Your New Tankless Water Heater: Key Venting Requirements

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If you are thinking of installing a tankless water heater, or if you have recently purchased one, it is important that you pay close attention to venting. A unit that is not properly vented can cause your water heater to fail and, even worse, it can be quite dangerous.

The location of the water heater is important. There are advantages to installing it inside the home, close to the kitchen or bathroom. Because they don’t take up much room, you can have one just about anywhere. Installing it outdoors eliminates the risk of carbon monoxide poisoning, but if properly vented, there is no reason not to have it indoors.

Tankless water heater venting is something that should be handled by an HVAC professional, to be sure it is done properly, with the right materials. Some things to keep in mind:

  • Make sure that you are using the correct piping material. Most require Category-3 piping.
  • Keep the venting run as short as you can. It is more efficient, and will lengthen the life of your system. Check the manufacturers instructions and do not exceed the maximum length.
  • Do not tie your tankless water heater venting into any other venting. This is very important. In most cases, you can’t tie your venting into any other venting, such as a stovepipe or a chimney. If you do, you must use the category-3 piping within the chimney, stovepipe or other venting.
  • Horizontal venting should slope away from the tank, so that condensation does not run into the unit and damage the heat exchange. If you cannot do that, or if your venting is vertical, you must install a condensate drain within three inches of the vent connection.

When in doubt, consult a professional. Proper tankless water heater venting will extend the life of your unit and is safer. Tankless water heaters are a good investment that will last a long time if properly installed and maintained.

Residents of the Cincinnati area can call Apollo Home Heating, Cooling and Plumbing with questions about tankless water heater venting, installation and repair.

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