Guide for Troubleshooting Gas Furnace Problems

In the cold winter months, we rely on a gas furnace to warm up our homes. There is no doubt that heating consumes maximum energy (about 30 - 35 percent) in every home. Using an energy-effective gas furnace helps in reducing the expenses, as well as contributes a bit in conserving energy. However, it is obvious that any type of gas furnace model faces problems with regular usage and it requires repairing.

Before discussing the problems, let's try to understand the working of a gas furnace. It is a device that resembles a large box. Inside the box contains an air filter, gas burner, thermostat, induced draft fan, and circulating fan. As cold air is taken inside the furnace, it is filtered by the air filter.

The filtered air is heated with the help of the gas burner, which is then circulated to the rooms with a blower motor. After heating the rooms, cold air is again returned to the gas furnace, via the ductwork. Thus, the cycle of cold air converting into warm air continues to liven up the rooms.

This is the most commonly faced problem with a gas furnace. There are two possibilities of heat production problem; no heat production or insufficient heat production. The former case may be caused due low setting of thermostat and/or thermostat breakdown, blown fuse (or tripped circuit breaker), and pilot light defect.

For troubleshooting this problem, clean the thermostat and check its settings. If the problem is in the circuit breaker or fuse, you can replace them. Insufficient heat production may be due to dirt accumulation in the air filter or air burner. Clean these parts and try readjusting the gas burner.

If the pilot light goes off, it may be due to a problem in the drafts. You can troubleshoot this problem by following the manufacturer's instruction (often attached to the furnace). In case, there are no instructions, you can follow some simple tips to relight the pilot light such as adjusting the pilot setting, cleaning the pilot light opening, and replacing the thermocouple.

These problems are often caused due to dirty air filter and problem in the thermostat or blower motor. To repair any problem in these furnaces, check the thermostat.

Try adjusting the heat anticipator and clean the air filter. If required, replace the air filter with a new one. In case, the problem is in the blower motor, you can lubricate the shafts. Also check the belt; a too loose or too tight belt can also cause these problems.

Though a gas furnace is installed with a control shutoff system to avoid gas leaks, there are still possibilities of gas leakage. If you suspect the same, prepare a soapy solution by mixing liquid detergent and water. Apply this in the gas supply line and valves.

If the soap water bubbles at a certain point, then you can confirm a gas leak problem. You can try tightening the area with a pipe wrench or call a serviceman.

If you smell gas, it is advisable not to turn on the gas supply or touch any component of the device. Instead, come out of the house and report the gas leak to the fire department or gas company as soon as possible.

This was a brief guide for troubleshooting gas furnace problems. In case, you are not familiar with the device, it is always better to call a serviceman as there is a risk of fire and/or explosion, especially in furnaces with electronic ignition.

Irrespective of the brand, regular servicing of the furnace unit is advisable to ensure proper functioning and also, to protect oneself from unwanted accidents.