I don’t need a chimney sweep because I don’t use my fireplace or my chimney. Well, I’m sorry to be the one to inform you; that’s WRONG! It is most probable that you use your chimney, and there are many reasons that even if you genuinely don’t, you should get it inspected. That’s right, even if you don’t use the actual fireplace itself or a stove connected to it, it’s more than likely the chimney or lack thereof is aiding in your home.

So what is using my chimney?!

The house, in most basic terms, is the utilizer of the chimney. This time we aren’t talking about aesthetics of land value. No, there is a specific group of objects that use a chimney beside the fireplace. Gas-fueled heaters, from boilers to water heaters, and furnaces to room heaters, if it generates heat from the Earth’s air, then it’s a gas heater.

Of course, you may have electric heaters, but gas is all the rage. It’s cleaner for the environment, uses inexpensive fuel, and only increases its heating efficiency. If you aren’t using gas and have a pipeline nearby, it’s a good idea to make the switch. But if you make the switch, know to get the chimney checked annually.

Water and animals also are worries for the chimney, water causing many problems with its presence—Rust, deformation, and sometimes causing a chimney to cave in on itself and the home. Water is no joke; it’s architecture’s arch-nemesis for a reason. If you live in a stormy area, it can only do good to get checked for damage from the dastardly H2O.

Then animals are less of a threat. But still one, they are a case by case thing. If you hear animals in the chimney, it can only be good to have them humanely removed for their help and our own.

Why do the gas-fueled devices use my chimney?

Gas needs to go somewhere. Some gas heating appliances have their vents built or through the house, especially when made with one in mind. However, many release their exhaust into the home without a care in the world. Thankfully this gas is safe to breathe, as long as it doesn’t stagnate and build up in the house. The way for the gas out of the house happens to be the chimney.

What’s the problem, and how should it be dealt with?

One of the problems is relatively simple; the gas is acidic. Now it’s not so acidic that it will melt the chimney completely, but it will eat away at the chimney lining and eventually the bricks, which lets in water and can cause irrecoverable damage.

The only way to handle this situation is to have an inspection between the chimney and the appliances. Some sources say one flue per gas appliance, while others say lower efficiency appliances may share a flue. However, it is vital for devices of 80%-90% efficiency with chimneys or older models to have things looked over; or if there are drastic age differences between the appliance and the chimney itself. Even when neither of these applies, it is recommended to have the inspection anyway for your safety.

They need to match for a few reasons; the following problem is heat. Heat is a crucial part of creating drafts. Many may use smaller chimneys to prevent heat from escaping, but some of that heat needs to escape to maintain proper airflow. However, there is less excess heat in higher efficiency machines, so a higher proportion of it is required in order to create a draft.

To be more precise on the importance of this note, acids are not only dangerous for the flue of the chimney but also the gas-fueled machine. The device must take in gas from the air, and whatever is in that air is ran through it. So any cleaning products, local pollution, etc., already runs through the system. When chlorides like the aforementioned meet water, hydrochloric acid is born, and moisture with other pollutants or even the residues in the flue is likely to make more acids.

Meaning the next problem is the fact that combustion creates water vapor. You don’t just have the bottles and rain to worry about; it feeds into itself. The only way to prevent these unwanted mixes is to have the water vapor vented out before it becomes liquid, which means fast and while still warm, as water likes to condensate. So the key to one of the issues comes back around to a home’s natural enemy, water.

The last problem is that a draft is also needed to get oxygen, a key ingredient in combustion and the source of heat for these devices. In a 10:1 ratio, the former being the required cubic feet of oxygen for the single cubic foot of natural gas. If not enough oxygen is present, instead of the relatively safe and inert CO2 or Carbon Dioxide, CO, aka Carbon Monoxide, is released into the air. A toxic gas, which most homes come equipped with detectors specifically for.

As it turns out, just having the two-match prevents a whole bevy of problems. The ventilation helps get the acidic gas, prevents the released water vapor from mixing with other air pollutants or liquifying in the chimney, and provides oxygen to avoid toxic gasses filling the home. I think that’s enough to justify getting a chimney inspection just once a year; any slight imbalance, after all, can lead to dire circumstances.