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Serving the Greater New Braunfels, TX Area

Serving the Greater New Braunfels, TX Area


How an Old Furnace Can Be Bad News


No matter how much you would like the current furnace in your home to be the only one you’ll ever need, eventually, a time will come when continuing to have it repaired and maintained is throwing money away. There are several warning signs about a furnace that’s over-the-hill, but the easiest metric is its age. (If you don’t know the furnace’s manufacture date, check on the metal plate on the unit.)

The age when a furnace is considered “old” is 15 years, although well-cared-for units sometimes make it to 20 years. We recommend you give serious consideration to replacing a furnace that’s older than 15. Below are the reasons an older furnace can be a problem.

Low original energy efficiency

The technology of furnaces has improved its efficiency over the past 20 years. The older your furnace is, the more likely it comes from a time when efficiency ratings were much lower in general. You’ll find the efficiency rating, AFUE, marked on the furnace. If it’s in the 70%-80% range, it’s far less efficient than the models available now, some of which have an AFUE of 98%.

Energy efficiency that keeps getting worse

No matter what the furnace’s original efficiency rating is, if it’s 15 years or older, it’s going to perform worse. Although regular maintenance helps to keep the furnace close to its original efficiency, nothing will prevent it from dropping when it gets too old. If you are paying more for home heating than you have before, it’s probably due to an old furnace.

Uneven heating

Any central heating system is supposed to provide an even spread of comfort around the house. An older furnace will start to lose heating capacity, and one of the first ways you’ll notice this is discovering cold spots around the house, often in the rooms most distant from the furnace. Scheduling heating repairs in New Braunfels, TX may fix this, but a technician will also tell you when the furnace’s extreme age is causing a heating capacity decline.

Excessive noise

When an unusual noise comes from your furnace, it’s often a signal to call for repairs. When the furnace is just noisy overall, it’s often a signal to call for a new furnace. You shouldn’t have to put up with a heating system that makes banging, clanging, screeching, and groaning noises.

Toxic gas leaks

We don’t want to sound alarmist, but the biggest concern with an older furnace is that it can allow toxic carbon monoxide into your house. The furnace can begin to rust with age because of the effects of combustion gas vapor on its metal, and rust creates the possibility of heat exchanger cracks. A cracked heat exchanger can allow toxic exhaust gases to seep into the air blown into the living spaces. This is the reason you should have CO detectors around the rooms! Please don’t use your furnace if you see rust on it—call us right away to look into the problem and advise on the next steps.

At Thayer Air Conditioning, your comfort is our #1 priority! Call us, we’re already on our way.

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