Why Do HVAC Systems Break Down During Extreme Weather?

An HVAC system tends to break down or fail to perform effectively during extreme weather because these conditions push the equipment beyond its normal design limits. Most residential HVAC systems are engineered for typical seasonal temperatures, so if we have prolonged extreme highs or lows here in San Antonio, this can be too much for the system, and you end up having to make HVAC repairs.

Why HVAC Systems Break Down During Extreme San Antonio Weather

Extreme Heat

Air conditioners work by moving heat from indoors to outdoors, so in very hot weather, this process becomes much harder. The system just doesn’t get any breaks when the temps soar over about 95°F and stay there continuously. This often leads to overheating of key components like the compressor, fan motors, and electrical parts. Overwork can also cause the compressor to seize or lead to a blown capacitor or thermal shutdown.

Standard AC units are typically designed to cool your home to about 20°F below the outdoor temperatures. If it’s 105°F outside, the best they can realistically achieve indoors is ~85°F, even running full blast, but most people would prefer temps to be closer to 70°F. Trying to force that overloads the system.

A final piece of the puzzle is if you haven’t had proper service on your HVAC. The restricted airflow from dirty filters or coils or low refrigerant levels can cause the coils to ice up, which blocks its cooling power entirely.

Extreme Cold

Heating systems face different challenges, especially heat pumps, which extract heat from outdoor air. Heat pumps lose their efficiency dramatically when temps go below 40°F, and especially when they go below 25°F. There’s very little heat left in the outdoor air to extract. Below 0°F, many standard heat pumps struggle significantly or switch to less-efficient backup electric resistance heating.

On regular HVAC systems, moisture on the outdoor coils can freeze, which blocks the airflow and stops heat transfer. The defrost cycle may fail or not keep up, and then the system shuts down or just blows cold air. Gas furnaces end up running longer cycles in the cold, and, again, if maintenance isn’t on point, then dirty filters and restricted airflow will strain the whole system.

Importance of Maintenance

Many breakdowns happen because underlying issues get exposed when the weather turns nasty, in either direction. If the air filters and coils are dirty or clogged, you get restricted airflow, overworking units, and overheating or freezing. When refrigerant levels drop because of leaks, you get poor heat transfer.

When the equipment is old and unmaintained, the worn-out parts are the first to fail. And if you already have either an oversized or undersized unit or poor insulation, the inefficiencies will be multiplied by extreme temps.

Call Us for HVAC Repairs and Maintenance

Extreme weather doesn’t usually “break” a well-maintained system, but it does accelerate wear, reveal neglect problems, and push the components past their safe operating limits. That often results in failure when you need the system most, especially if you haven’t been maintaining it. For everything you need so you can rely on your HVAC system in any weather, call Beluga Air now in San Antonio.

Tags: air conditioning service, hvac repair, Maintenance
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