I often abbreviate the term for heating, venting and air conditioning down to HVAC. But it appears that most people think only of the heating or the air conditioning portions of the term and ignore the venting portion. And that is the most important part of an HVAC technician’s job.
An improperly vented fossil fuel-burning appliance can be deadly. The byproducts of combustion are carbon monoxide (CO) and other unpleasant gases and moisture. CO is colorless, odorless and tasteless, but when the concentration of CO is greater than 100 parts per million, the CO becomes toxic by combining with the body’s hemoglobin to form carboxyhemoglobin in the blood, preventing the hemoglobin from releasing oxygen to the body’s tissues.
People exposed to low levels of CO poisoning may suffer headaches and dizziness similar to the flu, but when the flulike symptoms continue, it is very important to seek the advice of a doctor or other medical professional. Extended low-level exposure can be toxic to the heart, the nervous system and other vital organs. Exposure to high levels of CO is deadly.
Everyone should have at least one CO detector in each bedroom and others near fuel-burning appliances. When in doubt about where to place a CO detector, seek help from your fire department or health officials.
If a range hood is nonventing or is a recirculating type unit, any experienced technician can install it. It’s when the hood is designed to vent to the exterior that I find problems. Either the venting pipe ends in an attic or the hood vents into a wall cavity. A vented range hood must vent to the exterior all the way through the roof or through a sidewall.
Over time as the fan is used, grease will be pulled into the flue or cavity where it will accumulate, ready to fuel the first accidental range-top fire, and it will blow like a torch through the wood structure of the home.
Also check the vent pipes from gas and electric dryers. The pipe must be a smooth-walled metal pipe where possible and vented to the exterior. Lint is highly flammable, and experts estimate it to be responsible for more than 100 injuries a year, resulting in at least five deaths and causing more than $35 million in damages.