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Nordstrom Heating & Air, Inc Blog

Furnace Won’t Turn On? Here’s What It Could Be

Your furnace has a pretty straightforward function, right? It gets cold, the furnace kicks on, and it heats up the house. The thing is, the operation of your furnace is a lot more complicated, so we have to look at multiple reasons why you might need heating repair in Woodinville, WA.

Heating and air conditioning troubleshooting has many nuances to it, so to help you paint a picture of all the potential reasons your furnace isn’t turning on, let’s take a look at some of the more common causes.

It Could be Your Thermostat

Your thermostat is a gauge of your indoor room temperature, but it’s also a messenger for your heater. Your heater doesn’t read the temperature of the room—the thermostat does, then sends an “ON” or “OFF” signal to the furnace to kick on. When it’s time to shut down as the target temperature has been hit, it sends an “OFF” signal.

If your furnace isn’t turning on, the thermostat may be miscalibrated. That means it’s reading the temperature of the room incorrectly. It could be reading it as warmer than it actually is, so when the temperature drops, the thermostat still thinks your room is within acceptable levels. The furnace doesn’t get the “ON” signal, and makes you think the furnace just isn’t working.

The Blower Motor Died

Your furnace’s job is to produce warm air, but then there’s a blower motor that pushes that air through the ductwork in your walls and ceiling, then delivers the warm air to the vents in your home. Without the blower motor, your furnace may be heating air, but it’s not sending it anywhere. This can actually result in the furnace overheating and triggering the safety features, shutting it down prematurely.

Dirty Flame Sensor

Your furnace is trying to turn on, but the flame sensor isn’t detecting anything from the ignition. That’s because soot and debris builds up over time, and your flame sensor gets so mucked up that it can’t tell if there’s a flame or not. When this happens, a technician will have to disassemble the flame sensor, clean each piece, and reassemble it. That should fix the issue.

Air Filter Issues

At the end of the day, a furnace is a forced-air heating system. Yes, your furnace uses combustion to create heat, but as we mentioned earlier, heated air has to be pushed through ducts and vents. In order for that to happen, there’s an air intake with an air filter. When the filter is clogged or dirty, it makes it harder for your furnace to pull air through it, and that can lead to premature shutdowns. Change your air filter once every 30–90 days (depending on filter size and usage) to prevent this problem from happening.

Let’s Take a Look

There’s a lot that can go wrong with your furnace, but your specific problem can’t be diagnosed over a blog post. It needs to be examined by an HVAC technician so they can find out the right course of action. That’s where we come in.

Contact us today to schedule your furnace repairs as soon as possible.

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