When the snow is blowing and your furnace gives out suddenly furnace problems occur, knowing that the failure was likely preventable is a bit of a “cold comfort”. The best way to prevent furnace failure and subsequent freezing is by routinely checking your furnace before the cold season hits each year.
The Common Furnace Problems
Your Furnace Keeps Turning on and Off
As a furnace heats your home, it typically cycles on and off, trying to maintain the temperature set on the thermostat. Depending on the programmed temperature and the outdoor temperature, a furnace might cycle on, heat the room or home to the desired temperature, then cycle off again several times an hour.
If a furnace starts short cycling or turning on and off frequently, without ever reaching the set temperature, that is usually a sign that something is wrong. During a short cycle, the furnace will only run for a couple of minutes before it turns off again. Often, the cause of a short cycle is a lack of airflow in the furnace, which causes it to overheat. Furnaces have safety switches built-in that will shut down the system if the temperature gets too hot.
A clogged air filter can restrict airflow, leading to overheating and the safety switch going off. If you notice that your furnace is turning on and off frequently or is only running for a couple of minutes at time, never heating up to the desired temperature, your first step might be to check and replace the air filter. If replacing the air filter does not resolve the issue, you will need to call a technician to take a closer look.
IGNITER
Due to normal wear and tear, often the igniter will go out. This is a component that endures constant expansion and contraction and really high heat, failure is pretty common. They are also susceptible to power surges, which can also cause them to fail.
The average furnace turns on 4-5 times per hour, that means over the course of a season, the igniter is undergoing a lot of stress. We recommend getting a diagnosis from a licensed HVAC technician to know that the igniter is the culprit first before attempting to replace it yourself.
Air Leakage
Perhaps your furnace is running, the ducts are clear, you’ve checked all the switches, but you’re still not getting the warm air that you should be. It could be that there is an air leak somewhere in your system.
If the warm air is heading outside instead of heating the house, your home will be a bit cool. Or, if there is a draft (perhaps one that you cannot feel directly) then too much cold air could be coming in. Complete a thorough check of the interior and exterior of your home to determine if this is the case.
