What is Wrong with a Furnace if it Keeps Cycling On and Off

Why Your Furnace is Short Cycling and Ways to Fix It

When a furnace is short cycling, it switches off prior to getting to the wanted temperature level, or it cuts on and off too often. It isn’t usually dangerous to you or your family’s wellness. However, if not dealt with and fixed, it can be inefficient and damaging to your heating and air system. To assist you in preventing damage and added cost to your system, we’ve put together a list of factors that may be what is wrong with a furnace if it keeps cycling on and off and ways to fix it.

Your Furnace is the Wrong Size

When it comes to your heating system size, bigger isn’t always better. A heating system needs to be the appropriate dimension for a home or else there will be irregular heating cycles and temperature problems. If your heating system is turning on for just 3-7 minutes at once, it’s probably a larger-than-needed furnace for your home or property. Your home will be freezing one moment, too warm the next, and after that back to freezing. This can add up to a utility bill that is higher than anticipated.

Blocked Exhaust Vent

If your heating system is switching on for just 1-5 minutes at a time, the possibilities are it’s a clogged exhaust vent. This can pose a possible hazard to the safety of your house. With a blocked air vent, carbon monoxide gas has nowhere to go. The gas might leak out of the heater and right into your house. The usual sources of a blocked exhaust vent consist of bird or animal nests, beehives, or ice or snow.

Harmed Flame Sensing Unit

Flame sensing units, additionally referred to as flame rods, are designed to find the existence of a flame in the furnace. It is a short, thin metallic rod that senses and verifies that there is a fire burning in the furnace.

If your flame-sensing unit is malfunctioning, your heating system will frequently cycle on and off. It will basically be turning itself off as quickly as it lights. Your furnace turns on for only seconds each time is possibly due to an old or malfunctioning flame-sensing unit. This is among the more usual reasons for short cycling. In some cases, all that needs to be done is clean the flame sensor and your furnace should be back to running like normal. If that does not work, after that it’s possibly time to call a professional.

Contaminated Air Filters

For heaters that are just switching on 2-5 mins each time, the answer could be to check your heating system filter. Dirty heating system filters can lead to an overheated furnace which will then turn off before your home is warm. One more indicator that your filter could be the main issue is if the air blowing from the furnace is actually hotter than it should be. Simply clean or change the filter if this is the problem.

Air Vents are Shut

Likewise, shut heat vents could be a simple, overlooked answer, yet be causing your furnace and system to run too hot, causing it to cycle off too quickly. While a dirty or clogged air filter does not allow adequate air in, heat vents that are shut do not let the air out. If your heater runs every five minutes, then shuts off, then runs again, then this could be the problem. This has a very easy fix – merely check and see that 75 percent of your heat grates’ dampers (the vents in each space) are open.

Knowing the Right Number of Times a Furnace Cycles Per Hour

When working appropriately, a furnace should go through two or three cycles per hour. Commonly, furnace cycles often tend to be this long in order to properly heat up a residence and keep it near the temperature setting you set.

A heating system cycle is when a heater turns on to heat up your home and it shuts off once the desired temperature is attained. The length of your furnace’s home heating cycle depends on how cold it is outside. The lower the outside temperature, the longer the cycle span. Home heating cycles may be anywhere from 10-15 minutes.

Negative Results of Furnace Short Cycling

Correct, efficient cycling protects against a heating system continuing to run and heating up a home or space more than what’s wanted. However, if a full cycle doesn’t finish as it should, it’s cutting into your system’s efficiency and adding to your utility bill.

A short cycling heating system can have more severe impacts as well. It’s uncomfortable, maybe even unhealthy, for you and your family. It wears down all the parts of a heating system at a faster rate. This can lead to more troubles and the need for upkeep on your HVAC system in the long run. The longer a furnace is short cycling, the shorter the furnace’s life expectancy gets.

At South End Heating & Air we specialize in furnace repair, call us for a free consult. We’ll evaluate your system and help make recommendations for optimum value. After all, we want to keep you cool all summer long and warm in the winter. Just schedule a visit with one of our technicians to talk about how we can help with your heating needs. Would you like to learn more options our techs can help you with? give us a call 704-684-5339