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Serving West Michigan Since 2004

Serving West Michigan Since 2004

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Common Venting Issues in High-Efficiency Furnaces

If your furnace is having some issues, the first thing you might do is lurk around on the internet a bit in search of some helpful advice (that’s why you’re reading this blog post, right?).

However, it’s important to understand which kind of furnace you have. After all, a high-efficiency furnace is going to work a bit differently than your conventional furnace, so you can expect it to have some unique issues, especially in regards to its ventilation. In this post, we’ll go over how the two systems are different and which problems are unique for high-efficiency furnaces.

Of course, if you find yourself overwhelmed, don’t hesitate to call up an expert of furnace repair in Grand Rapids, MI to come check out the furnace right away.

The Main Difference Between High-Efficiency and Conventional Furnaces

It all has to do with ventilation. Both furnaces create byproducts that needed to be vented outside of the home, but the means by which they do it is different.

For a conventional furnace, it’s going to create carbon monoxide and other poisonous exhaust that must be vented out into the atmosphere as a gas. This is going to appear as a large metal exhaust vent.

For a high-efficiency furnace, however, it’s capable of taking those byproducts and using them to create even more heat. But the resultant byproduct is an acidic mixture of water and carbon dioxide. In order to facilitate this process, high-efficiency furnaces will use two PVC pipes sticking out of your roof or the side of your home: one for the intake, and one for the exhaust.

Common Venting Issues in High-Efficiency Furnaces

Other than the venting, both furnaces operate similarly and will have similar repair issues. That leaves for some unique issues that exist in a high-efficiency furnace.

Obstructions in the Air Intake Vent

The furnace requires a steady stream of oxygen to fuel the combustion process. If that airflow is blocked or restricted, you can expect combustion problems. In some cases, it can get bad enough that flames from the gas burners will “roll out” to find more oxygen.

Common causes for obstructions can include:

  • Clogged, dirty air filters.
  • Birds nests or leaves in the air intake vent.
  • Obstructions in the air supply pipe.

Exhaust Gasses Recirculating Back Into the Intake

If the air intake and exhaust pipes are installed too close to each other, it can prevent them from doing their jobs properly. The result is exhaust gas being sucked into the air intake vent (which is only supposed to receive clean air!). Without enough pure oxygen in the mix, your furnace will have issues with combustion.

Condensate Line Clogs or Flooding

Part of the exhaust process of a high-efficiency furnace is to release condensation. It does this through a drain line and, as backup, a condensate drain pan. If the drain line becomes clogged by debris, the condensate will fill up the pan until it activates a pressure switch. This switch will then shut off the furnace until the pan is emptied.

However, if the pressure switch fails, it can result in the condensate pan spilling over. This can be an absolute disaster in the event that your furnace is installed in the attic.

Does your furnace need service? Contact Westshore Mechanical today to schedule service. Serving West Michigan Since 2004

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