Winter HVAC Repair: 3 Common Causes

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When your heat stops working on the first genuinely cold night of the year, it's rarely a mystery once a technician takes a look. Here are the three causes we see most often — and what each one means for you.

1. A System That Sat Unused Too Long

Heating systems that go months without running can develop small issues that only show up once you actually need them — a thermostat with dead batteries, a pilot light or ignition component that needs attention, or dust that's built up inside the unit over the off-season. None of these are usually serious, but they do explain why a system that "worked fine last winter" suddenly won't start.

2. Thermostat Problems

A surprising number of "no heat" calls turn out to be the thermostat, not the furnace itself. Dead batteries, a system accidentally left in cooling mode, or a fan setting stuck on "on" instead of "auto" can all make it look like your heating has failed when the actual furnace is working fine. It's always worth double-checking your thermostat settings before assuming the worst.

3. Airflow and Filter Issues

A dirty or clogged filter restricts airflow enough to trigger safety shutoffs on some systems, or simply reduces how much heat actually makes it into your rooms. This is the most preventable of the three causes — a filter that's changed on a normal schedule rarely becomes a mid-winter emergency.

What to Check Before You Call

If your heat isn't working, start with the simple stuff: confirm the thermostat is set to heat mode with a target temperature above the current room temperature, check that the breaker for the system hasn't tripped, and take a look at the filter. If all of that checks out and you're still without heat, it's time for a professional diagnosis rather than guessing further.

We're Here When You Need Us

A cold house in the middle of winter isn't something that can wait. Call Blake & Sons for heating repair and we'll get your system — and your home — back to comfortable.