Helpful Tips on How to Fix Short Cycling Furnace

Short cycling occurs when your furnace turns on and off more frequently than it should. A properly functioning furnace should typically complete an entire cycle, which lasts about 10-15 minutes, before shutting off.

A short-cycling furnace can be prone to wear and tear, leading to unexpected breakdowns and expensive repairs. It can also result in high energy bills, as the furnace requires more energy to turn on and off repeatedly. This article discusses how to fix a short cycling furnace. 

Before we dive into solutions, answering your "Why is my short furnace cycling" question is essential. Several factors can contribute to this problem, including the following:

Dirty Air Filter

The air filter traps dirt, dust, and other particles in the air, preventing them from entering your furnace. However, with continuous use, this component may become clogged with too much debris, restricting the airflow and causing the furnace to work harder than usual. Due to the extra strain, the furnace may overheat and shut off as a safety measure.

Malfunctioning Thermostat

The thermostat regulates your home's temperature by signaling the furnace to turn on and off. So, if this device is faulty, it may result in short cycling. If you suspect your thermostat has an issue, ensure its batteries are not dead and correctly connected to the furnace. Whenever these two are okay, it could be a sign you need a new thermostat.

Flame Sensor Problems

The flame sensor is a tiny metal rod that detects the presence of the burner flame. When this part is corroded or dirty, it may struggle to function correctly, causing the furnace to short cycle.

How to Fix Short Cycling Furnace

Once you have identified the cause of short cycling in your furnace, it's time to fix it. While you may be able to repair minor issues on your own, other problems may require the help of an HVAC technician. Here are some solutions to short cycling.

Fixing a Dirty Air Filter

If the short cycling is due to a dirty air filter, find your furnace's filter and examine it. Filters in most furnaces are located in the return duct or closer to the blower motor. You may need to change the filter whenever it is visibly clogged or dirty.

You can find furnace filters in most home improvement stores at an affordable price. When replacing the filter, ensure you follow the manufacturer's manual. Incorrectly installing it can reduce its effectiveness, causing your funnel to overheat.

Solving Thermostat Issues

Short cycling resulting from thermostat issues may be due to several factors, including dead batteries, a faulty connection, wrong temperature settings, or the thermostat location. Replace dead batteries and check your thermostat settings, site, and link to ensure they are okay. If the short cycling persists, it may be time to replace the thermostat. When shopping for this item, ensure you purchase one compatible with your furnace with the needed features.

Adjusting a Faulty Flame Sensor

To fix a faulty flame sensor, first locate it. This part resembles a thin metal rod and is found near the burners. Once you see the flame sensor, please turn off your furnace and carefully remove it from its bracket. Examine the sensor for any signs of dirt, corrosion, or damage.

If it is dirty, use fine-grit sandpaper to clean it gently. However, if your flame sensor is corrupted or damaged, you may have to replace it. After finding a solution to the short cycling problem in your furnace, take steps to prevent similar situations. This could entail scheduling regular inspections and maintenance with a reputable furnace repair service. In addition, replace the air filter every 1-3 months, depending on usage. 

When to Call a Professional

If you have tried every tip to fix a short cycling furnace but still can't solve the problem, or aren't comfortable checking the mentioned areas, consider calling a professional. During your call, please provide as much information as possible about the issue and any steps you took to address it.

The furnace repair technician will diagnose and suggest several solutions, including replacing faulty components or performing more extensive repairs. If the furnace is old, they may also ask you to get a new one to save on regular repair costs. 

Reliable Furnace Repair Services At Suburban Heating & Cooling

Following the above solutions can fix short cycling issues and keep your furnace running smoothly and efficiently. However, our Suburban Heating & Cooling experts can help if that seems challenging.

Our team of technicians has the skills, tools, and experience needed to repair any faults, from minor repairs to complete replacements. Contact us today to learn more about our furnace repair services.