Does your furnace work fine during the day but stops working at night? On a very cold night, a cycling furnace can become more noticeable because the house is losing heat faster than it does during the day. That means your heating system is forced to run longer to keep up.

When that happens, small problems that remain hidden in milder conditions can start to show themselves. Weak ignitors, clogged filters, dirty flame sensors, thermostats with weak batteries or airflow problems may not always cause a total daytime breakdown — but they can absolutely create trouble overnight when the furnace is under more strain.

This heating repair contractor in Willowbrook, Illinois is going to explain more below.

What should you check first if your furnace stops working at night?

A professional heating repair contractor in Willowbrook, Illinois will usually start with the basics before assuming the furnace needs a major repair. 

Thermostat settings are one of the first things to check. Make sure the thermostat is properly set to heat and that it is getting power. If the display is blank, that could mean dead batteries or another electrical problem. The thermostat could also fail to communicate properly at the times your furnace needs to run the most.

Airflow is another major early checkpoint. A dirty or clogged air filter can restrict airflow enough to cause the heat exchanger to overheat. As a result, the furnace may shut down before it finishes a normal heating cycle.

The same thing can happen if too many supply or return vents are closed off or blocked. These airflow problems can have a major impact on your furnace performance, especially overnight when the system is working longer.

Could venting or ignition problems be stopping your furnace at night?

Once the obvious issues are ruled out, your heating repair contractor in Willowbrook, Illinois will check the furnace itself. That is where you will find the real cause.

One common issue is overheating. Furnaces have a safety device called a limit switch that shuts off the burners if the system gets too hot. This is meant to protect the furnace from damage.

If airflow is restricted, the furnace can overheat and shut itself down as a safety measure. That is one reason a furnace may run for a while and stop during the night.

Venting problems can also become more noticeable after dark. If a furnace cannot get the fresh air it needs, or if it cannot safely exhaust combustion gases, it could shut down. This is not something to ignore because blocked venting can create serious safety risks, including carbon monoxide danger.

During winter, snow, ice, leaves, debris or other obstructions around the intake and exhaust pipes can interfere with operation. This is especially true on high-efficiency furnaces that vent through sidewall pipes. A furnace can run fine earlier in the day, then struggle later as outdoor conditions change.

Ignition lockouts are another possible explanation. In some cases, the furnace tries to ignite, fails and then goes into a hard lockout mode for safety. That can happen because of a dirty flame sensor, a faulty ignitor, overheating, a clogged filter or blocked vent pipes.

Looking for a heating repair contractor in Willowbrook, Illinois?

Do you need to have your furnace looked at by a professional? If so, and if you’re looking for the top-rated heating repair contractor in Willowbrook, Illinois, look no further than Hearthstone Heating & Air Conditioning. Our licensed technicians can diagnose the root cause of your nighttime furnace problem and restore safe, reliable heat to your home. Contact us anytime at (630) 435-9800 to get started.