The main heat exchanger is the primary heat exchanger and the condensing heat exchanger is called the secondary.
Faulty furnace secondary heat exchanger.
Replace the heat exchanger or replace the furnace.
Carbon monoxide is a byproduct of the combustion process and it can seep through the cracks of a damaged heat exchanger.
This is not always the case.
When we talk about heat exchangers failing often times technicians and homeowners only think of the cracked heat exchanger.
If you smell a formaldehyde like odor you should immediately call a professional for a furnace inspection.
How these failures occur usually depends on the circumstances mentioned below.
All forced air condensing gas furnaces use two heat exchangers.
The life of a heat exchanger is not by any means easy.
If the heat exchanger is under warranty this option is a good way to go unless it is unavailable in the time frame needed which can be immediate in cold weather.
There are only two options if a heat exchanger is bad.
Heat exchangers are also vulnerable to rust and corrosion.
Normal wear and tear.
Anatomy of heat exchanger failure.
Although you should certainly not wait until your carbon monoxide detector sounds to determine if your heat exchanger is broken if you do get an alarm it is a strong sign that damage is present.
Most heat exchanger failures involve stress cracks forming near bends welds and other thin weak areas.
The chamber becomes corroded from the inside possibly due to a reaction from acidic condensation on the polypropylene coating.