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Nordstrom Heating & Air, Inc Blog

This Means Your Furnace is in Dire Need of Repair

When winter bites, your furnace bites back harder. It heats your whole home quickly, allowing you to live out your day without shivering in the living room. It’s usually reliable, but now when you turn your furnace on, it doesn’t heat your home quite right. Now it’s starting and stopping before reaching the target temperature.

It’s something called short cycling, and it means you need furnace service in Bellevue, WA. But what is short cycling, and how can you fix it? Is it really a huge red flag? Don’t worry; we’ll answer all your questions right now.

Here’s What Short Cycling Does

Your thermostat communicates with your HVAC system. The thermostat detects the temperature of the room, then it sends a simple on or off request to the HVAC system. When this happens, the heater (in this case) turns on until the thermostat says “Okay, that’s enough, we’ve hit the target temperature.”

The time from the furnace receiving that request to when it receives an off request and ceases operation is referred to as one heating cycle. A short cycle is when your furnace starts up, shuts off, but doesn’t complete its goal.

Now your furnace keeps firing up, shutting down, and running for more time than it’s supposed to. It’s struggling to reach its goal, and that’s an enormous problem.

So What Causes a Furnace to Short CYcle?

Furnaces are combustion-based machines. They have a live flame, called a pilot light, that’s activated by an electronic ignition system. When the furnace receives the signal to turn on, it creates a flame, supports it, and in a nutshell, uses this as the catalyst to heat your home.

Your furnace has a flame sensor so it knows when there’s a live pilot light. If it can’t detect a live pilot light, it turns off and stops using the gas line. This is to prevent gas from leaking into your home and causing health problems or a risk of explosion. The flame sensor’s job is very important.

But it can run into trouble. When your flame sensor is dirty with soot, dust, or simply hasn’t been tuned up in a while during a routine maintenance appointment, the sensor can’t properly detect the flame. This isn’t the only cause for short cycling, but it is a common one. If your furnace shuts down right away after firing up, this is likely why.

A technician can either clean the flame sensor and detect if it’s working properly, or replace the sensor if it simply ran its course and doesn’t work anymore. Either way, it’s not a DIY kind of job.

Don’t Delay Furnace Repairs

Your furnace is telling you that it needs repairs. Short cycling leads to larger problems down the road, but the fact that your furnace can’t even heat your home now is a big enough red flag. Call us today and we’ll diagnose and repair whatever the cause of your furnace’s short cycling is.

Contact us today to schedule your furnace services as soon as possible so you don’t have to worry about heating this winter.

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