Hello,

I have a 11 year gmpn100-4 which stops working after 5 minutes of running. Called a technician and he is suggested that the heat exchanger is cracked. He also showed me flames coming out of the combustion chamber which he says indication of cracked heat exchanger.

Question, should I replace the unit or just have it fixed.

Thanks,
Ttusond

At 11 years of age if the heat exchanger is defective I would replace the unit. It will cost more to repair than what it is worth.

Chaeck to see if there is a warranty on the heat exchanger. Sometimes it's lifetime, but then again there is the labor to install it.

Thanks for prompt response, I spoke with Goodman and the heat exchanger is still under warranty. The cost to replace HE would be around $900 and the cost to replace new goodman furnace would be around $1800 , both including labor. As per my research, older goodman furance had problems but recent once, year 200 and above are same quality as other branded furnace. I am correct, I am inclining to get a new goodman furance.

As I mentioned before get the new furnace. Goodman had problems with the series furnace you have now. Many heat exchangers failed and burners went bad, seal rings popped etc. While you might save some $$ now all the other parts of the furnace are 11 years old and they will also be prone to fail because of age. I agree with your decission to buy a new furnace.