Thank you for visiting Durham Mechanical Services online. This section has been developed to give you information about our services and to provide general information regarding heating and cooling your home.

Selecting a contractor
Choosing a HVAC contractor is much like choosing any other service professional. Quality work should carry a higher priority than a cheap price. There are many individuals, as well as companies, out there that are unlicensed and will work for a very cheap price; but wait until something goes wrong. Suddenly you can't find them anywhere. It's a good idea to select a contractor that relies on YOU the customer for their livelihood. DMS is here for you; taking care of the customer's needs is our highest priority!

Your Comfort…It's Important to Us!
DMS will help you achieve the highest level of satisfaction with your heating and cooling system. We have the expertise to keep your system in top operating condition. Our Preventative Maintenance program enables us to ensure that your system will operate, as it should, when it should. To learn more about our Preventative Maintenance packages, click here.

Why Choose DMS?
When it comes to choosing a Heating and Air Conditioning company, there are hundreds of options in town. When you choose our company, you get personalized service and quality workmanship, all at a fair price.

How Can We Help You?
DMS is the source for your heating and cooling needs. We offer FREE estimates for replacement and new construction equipment. Give us a call at 919-382-6377. Or click here.

Service - We take pride in providing prompt, courteous service. Our service technicians are available after hours for emergency service, if needed, to ensure your comfort. Our service technicians are also trained in the latest technology to ensure your system is well maintained.

Replacements - There is more to buying a heat pump or air conditioners than ratings. The quality of construction and materials used as well as the reliability of the manufacturer and installing contractor can all effect your long-term satisfaction and comfort. The experts at DMS will provide you with the best quality for your heating and cooling system replacement needs at the best price.

New Construction - When building a new home, you get the chance to incorporate all the amenities to afford quality of life. You should put as much thought into your new heating and cooling system. After all, it will be your new home's best friend for several years. Top quality, high efficiency equipment may cost more initially, but it will save you money on utility bills and service calls for years to come. Be sure to weigh all the factors before choosing your new system. DMS can help you make the right decision.


HVAC - Heating, Ventilating and Air Conditioning refers to the indoor comfort industry.

BTU - British Thermal Unit is the amount of heat that will raise or lower one pound of water by one degree Fahrenheit. One the other hand, BTUH is how many BTUs are used per hour.

Ton - Heat pumps and air conditioners are generally sized in tons. Typical sizes for single-family residences are between two and five tons. Each ton equals 12,000 BTUH.

Efficiency - A rating on comfort equipment is similar to the miles per gallon rating on your vehicle. The higher the rating number, the more efficient the system and the lower your fuel consumption will be.

SEER - Seasonal Energy Efficiency Ratio is the amount of cooling your equipment delivers per every dollar spent on electricity. SEER applies to air conditioners and heat pumps. In the past, a unit with a SEER of 6.00 was considered standard efficiency, and a unit with a 10.00 SEER was considered high efficiency. After January 1992, the minimum SEER required by the Department of Energy (DOE) was 10.00 and 15.00+ SEER is considered high efficiency. The DOE currently recommends a unit with a SEER rating of no less than 12.00.


How often should I change the air filter in my system?
Check it at least every month during peak use, and replace it when it looks dirty enough to significantly reduce the airflow through it.

Is Preventative Maintenance really necessary?
Your heating and cooling system is a finely tuned piece of machinery that is designed to squeeze the most from your energy dollars. Your system operates for months on end and if one of the components of that system is not working in harmony with the rest of the system, you are losing money and efficiency. Preventative maintenance inspections often spot small problems before they become large and very expensive problems. Preventative maintenance can also spot dangerous operating conditions that could lead to production of carbon monoxide from the furnace, which is a serious, potentially deadly situation. For a complete list of what is provided with our Preventative Maintenance package, click here.

My heating and cooling system does not keep us comfortable. Should I have a larger system installed?
In most cases, no. Usually the problem is due to poor system design or installation. More likely you need duct work modifications. Contact us a call to assess your current situation. See our service page, or call us at 919-382-6377.

When do I know it is time to replace my system?
When the system starts giving more problems than seem cost effective to fix, especially when major components such as the compressor start malfunctioning or otherwise indicate a need for a service call. When faced with a major repair on your system, we can help you make the right choice for a fair price.

How can I tell if the heat exchanger in my system has cracks?
You can't. Most cracks in the heat exchanger occur in areas that are hidden from view. Even if the cracked areas of the heat exchanger were visible, the cracks themselves are extremely difficult to detect without an experienced eye.

What causes the cracks to form in the heat exchanger?
In the normal course of operation, the heat exchanger experiences repeated heating and cooling, which causes a corresponding expansion and contraction of the metal. Cracks will tend to form in areas of the heat exchanger that are weak, such as the areas that have been welded at the factory. More weak spots and holes will form as a result of corrosion. Corrosion of the heat exchanger often signifies problems with the exhaust venting. What occurs is that water in the exhaust, which contains carbonic acid, cools too quickly and condenses out, draining back down the chimney and onto the heat exchanger where the acid eats away at the metal.


This WebSite is Hosted, Designed and Developed by Jay Schwantes - Durham, North Carolina