Your furnace has built-in safety checks that help keep you safe. However, when a safety mechanism is triggered, your furnace shuts down, and then your house gets chilly. While this is a good thing for your safety and for the protection of your furnace, it's not good to be cold and uncomfortable. You'll want a furnace repair professional to figure out why your furnace is shutting down too early due to a safety trigger so you can get warmed up again. Here are a few reasons your furnace turns off before it has a chance to warm up your house.
The Furnace Overheats
Your furnace might shut down when it overheats due to restricted airflow and strain on the equipment. A clogged filter can cause this problem, so be sure to check the filter and change it before you call a furnace repair company.
A dirty blower can also cause the furnace to overheat and shut down. If a dirty blower is the problem, you'll probably need a licensed professional to remove the blower and clean it and the motor so the motor and blower fan can work without strain.
The Flame Sensor Is Bad
Another thing that shuts down your furnace for safety reasons is the flame sensor. This small device watches for a flame to ignite once a gas furnace kicks on. If the sensor doesn't detect a flame, it shuts down the furnace so gas doesn't keep pouring in and building up in the combustion area.
When a sensor is dirty or broken, a furnace repair technician has to replace or clean the sensor to get it working again. A more serious problem is when there actually isn't a flame for the sensor to detect. Then, the sensor is doing its job and the repair technician has to figure out why the gas isn't igniting and repair the problem so your furnace is safe to use.
Condensation Backs Into The Furnace
A high-efficiency furnace creates condensation when it operates. The condensation usually drains away without causing any problem, but when the drain line freezes or clogs with algae, dirt, insects, or other debris, the water can't drain.
When water backs up in the furnace, a safety switch turns the furnace off to prevent damage to the equipment. A repair technician fixes this problem by removing the clog and positioning the drain so condensation drains freely.
Different furnace models have different safety mechanisms. New furnaces have improved safety when compared to old furnaces. When your furnace shuts down too soon or shuts down and won't start, you may not know what's wrong. The furnace might be protecting you and the equipment from harm, so rather than run a furnace that isn't working properly, call a furnace repair company to fix the cause of the problem.