The heat exchanger is a metal component that transfers burnt gases through to the flue.
If there are cracks in the heat exchanger, flue gasses containing carbon monoxide can escape and be pushed into the property by the appliance's internal fan or ductwork.
Will every crack 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.
A hairline crack may not leak during our initial on-site inspection of 45-60 minutes. However, if the unit is run for longer, these cracks will expand as the temperature of the metal increases.
How does a heat exchanger work?