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  • Writer's picturemike marcinkiewicz

How to tell if Furnace Heat Exchanger is Cracked

How can you tell if your furnace heat exchanger is cracked? That's a question asked by many homeowners of Orangeville, Shelburne, and the rest of Dufferin County. It's especially concerning if your furnace just stopped working and you are waiting for the repair technician to arrive to your home. Firstly, what is so important about a heat exchanger anyways? Well, it's the main component of the furnace that allows the heat energy produced by natural gas or propane to be transferred into your home's indoor air. Essentially, the heat produced by fuel is transferred by air passing over the coils through a process know as conduction. Because your indoor air never comes in direct contact with the burning fuel, it allows the furnace to exchange the heat without bringing the products of combustion into your home. Hence, the heat is exchanged into your house without any poisonous combustion gases. Advise to Homeowners A homeowner will find out quickly that their furnace heat exchanger is cracked if they smell a strong, strange, and smelly gas scent coming out of their furnace vent outside. If you smell it, immediate call for furnace service in your area! Heat exchanges fail due to mechanical expansion and contraction of the metal which leads to wear and tear and eventually cracks. This is usually caused by two main reasons, firstly the furnace is not getting enough air and secondly that the furnace is over sized for the home. When a furnace doesn't get enough air due to blocked registers or a dirty filter it over heats and stresses the heat exchanger metal. Additionally, restricted combustion air to the furnace and slow condensation drainage will lead to incomplete combustion that soot and clogs heat exchangers. An over sized furnace will 'short cycle' and and cause constant metal expansion and contraction and without doubt not last many years. Furnace Repair Technician Once your repair technician arrives to diagnose your furnace service they will use a combustion analyzer to perform a test for carbon monoxide. A high reading will indicted that your heat exchanger is failing or has failed. A furnace technician will also look for signs of a flame roll-out, control board codes, and other signs of a failed heat exchanger. Once confirmed, the technician will do a visual check of the exchanger to find the cracks. At that point, the technician will present two solutions for you.

  1. Replace heat exchanger

  2. Replace with new properly sized furnace

A failed furnace heat exchanger is a serious matter as carbon monoxide and other products of combustion are entering your indoor air. It can harm you and your family so please choose a reputable and reliable heating contractor such as EMI Air Systems to perform your furnace repair. Call Mike - 437-343-0275 email- web -

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