Heat exchanger cracks

Heat exchanger racks come in many forms but are all very bad.  A heat exchanger is a metal container that your furnace gas burns in to exchange heat into your home.  These gases create carbon monoxide (CO).  Carbon monoxide is a poisonous gas that can kill you.  These cracks form over years of operation due to expanding and contracting of the metal.  Cracks can be small or large and can even become large holes or splits.

Shown is a common crack on an 80% furnace and was reading 45 ppm CO at the time it was removed.

Cracked heat exchanger repairs?

Heat exchangers cannot be repaired.  They cannot me welded or sealed, if your heat exchanger is cracked you either need a new heat exchanger or a furnace replacement.  To determine which is right for your furnace keep these things in mind.  How old is your furnace?  Most furnaces will have a 20 year warranty on the heat exchanger itself.  What condition is your furnace in?  Many units even after 20 years are still in good enough condition to have a replacement be a viable fix.

Cracked heat exchanger cost?

The cost will vary largely based on age, style and warranty status.  An average heat exchanger under warranty would cost around $800 installed whereas one not under warranty can cause anywhere from $800 to $3000.  It is always best to get several opinions on the crack, the cost and the warranty status.  We have found that many companies neglect to mention the warranty status. In EVERY case however it is unsafe to run your furnace is it has a crack in it. The dangers of CO poisoning are very serious, and kill without warning.