We worry often enough about the air conditioner because staying cool in the summers is a top priority, but so is staying warm in winters. Yet, many of us take the furnace noises for granted and ignore them. Like the AC, the furnace sounds are also signs of impending troubles.
Instead of talking about all probable sounds the furnace might make, we shall concentrate on just one, which is the hissing sound. If you have a hissing furnace, this article will help you understand the cause behind it as well as what you should do next.
What Does The Hissing Sound Mean?
A hissing furnace suggests there is some airflow-related problem. It can be something as minor as a clogged air filter or something as major as a cracked heat exchanger. In some unlikely cases, it may also be a combination of problems. Nevertheless, more often than not, they all relate to issues that have to do with faulty airflow.
Probable Causes Of A Hissing Furnace
1. Clogged Air Filter – Homeowners should regularly replace the dirty air filters with clean ones. Nonetheless, that happens rarely. We get so busy dealing with other important things that minor issues like the dirty air filters get relegated to the backbench, where they lie forgotten. The dirt keeps accumulating on the filters until the free movement of air becomes impossible. When that happens, air forces its way through several layers of dust, dirt, and debris, creating that hissing sound.
What To Do – Thankfully, this is not a huge problem. It’s one of those which the homeowners themselves can handle. All you need to do is check the specifications of the current air filters and replace them with new ones having the same specs. Typically, they are either clip-on or sliding type, so the task can be completed with ease.
2. Leaking Air Ducts – The furnace delivers hot air indoors via a network of ducts. Any tear or leak in the ducts gives the air a means to escape. The hissing sound is generated when a large volume of air tries to escape from a relatively small opening. Often the cause of leaking ducts are:
1. Age-related duct material degradation.
2. Tears that are caused by a pressure difference.
3. Tears caused due to mishandling of ducts.
4. Critters eating through the duct material, etc.
It is essential to keep an eye on the condition of the ducts. How can you do that considering the ducts lie beyond the walls of the house? The best way of doing that is through an annual ductwork inspection. Any trained HVAC professional can do the inspection provided they have the necessary equipment to measure the air pressure.
What To Do – Whether you are dealing with leaky ductwork or not isn’t something a homeowner can decide on their own. Only a professional who deals with such things can help you. Consequently, call your HVAC technician to inspect the ductwork. If he finds any tears, holes, or gaps, he will proceed by patching them up. This may involve sealing the openings using industrial adhesives or replacing a section of the ductwork.
3. Cracked Heat Exchanger – A cracked heat exchanger is a dangerous situation. It is because when the heat exchanger is cracked, it allows the combustion gasses to escape, which are hazardous to human health. The escaped gas can also ignite and result in a fire. SO your property is also at equal risk. In the case of a cracked heat exchanger, the hissing sound is heard when the gas escapes the combustion chamber. Thankfully, there is one another give of this occurrence, and that is the foul smell of gas. So when you hear the hissing sound, and smell a gas leak, it signifies your heat exchanger is compromised.
What To Do – The first thing to do is to shut down the power supply and the gas supply. Next, immediately vacate the house, move to a safe distance, and immediately call for emergency help. Do not linger indoors after turning off the gas and power supply because inhaling the gas can make you feel dizzy and nauseous.
4. Dirt Buildup On Heating Elements – A lesser-known reason for a hissing furnace is dirt buildup on the heating elements. If you are wondering how dirt could get inside the furnace, don’t be. Dirt can get in anywhere through the smallest of openings. That is why HVAC contractors recommend annual maintenance of the furnace because it takes care of the furnace cleaning as well. Dust and dirt collected on the heating element of the electric furnace create a hissing sound when it heats up. However, this sound is accompanied by the smell of burning dust, so it is easy to recognize. Moreover, once the accumulations have burned up, the sound and smell both disappear. This usually goes away within a few minutes to an hour.
What To Do – Typically, you should wait at least for an hour for the sound and smell to go away on their own. If either persists, switch off the furnace and call an HVAC technician because it means dust is no longer the culprit and the problem lies elsewhere.
Maintenance Is Critical To Resolving Hissing Furnace Sounds And Others
All your furnace wants from you is a little care. Annual preventive maintenance ensures your furnace stays in tip-top shape and proper working order. When your furnace is well maintained, no noise from it will ever invade your living space. Besides changing the air filters every month, schedule the furnace service or tune-up right before switching on the heating for the first time in the season, and you will be all set to enjoy the warmth and coziness of your dwelling.
If you are plagued with a furnace that makes loud random noises, do not hesitate to call a technician immediately. The noise is a way of telling there is a problem that needs to be taken care of.
To schedule the maintenance of your HVAC, call Aztil Air Conditioning. We are a premier HVAC contractor in South Florida, offering world-class services at pocket-friendly rates. To book an appointment, call +1-888-729-8452 anytime.