A Quick Guide to Furnace Troubleshooting & Repair for the Future Gas Technician

Gas technicians get plenty of calls during the winter months when homeowners encounter issues keeping their homes warm. Furnace problems should always be handled by a certified heating, ventilation, and air conditioning (HVAC) professional who holds a gas technician certification. Gas technician courses teach students how to deal with the challenges of installing, servicing, and maintaining gas-fired equipment for residential, commercial, and industrial uses through exciting hands-on training.

That means that if you decide to pursue HVAC training, you’ll likely work with residential furnaces often throughout your future career. To help you get started, here are a few points to keep in mind when troubleshooting and repairing some common furnace issues.

A Brief Overview of How a Furnace Works for Future Gas Technicians

One of the reasons why certified gas technicians are in such high demand is because furnaces use combustible fuel to heat homes and therefore need to be handled professionally and with care.

Furnaces turn on when the thermostat detects the temperature of a home dipping below a set level. That’s when it sends a signal to the furnace that it’s time to turn on. When the furnace turns on, a burner inside the combustion chamber of the furnace begins to emit fuel (usually natural gas or propane), which is then lit by the furnace’s pilot-light (a small flame that is always on inside the furnace), in order to begin burning and producing heat. The burner then produces heat inside a separate heat exchange chamber which is filled with air from the home. This air is later pumped back out of the chamber once warm. Various aluminum channels, called duct work, carry the warm air all around the house. Finally, return vents suck the now cool air back to the furnace to be re-heated and redistributed.

Gas Technician Course Students Will Learn How to Fix Pilot Light Problems

Pilot lights are one of the first things you should check if ever you encounter a furnace problem as a gas technician. A few common issues with pilot lights are that the light’s orifice (the place where a small amount of gas comes from to keep the flame lit) is clogged or the flame is set too low.

To unclog the orifice, turn off the furnace’s gas and take a thin wire to poke around inside the pilot light’s housing. This will help knock free any debris that may be obstructing the flow of gas. Check the pilot light’s flame level by adjusting a small screw that is next to the flame which controls how much gas the flame receives. Usually, the flame should remain around 3.5 to 5 centimeters high.

Gas Technicians Keep Homes Hot and Homeowners Happy

If a home is warm, but not warm enough, there are a series of steps students in a gas technician course will learn to follow in order to troubleshoot this issue.

First, be sure that nothing is obstructing the flow of warm air by checking all the vents and registers—the place where the warm air is supposed to be coming from—in order to ensure that the air has a chance to flow properly. Second, check the thermostat to make certain that it is indeed set at a high enough temperature to signal the furnace to work properly. Third, check the filters in the furnace to make sure they aren’t dirty and blocking air flow. These are usually located in the blower department of the furnace, which can be located based on the fan noise that it emits, or inside the giant pipe that stems from the furnace to bring warm air back into the home.

Check the furnace’s filter to make sure debris isn’t blocking warm air from getting through
Check the furnace’s filter to make sure debris isn’t blocking warm air from getting through

Warming up to a gas technician career?

Contact an advisor to find out how PAT can help you get started on this rewarding career path.

Are You Career Training Ready? Find Out!
Take the "Career Exploration Kit"

This fun, online quiz takes 3-minutes to complete and you’ll get a personalized report. Identify your strengths and social style, plus the training and positions you’re best suited for. Get Your Career Readiness score now

Take the Career Exploration Kit