As an HVAC service company, fall is the time of year when we start getting calls about odd heater behavior. After all, it’s been several months since most heaters have gone through heavy use, so you might find that yours is doing something that you don’t remember it doing before.

Below, we’ve put together some of the most frequently asked questions we get from customers calling in about their home’s heating systems. Yours might be here too!

I thought I smelled something burning when I first turned my heater on. Should I be worried?

It’s relatively normal to smell a burning odor when your first turn on your heater after it hasn’t been used for a long time. Heaters collect a lot of dust, so what you’re smelling is all that dust burning off as the equipment heats up. Dust buildup can weaken your heater’s performance, cause ignition delay issues, and even lead to significant part failures down the line. If you’re smelling dust burning off, it’s a good indicator that your heating system needs some preventative maintenance.

When my heater starts up, it makes a boom or popping noise. Does it need a repair?

If your heater makes a boom or popping sound when starting up, something is preventing the gas from igniting right away. Subsequently, the gas has a chance to build up inside your heating equipment, and when it eventually ignites, it explodes. Granted, the explosion is small, but over time, these booms can damage your furnace.

The most likely culprits behind this problem are dirty burners getting in the way of instant ignition. If you don’t know how to clean your furnace’s burners correctly, an HVAC technician can clean them for you. They’ll also provide your heating system with a thorough inspection to ensure that there isn’t a different underlying problem.

The furnace’s flame looks a bit yellow and orange. Is that bad?

Unfortunately, yes. If the flame is yellow, orange, or red, the flame isn’t getting enough oxygen. When the flame in your furnace doesn’t get enough oxygen, it doesn’t burn as hot or efficiently. This also means that the combustion process will produce more carbon monoxide (CO) than it otherwise would.

A furnace’s flame should burn bright blue. If the tip of the flame is yellow, that is also fine. Yellow and orange flames are a problem typically caused by dirty burners, so again, if you don’t know how to safely clean them yourself, enlist the help of an HVAC professional.

The pilot light keeps going out. Is my heater broken?

Your furnace will need either a repair or some maintenance, but it’s extremely unlikely that you’ll need a system replacement, so don’t worry! Usually, a pilot light won’t stay lit because of some kind of issue with your furnace’s thermocouple. The thermocouple is a safety device. If it doesn’t detect a flame, it cuts off the gas supply coming into your furnace to prevent a dangerous buildup.

If the thermocouple has accumulated a layer of dust or grime, it will have trouble sensing the pilot light flame, so it will shut off the gas, and the light will go out. The thermocouple can also have trouble if it breaks or deforms due to old age.

My heater is making a humming sound that seems louder than usual. Is that normal for an older system?

Humming can occur for numerous reasons, including:

• Loose, vibrating equipment
• Not enough lubrication in the blower motor
• A failing blower motor
• A damaged capacitor

While some furnaces run more quietly than others, if you hear a humming or buzzing sound you don’t recognize, it’s best to get your system checked out by a professional. This can prevent a minor problem from becoming a significant and much more expensive one if you catch it early enough.

For reliable heater and furnace repair in Centreville, don’t hesitate to contact Service Specialties: (703) 968-0606.