Replacing our hot water heater with a tankless sealant question

[Chronobomb]

Hello,

After 4 years of full timing, our hot water heater has developed too many leaks. The new one is somewhere between the outside plate and the water heater so I’m officially done with it.

Replacing the tank looks very straight forward. My question is what type of sealant do you recommend when reattaching the outside door frame?

[traveldawg]

I use Lexel around the outside top and side of that door frame once I screw it back into the water heater. Lexel dries a bit hard but it stays clear and doesn't attack dirt. I don't put anything on the door frame before screwing it to the water heater. I leave the bottom unsealed in case water gets in.

Sometimes I seal the inside perimeter of the door frame where it meets the water heater on the bottom and about 2" up the side with black RTV sealant to keep water from getting inside the door frame when rinsing out the tank.

When I changed out my water heater a few months back I put aluminum HVAC tape along the bottom and sides of the inside to keep drain/rinse water out - it leave a nicer looking finish and it seem water tight.

[Chronobomb]

That's a really good Idea. Thank you.

Brent