How to Vent a Tankless Water Heater

How to Vent a Tankless Water Heater

Should you conclude that a gas tankless water heater is the best option for your application, one thing to address is the venting. Proper installation of venting is going to count a lot for the efficient performance of your tankless water heater and its durability.

What are the main aspects of venting?

The venting for your tankless water heater includes several components, and you should learn a thing or two about each of them before installing the venting:

  • Vent adaptor and exhaust (made of stainless steel)

You need the vent adapter for connecting the tankless unit to the exhaust hose. You may go with a 3in adapter or 4in type, according to the tankless water heater you’re about to mount.

The vent pipes have to be made of stainless steel and approved by UL, and piping made of PVC isn’t a good option.

  • Outdoor installation

When you feel like installing venting for your indoor unit is too much of a hassle, you can always go with an outdoor unit. Look for the models that are designed for outdoor installation and don’t require venting.

Which are the options for venting a tankless water heater?

You must vent the tankless water heater according to the manufacturer’s instruction. Proper venting will ensure the effective operation of your tankless water heater and also reduce the risk for danger and carbon monoxide poisoning.

Tankless water heaters require horizontal or vertical venting, which some people know it as water heater venting through the roof.

  • Horizontal installation

There are actually two ways in which you can install the venting horizontally, and here’s the main one:

  • You can use a downward slope where you plan to install the adapter for the vent, a ninety-degree elbow, along with the vent hose made of stainless steel. The tube should have the right length, and you need to maintain the exhaust outside the sidewall of the home. Use a small metal or plastic cap for connecting the inside of the vent along the outside. A 90-degree elbow is necessary for completing the installation.

In the case of vertical installation, with an upward slope, you only have to add vertical condensation trap into the elements.

  • Vertical installation

Vertical installation is a lot more versatile than horizontal installation since it includes several aspects to consider. However, the elements that may be needed for the plant can remain the same. You have to buy an adapter for the vent, a 90-degree elbow (at least), and a condensation trap.

For some manufacturers, you can go without the condensation trap, whereas others come with built-in condensation traps. Add the stainless steel on your shopping list as you need it for discharging pipe to escape the outside of your residence. A fire stop for each ceiling where the water heater is ventilated through is required, as well. Don’t forget to get a storm collar, a rain cap, or a 90degree elbow for ending the attachment and a roof flashing.

What about the combustion air?

Combustion air is necessary for tankless water heaters, and you have to know that way to provide combustion air to the unit. Once you install it in an open space, combustion air isn’t going to bring any air inside the household.

Some tankless water heaters can perform in various atmospheres where they don’t collect fresh air outside the exterior area of the installation.

The rule of thumb is that any tankless water heater that uses combustion air has to have at least 10,000 cu.ft. Around the unit. Enclosed areas (closets, for instance) require air ducts and extra air inlets. The models needing combustion air from the outside should also come with a second hose that has to be put in. It will clean air from the exterior of your home into the environment where the unit is mounted.

What are the common choices for venting a tankless water heater?

Venting the tankless water heater isn’t an easy job, and you should look over the options for selecting the best scenario for your application.

  • Fan assisted non-direct vent outdoor

It’s a solid choice for both horizontal and vertical venting. It includes an electric fan that pushes the gas outside the space, pulling oxygen required for combustion from inside the area.

  • Fan assisted sealed combustion direct vent indoor

It allows both vertical and horizontal venting. Combustion air gets to the gas burner right from the outside.

The water heater includes a sealed cover and doesn’t use air from the area of installation. You fit in two pipes (one concentrical running from the water heater through the wall/roof), one being for exhaust and one for the fresh air intake.

  • Outdoor

The outdoor tankless water heater gets combustion air right from the atmosphere around it, expelling exhaust by a consistent method. It’s a reliable choice for warm regions.

Some tips for venting instead of a conclusion

Venting a tankless water heater isn’t simple, so several tips aren’t going to hurt:

  • Outdoor tankless water heaters let you free indoor area, clearing the space inside the home and not needing further emission
  • Indoor tankless water heaters collect air from the outside. They are ventilated with a direct vent or power vent. Direct-vent units collect air from the house, whereas power-vent models only use an exhaust vent. They require a larger area for installation so that they get enough air for combustion.
  • Condensation tankless water heater reduces the costs of installation. the exhaust vent is made of plastic or PVC, which can only cut down the spending
  • Pipe covers and interesting termination points stand out as attractive emission solutions
  • Recess boxes let the tankless water heaters adjust within walls so that they don’t hang from the home exteriors. The setup allows the water heaters to fit inside the home’s frame, without suspending from aside.
  • Tankless water heaters with coaxial vent style present several safety benefits. Should any of the pipes start leaking, the air will remain within the coaxial vent, without entering the residence. Read more about it.
  • Tankless water heater venting styles lets you try various emission options. They can blow exhaust from the unit horizontally using the fans and allowing vents to terminate on multiple positions of your household.
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