Is It Normal to Smell Gas Near a Furnace?

Many furnaces used in the Greater Glendale area run on natural gas or even propane. Both of these gases are odorless in their natural state. Since that can be quite dangerous if there is a leak, your local provider adds mercaptan, which smells like rotten eggs. A common question among homeowners regarding their furnaces is whether or not a gas smell is normal. The answer to that question depends, so with that in mind, let us explore the situations where you could and should not smell gas.

Potential Gas Leak

While serious gas leaks related to your furnace are not common, there is the potential, so let us begin with the most dangerous scenario first. If you detect a strong and persistent gas smell emanating from the furnace, your vents, or another source in the home, disable your furnace via the thermostat immediately. Open windows, turn off the main gas valve, and leave the home. You should then call your gas company. If you do not have that number handy, call your local fire department. If a gas leak is detected, you will need to schedule an emergency repair with your local HVAC company. If a leak was not identified, it is still a good idea to schedule an inspection and maintenance as soon as possible.

Dust and the New Cold Season

The first time you operate your furnace after a period of disuse, it is perfectly normal to smell gas. The smell may even be rather strong, but it should only last for a few minutes. If the smell is not temporary, then this can be an indication of a more serious problem. The reason this happens is that during the period of inactivity dust accumulates in and on your heating equipment. When you start your furnace for the first time in a while, not only do you experience the expected gas smell that comes with cycling—discussed in the next section—the dust is heated and burned away, which exacerbates the smell that comes from the mercaptan. Regular maintenance and duct cleaning will minimize the presence of dust and therefore the effect. In addition, the first time you run your furnace each season should ideally be performed by a professional.

Regular Gas Emissions

It is also perfectly natural for your furnace to emit a small amount of gas each time it cycles—or turns on. If you smell it occasionally and tend to have to sniff around when you do, this is normal. Some people are most sensitive to smell than others, so take that into consideration. This natural gas emission can be problematic if your furnace is cycling too often—an issue known as short cycling. However, in such cases, the gas is a symptom of another problem. If you experience this or are simply concerned about the gas you do smell, it is best to schedule an inspection as soon as possible.

Check Trash and Compost

Be mindful that the mercaptan added to natural gas is sulfur-based. There are other sources in your home that can produce similar smells, which you can then mistake for your furnace. A trash bin with food that has begun to decay is a common culprit and should be removed from the home. Your garbage disposal may also be the source, which can be eliminated with a vinegar and baking soda solution. Compost is another potential cause. While compost is generally maintained outdoors, smells can easily enter the home through windows, doors, cracks in walls and foundations, and so forth.

Furnace Exhaust

It is also possible that your heating system is exhausting gas that is blowing back into the home. This is similar to the potential problem with compost discussed above. Your system has an exhaust pipe that is necessary to expel used gas. No system is totally efficient. There will be unused gas in that mixture that will still have the smell due to the mercaptan. Identify where your exhaust pipe is located and determine if there is the potential for that exhaust to reenter the home. If there is, the fix may be as simple as not using a particular window or another lifestyle change. Your local HVAC company can also help by lengthening the pipe, diverting the exhaust or—in the most extreme case—moving the exhaust pipe.

Have an Inspection Performed

When it comes to the potential for a gas leak in your home, it is better—as the old adage goes—to be safe than sorry. If the smells you detect make you uncomfortable, schedule an inspection. Your HVAC technician can conduct a comprehensive examination and determine what if anything is causing the smells. Many heating companies also specialize in indoor air quality. If the furnace inspection reveals nothing, then it is possible to evaluate the air throughout the home in order to find potential issues.

Install a Carbon Monoxide Sensor

Although uncommon in homes, with a serious gas leak there is the potential for explosions and fires. In most cases, however, the risk associated with furnace gas leaks is reduced indoor air quality that can be harmful to your health and even lethal in the direst cases. This is the reason that the installation of carbon monoxide detectors with gas furnaces is code in most jurisdictions. If there is a serious carbon monoxide presence in the home, your detector will alert you long before your nose can if it can tell at all. If you want greater peace of mind, you may also want to invest in a more robust indoor air quality monitor. There are sophisticated smart thermostats on the market that provide humidity control and monitor indoor air quality and can even send notifications to your phone based on the data being collected.

Schedule Routine Furnace Maintenance

Seasonal maintenance is necessary to uphold warranty coverage in most cases. It is also recommended because it helps avoid increases in monthly energy costs and extends the lifespan of a furnace. But routine maintenance also provides you peace of mind. If a trusted technician performs a multipoint inspection each season, then a faint gas odor here or there is no cause for concern. Seasonal HVAC maintenance is relatively inexpensive, and most heating and cooling companies offer maintenance programs that help you save even more while getting the regular examination, cleaning, and upkeep that your equipment requires.

Your Glendale Area Furnace Pros

Christian Brothers in Glendale is proud to have served the Greater Phoenix area for more than 40 years. One of our specialties is furnaces, and we have highly skilled and experienced heating technicians who can inspect your heating equipment and diagnose any potential issues. Our team installs, maintains, and repairs all manner of cooling and heating equipment. You can also rely on our company for a full range of plumbing services, including drain cleaning, burst pipe repair, and tankless water heaters, and a full range of electrical services, including lighting installation, panel box upgrades, and rewiring.

Call Christian Brothers today or contact us online with questions or to schedule an appointment.