Guide for Troubleshooting Gas Furnace Problems

In cold winter months, we rely on the gas furnace to warm up our homes. There is no doubt that heating consumes the most energy (about 30-35 percent) in every home. Using an energy-effective gas furnace helps in saving money, as well as contributes a bit in conserving energy. However, it is common that any type of gas furnace faces certain problems and requires repairing. Before discussing the problems, let's try to understand the working of a gas furnace.

A gas furnace is a device that resembles a large box and consists of an air filter, gas burner, thermostat, induced draft fan and circulating fan. As cold air is taken inside the gas 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. A defect in any of the parts results in gas furnace problems. Following are some of the common gas furnace problems and a guide on how to troubleshoot them.

Problems in Heat Production: This is the most common problem of gas furnace. There are two possibilities of heat production problem; no heat production or insufficient heat production. The former problem 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 and check the thermostat settings. If the problem is in the circuit breaker or fuse, you can replace them. Insufficient heat production may be due to dirt in the air filter or air burner; clean these parts and try readjusting the gas burner.

Pilot Light Problem: 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.

Frequent Switching On and Off of Gas Furnace: This gas furnace problem is often caused due to dirty air filter and problem in the thermostat or blower motor. To troubleshoot this problem, check the thermostat; try adjusting the heat anticipator and clean or replace the air filter. If the problem is in the blower motor, you can lubricate the shafts. Check the belt; too loose or tight belt can also cause this gas furnace problem.

Gas Leakage: Though a gas furnace is installed with a control shutoff system to avoid gas leaks, there are still possibilities of gas leak. If you suspect a gas leak, prepare a soapy solution by mixing liquid detergent and water. Apply this mixture in the gas supply line and valves. If the soap water bubbles at a certain point, then you can confirm the gas leak. You can try tightening the area with a pipe wrench or call a serviceman. If you smell gas, it is advisable not to turn off 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.

If you are 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. Regular servicing of the gas furnace is advisable for proper functioning of the appliance and to protect oneself from unwanted accidents.