What Should You Do if Your Furnace Is Short Cycling

Is your furnace short cycling? And if it is, how can you repair it? Short cycling occurs when a furnace cycles on and off without reaching the set temperature on the thermostat. This condition can prevent your home from heating up to a comfortable temperature. Depending on what’s causing the issue, you may be able to resolve it on your own or require the assistance of an HVAC specialist for furnace service NJ.

Signs That Your Furnace Is Short Cycling

Shorter and More Frequent Cycles

The most obvious sign that a furnace is short cycling is when it has extremely brief cycles that occur frequently. How often does your furnace cycle on and how long do the cycles last? Furnaces that are short cycling typically have cycles that are less than five minutes long, as well as short resting cycles. These cycles can occur anywhere from five to eight times an hour.

Your House Is Cold

If your house is cold it doesn’t necessarily confirm that your furnace is short cycling since inadequate wall insulation, outdated windows, an insufficient furnace, or poor attic insulation can all contribute to a cold house. However, don’t rule out the possibility that your furnace is short cycling.

Temperature Never Matches the Thermostat Reading

Take a look at your thermostat. Does the indoor temperature match the set temperature? If the temperature reading slowly rises but never reaches the temperature set by the thermostat, it’s a sign that your furnace is short cycling.

How to Troubleshoot a Short Cycling Furnace

While some of these furnace issues can be easily resolved, others may require hiring an HVAC technician for a furnace service NJ.

Dirty Furnace Filter

A dirty or clogged filter can cause your furnace to overheat and shut off before reaching the set temperature. The fan on the furnace must be capable of moving a sufficient volume of fresh, cool air over the heat exchanger. If your furnace cycles on for two to five minutes and the air that is coming out of your heat grates is warmer than usual, it may be time to replace your filter. To prevent short cycling from happening again, change your filter every month or two, or as recommended by your HVAC technician.

Faulty Thermostat

The problem may actually be with your thermostat rather than your furnace. The batteries could be weak or dead, or the thermostat itself could be defective. First, try switching out the batteries. If that doesn’t work you can try checking the thermostat’s settings to see what the temperature is set to. If the temperature is too high, your furnace will frequently cycle on. Fortunately, you can fix this by lowering the temperature differential.

Blocked Flue

The furnace flue is designed to expel deadly carbon monoxide. If it is clogged or blocked, hazardous gasses will leak into your home, which is extremely dangerous. The most common causes of a blocked flue are bird nests, beehives, and leaves. You can resolve this by turning off the furnace, detaching the flue, and clearing any obstructions. You may need to call animal control or pest control if you’re dealing with a nest or beehive. Then reassemble the flue and restart the furnace.

Faulty or Dirty Flame Sensor

If your furnace flame shuts off immediately after the burner fires, your flame sensor could be faulty or dirty. The flame sensor tells the furnace that a flame is present while the gas valve is open. If the sensor doesn’t sense a flame it will shut the furnace off. However, if the flame sensor is dirty or not working properly, it could either shut the furnace down or keep it running, causing deadly gas to build up in your home. Fortunately, this is an easy fix. If your flame sensor is dirty, you can clean it; if it is faulty, you can get it replaced. Cleaning a flame sensor is pretty simple and if you’re handy, you can do it on your own. Otherwise, don’t hesitate to reach out to a reputable HVAC technician for this furnace service NJ.

When to Call a Professional

Most furnace short cycling problems should be handled by a professional HVAC technician, unless you're dealing with a dirty furnace filter, resetting your thermostat, or changing its batteries. If you’re looking for a furnace service NJ from a reliable HVAC company, reach out to Quick Serve Pro. We have been providing New York and New Jersey residents with top-rated HVAC services for almost 30 years and have built an outstanding reputation in the process!