The heat exchanger is an important component of every gas heating appliance. The heat exchanger is a metal component that is generally a set of tubes or coils which stores the combustible material from the burners.
If a gas appliance has a cracked or damaged heat exchanger there is a possibility that combustive materials (carbon monoxide) will escape through these cracks and openings. It will then be pushed into the property via the internal fan of the appliance. Once the combustive material has made its way into the fan of the appliance it will then be blown into the property through the ductwork and then out of the heating registers.
Eventually, every crack will produce carbon monoxide. Depending on how big the crack is or how long the appliance has been running will determine if carbon monoxide will be produced into your property. A hairline crack may not leak during our initial on-site inspection, however, our inspection are anywhere from 45-60 minutes so as the unit is used for longer periods of time these cracks will increase and expand as the temperature of the heat exchanger is increased. A hairline crack can produce carbon monoxide into the property and should be addressed right away to minimize your liability. Basic science- Heat causes metals to expand.
For more information regarding testing for negative pressure & carbon monoxide spillage please click here