Common Problems with Gas Appliances & Older Chimneys

Gas heating appliances continue to grow in popularity for many good reasons, not the least of which is savings on utility bills for the homeowner. Gas is a clean-burning fuel that is safe and convenient to use. From fireplaces and stoves to furnaces and hot water heaters, gas is the preferred heating fuel for many people.

gas appliecesProfessional installation of a new gas appliance means many years of heating comfort within your home. A challenge arises, however, when you elect to vent your new appliance through an old existing masonry chimney. This is a good option for some homes, but specific protocols must be followed to ensure that the hookup allows the appliance and chimney to operate safely.

Problems that can arise with an improper installation of a gas appliance to an existing chimney include drafting and venting issues as well as the accumulation of excess condensation and acids within the flue.

Drafting and venting issues

When working optimally, a vent system will pull toxins from burning gas up and out of your home. If the chimney you’re using to vent the appliance doesn’t have the correct size flue, drafting can be impaired.

Modern gas appliances such as fireplaces and stoves are highly efficient, sending the majority of the heat they produce into the home rather than up through the vent system. Because less heat rises in the chimney, the upper areas of the chimney will remain colder, which hampers the draft. When this happens, the only place for fumes and toxins to go is back down into the home.

Your existing chimney was designed to vent wood smoke from a specific-sized firebox, so certain adjustments by a certified chimney specialist may be required during the installation of a new gas unit. Ensuring optimal venting is a key reason to have your gas appliance professionally installed rather than attempting to do it yourself.

Condensation and acids within the flue

If your gas appliance’s connector pipe is too small for the existing flue, acids and other dangerous chemicals can collect in the flue during combustion. Hydrochloric acid can be produced when chlorides and other acids in the air combine with moisture from condensation. This toxic environment can erode your chimney liner and sections of masonry within the flue, leading to extensive and costly damage.

gas fireplaces

Additionally, if the chimney isn’t providing adequate drafting, these poisonous chemicals – including deadly carbon monoxide – can enter your home. Unfortunately, there’s no way to prevent some condensation when the gas appliance is in use, so it’s very important to have the appliance installed by a certified professional and then inspected on a yearly basis.

Signs of chimney damage

Chimney damage from improper venting often leaves signs that you can spot including:

·    Deterioration of the bricks or mortar of the chimney

·    Discolored chimney masonry

·    Peeling wallpaper in the area of the appliance/chimney

·    Stains on the ceiling

·    Damp or wet sections of interior or exterior walls of the home

·    Bubbles or blisters within the paint on walls

If you’ve had a gas appliance connected to an older chimney and notice any of these signs of chimney damage, it’s wise to arrange for a professional inspection of the chimney and the appliance before using it again.

Fluesbrothers Chimney Service of Kansas City, KS, is ready to help with all inspection, service and repair needs for your gas appliance and chimney. We also will install your new gas unit and make sure it’s done right the first time. Call (913) 236-7141 with questions or to schedule an appointment.