How Strong Is the Smell?
Natural gas is odorless, but utility companies add a chemical called mercaptan, which smells like rotten eggs, to make leaks easy to detect. While mercaptan itself isn’t harmful, its smell signals potential danger. Unfortunately, odor strength can be misleading—it may be masked by other smells or absorbed by surfaces. Even if the odor isn’t overpowering, a persistent smell should be treated as a red flag.
How Long Does the Smell Linger?
When furnaces sit idle through summer, dust can settle inside. When you first fire up the unit, this dust burns off, sometimes mixing with mercaptan and creating a temporary gas-like smell. If the odor fades within a minute or so and doesn’t return, it was likely just dust burning off. If the smell lingers or reappears, it may indicate a leak that needs attention.
Where Is the Smell Coming From?
The most common place you’ll notice gas odor is near the furnace itself. A faint smell during ignition isn’t unusual, as the furnace may ignite several times per hour in cold weather. However, if the unit is short cycling—turning on and off without reaching the set temperature—this could be the cause and should be checked by an HVAC technician.
Gas smells can also point to exhaust system problems. If venting isn’t working properly, small amounts of gas may back up into your home. While not usually an emergency, this situation still requires prompt repair to prevent worsening issues.
Stagnant and Consistent Gas Smell
If the odor grows stronger or spreads beyond the furnace area, you may have a gas leak. In this case:
- Leave the home immediately.
- Do not flip switches or use electronics. Sparks can ignite gas.
- Call emergency services and your gas company from a safe distance.
Once the leak is secured, your furnace and gas lines will need to be professionally inspected and repaired.
If the smell is contained to a small area, you can carefully shut off the main gas supply before calling for service. The shut-off valve is typically located near the furnace or outside the home. Once the gas is off, ventilate the space by opening doors and windows while you wait for professional help.
What to Do for Repairs
After the immediate danger is handled, call Blue Best Plumbing, Heating, Air, & Generators. As a locally and women-owned and operated HVAC company, we proudly serve Bountiful and the surrounding areas with expert furnace repair, inspection, and maintenance. Our certified technicians will locate the source of the issue, provide an honest estimate, and complete repairs quickly and safely.
In addition to furnace services, we also handle AC systems, fireplaces, and indoor air quality solutions to keep your home safe and comfortable year-round.
If your heating system needs repair work, or it’s simply time for routine maintenance, don’t hesitate to give Blue Best Plumbing, Heating, Air, & Generators a call today to schedule an appointment.
