Should You Replace Your Furnace If You Have A Cracked Heat Exchanger?

We received a call for a clean and check inspection when we discovered a cracked heat exchanger in a forced air furnace. We verified that the heat exchanger was cracked by removing the plenum (top duct work on the furnace) and the air conditioner evaporator coil.  The crack in the heat exchanger has the potential to leak carbon monoxide into your home.  Some articles on Google mention that a crack in the heat exchanger is not a significant problem, this is simply not true.  

The heat exchanger separates the air stream entering the home from the exhaust gases in the furnace.  A crack is a compromised system and this must be addressed before allowing the homeowner to continue using the furnace to heat the home.  Carbon Monoxide poisoning in the worst cases has proven deadly, and while this is the worst case, we can't rule out the possibility.   

Cracked Heat Exchanger

This furnace ended up being replaced due to the age and the cracked heat exchanger.  Sometimes customers choose to replace the heat exchanger verses replacing the furnace.  This is a decision that the homeowner has to make based on cost and the age of the system.  Replacing a cracked heat exchanger is like doing open heart surgery on a furnace, and just because you have a new heat exchanger does not mean that the rest of the components are new.  Most furnaces that have cracked heat exchangers are older models 12-20 years old and the homeowners should consider replacement due to the age, as well as the general condition of the furnace.  

Some manufacturers have a 10-20 lifetime heat exchanger warranty.  This warranty is for parts only and doesn't include the labor in most cases.  The average heat exchanger replacement takes one technician 4-5 hours.  If a customer is told that they have a cracked heat exchanger by another company, CMR Mechanical requests that one of our technicians verify the findings before we offer any recommendations.  This is to ensure that the heat exchanger is in fact cracked, and that the diagnosis by another company is correct.  Only then can we move forward with verified information on the furnace.   

CMR Mechanical technicians do a thorough inspection of the furnace any time we are on a service call, on a clean and check, and when we replace the evaporator coil on the furnace.  CMR mechanical prides itself on honest, quality service. Call us today at (734) 424-9555 to receive a thorough inspection of your furnace!