Bypassing tankless water heater in 2021 Flying Cloud

[youknowjack]

The tankless water heater in my new 2021 Flying Cloud 27FB burst a copper coil internally in the unusual freeze we had here in Texas last week. I'm working on getting that fixed, but in the meantime I want to look for any other issues by shutting off the water flow to the heater.

I'm having trouble figuring out how to disconnect/bypass water flow to the heater. I'm looking under the lav sink for a bypass valve but can't find one. I see all the water lines into and out of the back of the heater, and I see the cutoff for the drain line. Wonder if it's possible no bypass/cutoff is installed? I can easily unscrew the supply line from the back of the unit, so I guess I might be able to plug that?

I would welcome any tips from people with experience with these new tankless installs.

Jack

[mimiandrews]

There probably isn't a bypass for a tankless water heater. The reason tank-type water heaters usually have a bypass is to allow winterizing without having to buy 6 gallons extra antifreeze to fill up the tank. The owner simply drains the tank, bypasses the water heater and fills the rest of the system with pink stuff.

Deepest condolences on your freeze damage.

[youknowjack]

As a follow-up for anyone looking for advice later... I did not succeed in a manual bypass, but I did get a replacement part (copper heat exchanger) shipped from Girard (who makes the tankless heater), and a plumber put it in for me. The part was $130 and the plumber cost ... don't ask, a lot more... but I avoided a long wait for an appointment at my dealer service center.

Spring Break trip saved!