Navien 30009933A O-Ring Kit

Like the fact I didn't need to create a list and then shop individually for these seals. The heaters will leak sooner of later, best to have these on hand .

Your Navien should come with a bag of these o-rings taped to the right hand side of your tankless but if gone buy this set. Has all the O-Rings you need for maintenance.

This is the exact kit I needed to replace several old orings for my tankless water heater. I gave a 4 and not 5 star simply because the labelling doesn't match the part numbers in manual and could have used a few more of each size, but definitely worth it. Fixed up drip leaks I had perfectly

There were at least 5-6 different metric sizes or all of the various o-ring requirements inside the unit.

Ordered this kit for my Navien NP-240a. Not enough o rings to do the job and a few that didn't fit. Luckily I had an Oring kit from Princess auto that had what I needed to finish the job. Wouldn't bother buying again.