The most obvious sign you need furnace repairs is when it stops working—but no one should wait that long before taking action. Winter, the season with the heaviest furnace use, is no time for dealing with broken-down heating equipment. That’s why it’s so important to learn the less obvious signs your HVAC system needs professional attention.

They’re not necessarily even difficult to notice; you just need to know how to recognize them:

• Banging & Thumping Noises: Furnaces are often noisy, so this might not seem worrisome. However, unusual noises do merit inspection. Thumping and banging sounds, especially, may indicate loose or worn parts, and the situation will only deteriorate if you ignore it.

• High Winter Utility Bills: Your bills will obviously be a little higher during the winter, since you’re using your furnace more often. However, it’s worth comparing your current winter bills with past ones. If you’re paying a significantly higher amount than before, it may be due to efficiency problems, which should be solved with furnace repairs or better home insulation.

• Lifespan: Most furnaces can be expected to last about 12 to 15 years. If yours is around that age or older, it would be prudent to replace it preemptively. At that point, it may already be requiring frequent repairs. It could even break down soon.

• Over-Cycling: When properly sized for your building, your furnace will cycle on and off to maintain your desired temperature. But if it does this constantly, you have a problem. Furnaces that cycle too much will waste electricity without making your home warmer. If yours over-cycles, first check it’s not due to a clogged air filter. If that’s not the issue, you may need a professional to troubleshoot it.

• Flu-Like Symptoms: if members of your household have been experiencing symptoms like nausea, headaches, or respiratory issues, it may indicate problems with your furnace or ductwork—and potentially even carbon monoxide leaks. If the latter is the case, immediately ventilate and vacate the area, and have your supplier shut off the gas. Call an HVAC contractor to fix your furnace.

If you need furnace repairs, get in touch with Robinson Heating & Air Conditioning. They’re a family-owned HVAC company working out of Middletown, OH, and have served local businesses and households since 1946. To request an estimate, get in touch by phone at (800) 397-8975. More information about their heating and cooling services is available online.