Cracked heat exchanger and unsecured vent piping leads to high CO levels in home

High levels of carbon monoxide (CO) in a home sent one person to a hospital for CO exposure.

A gas utility company was contacted and a technician attending the site registered a CO reading of 500 ppm at the front door. After safely airing the home out to eliminate any existing  carbon monoxide, the technician cycled the furnace and through the use of his CO detection device found that carbon monoxide was entering the space from a faulty vent connection of the concentric vent kit before it exited the side wall of the dwelling. 

The equipment involved a gas fired furnace in a basement, providing heat for the two storey residential home. During a furnace heating cycle, the products of combustion created by the gas burners pass through a heat exchanger and enter the venting system to exit to the outdoors. The furnace was red tagged and taken out of service.

A contractor, hired to look at the furnace, found that the heat exchanger had a hole in it and the vent piping was not glued securely to the concentric vent kit. 

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