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Serving the Greater New Braunfels, TX Area

Serving the Greater New Braunfels, TX Area


Signs of an Old Furnace: Is It Time for a Replacement?


As spring arrives, you’ll be letting your furnace have a lovely break from all its hard work. But before you forget about it entirely, how was it doing this past winter? Are you certain it’ll be up for another year of keeping your home cozy, or do you have some doubts? This would be a good time to consider your options, so you’ll have plenty of time to select a furnace replacement if you need to. If you’re not sure, here are some signs that it’s time to replace your furnace.


The life expectancy of a furnace depends on its fuel source. While a gas furnace should last about fifteen years, an electric one can keep chugging along for twenty years or possibly more. If you’ve already exceeded that projected lifespan, you should be aware that your furnace could fail at any point. You might rather replace it during the summer than have to scramble to get a new one installed in January.


The ages we mentioned are for furnaces that have received professional maintenance annually. If you haven’t been diligent about having your furnace maintained, that life expectancy will be much shorter. Complete lack of maintenance can cut a furnace’s life in half, because dust and grime, lack of lubrication, and tiny issues going unaddressed put a lot of strain on the system.


Wear and tear are unavoidable, even with maintenance. At some point, generally in the last year or two that a furnace is able to function, the efficiency will drop, and nothing can be done to bring it back up again. If you were shocked by this past winter’s heating bills, it may be because your old furnace in San Marcos, TX is nearing the end of its life. It’s also possible that your furnace was never particularly efficient, and you’re interested in upgrading to a new model to improve your energy efficiency and lower your utility bills. There are some great options available now!

Repair Needs

There are two ways to look at furnace repairs. The first is the cost of a repair. If a single repair will be more expensive than half the cost of replacement, it is probably a poor investment, especially if the furnace is already ten or more years old. The second is frequency. Toward the end of a furnace’s life, it will need more frequent repairs. Multiple repairs during a single winter is a bad sign, and if you don’t choose to replace it, it is likely that you’ll only be dealing with an even higher number of repairs next winter.


This is the death knell for furnaces. Give your furnace a quick visual inspection. Do you see any rust, bubbling, or flaking anywhere on it? It typically takes many years for this to occur, and is unlikely to happen to a new furnace. But when it does happen, it can be dangerous. If that corrosion is affecting your heat exchanger, for example, it may be allowing combustion gasses out into the air you breathe, posing a potentially-deadly carbon monoxide hazard.

If you’re still not sure whether your furnace needs to be replaced, we’d be happy to help you evaluate it and discuss your repair or replacement options.

At Thayer Air Conditioning, your comfort is our #1 priority! Contact us today.

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