13 SEER and a 17 SEER the 17 SEER system will save you more money than the 13 SEER system.

AFUE – Annual Fuel Utilization Efficiency. Everything that burns has an AFUE from wood stoves, to ultra-efficient gas heaters. The minimum AFUE for natural gas furnaces is 80%. The higher the percentage the more efficient it is. In other words on a 60% AFUE furnace, for every $1.00 spent on gas, 60 cents heats the house and 40 cents goes up the flue vent. The highest efficiency natural gas furnace available is 96%. If you have propane ask us how a 90%+ furnace can help save you money.

What is a Heat Pump?

To understand what a heat pump does we need to discuss the refrigeration cycle very briefly.

Refrigeration is the practice of taking heat from one place and moving it to another. Your air conditioning system during the summertime uses this process to take heat from your home and move it outside, thus making your home cooler and more comfortable.

A Heat Pump can not only do that, but it can also take heat from outside and move in inside, even if it is cold outside! Why do this? Because this process is much more efficient than using an electric heat source to heat your home, and if you don't have natural gas source available this might be the most cost effective option to you.

Some of my rooms are really hot/cold but the rest of the house is fine, what's the problem?

There could be a number of issues ranging from a problem with the duct system, uneven distribution of insulation in the walls or attic, or even an undersized air conditioner or heater. In some cases increasing airflow, or air balancing will solve the problem. In other situations the system may be too undersized to properly take care of the house as a whole. Each situation is different. Give us a call to set up an appointment to see what we can do to help you.

What temperature should I set my thermostat?

Speaking from an energy efficiency standpoint for our area in and around Dallas, Texas: 68 degrees in the winter, and 78 in the summertime. Never set your thermostat too low in the summertime -  it could cause your air conditioner to freeze.

I'm looking for a builder, which do you suggest?

See our New Construction page.


Call Wolverton Air
at 1-800-905-2665

Wolverton Air Conditioning and Heating North Texas


24 Hour Emergency Service

Commercial · Sales · Service · Residential

Dallas County


License# TACLA000133C, TACLA39122C

Ellis County


License# TACLA000132E








Wolverton Air is the oldest family-owned HVAC company in Dallas County - Since 1939