Cracked Heat Exchanger Replacement on Furnaces
The heat exchanger plays an extremely critical role in a furnace. It safely transfers heat generated from the flame to the circulating air in the home. The burning fuel heats up the heat exchanger which in turn warms the air in your home as it passes through the furnace. This is a continuous process as the furnace runs in heating mode during winter.
What are the dangers of a cracked heat exchanger?
When natural gas or propane burn, they produce fumes containing carbon monoxide, carbon dioxide, water vapor and soot. A furnace depends on the heat exchanger to safely channel these dangerous fumes to the chimney while transferring the valuable heat into the home. If the heat exchanger is compromised by a crack or any type of breach, flue gases and carbon monoxide will leak into the home resulting in illness and possibly death of the occupants.
What is the cause of heat exchanger cracks?
Most premature heat exchanger cracks are caused by furnace overheating resulting from restricted airflow. The heat exchanger then overheats causing thermal fatigue of the metal. Over time, the heat stress causes cracks to develop near weak areas such as bends, seams or welds. The most common cause of restricted air flow is simply a dirty air filter.
An over-sized furnace can also cause overheating and resulting heat exchanger cracks. Too big a furnace with too little duct work or too little house will result in less airflow causing overheating and heat exchanger cracks.
Leaking water from an improperly installed/maintained AC will cause heat exchanger rust resulting in a breach. In most cases, a crack will disrupt the flame and/or set off a carbon monoxide detector in the home.
If a technician has condemned (red tagged) your furnace due to a cracked heat exchanger, you may be faced with two choices. Replace the heat exchanger or replace the furnace. In either case we can help you. If your budget allows you and the cracked heat exchanger in NOT under warranty, your best option is to replace the furnace. If the heat exchanger is still under warranty and the furnace is still in good shape, you may want to have the heat exchanger replaced. Especially if your budget does not allow a new furnace. Give us a call to help you make the right choice. You are free to shop around. You do not have to let the company that condemned your heat exchanger pressure you to let them do the job.
Here are two primary heat exchangers we replaced recently showing the cracks. We typically replace both primary and secondary heat exchangers