Is Your Furnace Short-Cycling?

homeowner wrapped in blankets due to malfunctioning heating system

The arrival of winter means cold and uncomfortable temperatures. Make sure that you and your family are warm despite the frigid weather outside. Inspect your heating system so you can be sure that it is in excellent working condition. Depending on the issue, it could be an easy fix or a complex one. One such example is short cycling. This issue is when your furnace runs then shuts off and starts again repeatedly in quick successions. Therefore, a professional HVAC contractor should look into it immediately.

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Is My Furnace Short Cycling?

A furnace works by turning on and running until the set thermostat temperature is achieved. After that, it will turn off and let the space maintain the heat level. The furnace will need a while until it needs to restart again because the area is getting cold. In contrast, a short cycling furnace operates on a short series of turning on and off. This not only results in your furnace failing to reach the set temperature, but it also causes wear and tear. Your house will also feel cold even though your furnace has been running all day.

What Causes Furnace Short Cycling?

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Short cycling needs to be addressed as soon as possible. Determining the cause is the first step to finding the right solution. Some of the few reasons that trigger short cycling include:

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Overheating Heating System

Overheating is usually caused by restricted airflow. As a protective measure, HVAC systems are equipped with damage protection features. This allows your furnace to detect if your furnace is getting too hot. If it reaches a dangerous heat level, the unit will switch off automatically. This way, heating system damage is prevented.

The damages your system could incur include heat exchanger cracks where carbon monoxide can leak through. It can be a potentially lethal substance so having this feature in place is significantly helpful.

Bad Furnace Flame Sensor

gas furnace that isn't working properly

If the flame shuts off as soon as it lights, you might be dealing with a bad furnace flame sensor. The sensor monitors the gas valve so that raw gas doesn’t leak into your home. It also switches the valve off when there is no flame. A faulty sensor switches off the gas valve, although it is needed. The sensor might be dirty, so cleaning it might do the trick. However, if it needs replacing, have a professional HVAC technician do it for you.

Exhaust Vent Is Blocked

Exhaust vents must be open at all times. However, blockages can happen. Insects might have built their nests in the vents, vegetation might have grown over it, or snow might have piled high and covered the vents. Check the vents regularly to ensure that it is not obstructed. Anything that is blocking your vents should be removed immediately. Seek the help of animal control if a dangerous animal is blocking the vents.

Furnace Filter Is Dirty

HVAC air filter replacement

Furnace filters trap contaminants from getting distributed in your house. It can get clogged over time, and this can result in short cycling. It can also lead to hotter air pumping out of your heat grates. A dirty furnace filter restricts proper airflow, which then prevents your furnace to cool down properly. The heat will build up and cause overheating, so your furnace will switch off as a protective measure. Replace disposable filters and clean washable ones periodically to prevent this problem.

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Heat Grates Are Blocked

Warm air is released via the heat grates. If the hot air does not flow freely, the heat gets trapped in the system and causes overheating. It will then lead to short cycling. Heat grates have dampers that allow you to control whether a room gets warm air or not. It helps make your home more energy-efficient. Just remember to have at least 75 percent of all vents open at all times to keep your heating system from overheating.

Thermostat Is In The Wrong Spot

programmable thermostat

Thermostats have built-in sensors to determine the indoor temperature. This way, your thermostat can regulate furnace activity. However, a thermostat that is in the wrong spot might not work as it should. Putting it near a direct heat source, such as a sunny window, a heating grate, or lamp, for example, will affect the sensor readings. The thermostat will gauge that the house has reached the set temperature and switch the system off even if it is not the case. Ensure that the thermostat is in a neutral spot so that its temperature readings do not get skewed.

Oversized Furnace

It might be tempting to go for the largest furnace you can get your hands on. However, remember that having a bigger furnace doesn’t mean it is the best for your home. A furnace that is too large will result in short cycling.

Some of the consequences of an oversized furnace include faster wear and tear, higher-than-usual heating bills, and cold and hot spots around your home. Unfortunately, the solution to having an oversized furnace is to replace it with one that is of the correct size. Professional HVAC techs can help you by conducting precise calculations to determine the perfect size for your home.

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Ensure that your home is comfortable during winter by checking your furnace. If it is short cycling, look into the underlying reason using the clues above. Contact your local trusted HVAC company to conduct proper diagnosis and repairs. This way, you can enjoy a stress-free cold season and a longer-lasting furnace.

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Call R.F. Ohl For All Of Your HVAC Requirements

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For all your heating and cooling service needs, do not hesitate to contact R.F. Ohl. We have the best professionally certified and trained HVAC technicians. They can conduct high-quality HVAC services, including furnace repairs, AC repairs, ductless installations, boiler replacements, and more. Each of our friendly technicians is knowledgeable and experienced in performing correct HVAC services at all times.

Rest assured that our company offers the most competitive heating and cooling service prices in the area. Our tune-up services help improve comfort, energy efficiency, and cost-effectiveness. We can also assist you should you need a replacement HVAC system. We can recommend the most suitable make and model for your home and budget. Your satisfaction, home comfort, and efficiency are our top priorities. All our work is backed with a guarantee. Call R.F. Ohl today for a free, in-home estimate.

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