Notice
May 06, 2020

Why Can't I Put an Elbow Directly into the Top of NPE Tankless Water Heaters

Why no elbow direct into npe tankless water heaters main image.jpg

We strongly recommend installation by trained and professional contractors only. Professional technical assistance is required to execute any procedure on Navien units.
Find a plumbing expert by clicking here.

 

When venting Navien NPE tankless water heaters, it is important that you do not start the vent run with a street elbow at the vent collar. The Navien NPE tankless water heater installation and operation manual requires the exhaust pipe to be inserted into the collar 1-3/4", or the pipe does not extend far enough past the internal gasket and make contact with bottom of exhaust collar to seal and secure exhaust venting properly.

exhaust pipe into Navien NPE tankless water heaters

PVC fittings are generally manufactured with a hub, or female connection, on each end (figure 1). The pipe inserts into the hub and is glued in place.

Because of the radius of the elbow beginning just above the fitting end (male end) it will not allow the elbow to insert far enough into the collar of the unit to seal by the gasket.

elbow into NPE tankless water heaters warning

Ensure that the vent pipe is properly beveled prior to installation and that the pipe is fully connected to the exhaust gas vent fitting. Failure to properly bevel and install the pipe can lead to gasket failure and flue gas leakage, which may result in serious injury or death.

We strongly recommend installation by trained and professional contractors only. Professional technical assistance is required to execute any procedure on Navien units.

Find a plumbing expert by clicking here.