Replace water heater bypass valve

[Billy MB]

Hello

The water heater bypass valve is leaking in my 2014 Scamp. I've worked with PEX plumbing in my house and have a PEX crimp tool and crimp fittings like this: https://cantireapp.page.link/hdUrwogo2u385BaU6

Am I okay to just cut out the old valve and install a new brass valve from home Depot and use my PEX crimper?

Or do I need to source a plumber that can make the same fittings that scamp uses?

Thanks!
Billy

[Darwin Maring]

Me, I would get rid of the Scamp stuff and use brass and Pex pipe and crimps.

Is the connections something like shark bite? If so, drain water and see if you can Press the pipe further i to the connection.

[Casita Greg]

From the picture, they look like "Shark-bite" fittings, (which I've personally never cared for,) but a lot of people use them. I prefer PEX crimped fittings.

A bypass, (aka winterization,) valve is not a standard ON/OFF water valve. If you have a single bypass valve, chances are pretty good that it is a 3-Way ported directional flow valve which allows flow, or isolates flow, through the piping systems to allow water, (or anti-freeze,) to flow through the water lines but ideally not into the water heater reservoir. There are several different bypass valve set-ups used in RV's and trailers. You can have a one-valve, two-valve or even a three-valve winterization isolation valve setup. If it didn't have a means to isolate the water heater reservoir from the water lines, you'd need about 7 Gallons of AF instead of one. Flow is deliberately directional in a single vale setup, for the reasons listed above, so a standard water valve won't suffice in most cases. Also, NEVER attempt to turn the bypass valve while the water system is pressurized. It will destroy the valve seat, and usually only takes once. I would think that yours had been turned while pressurized at some time which is probably why it leaks now. Your PEX tools will come in handy, but you will need a new bypass valve. Make sure you get a replacement that matches the one you have. There are several different designs out there with various end fittings. Be sure to source the correct one. They're only around $20 bucks or so.

Now, if it's just a bad Shark-bite fitting, that's easily repairable for little cost or effort.

[Eddie Longest]

Scamp uses type A PEX, it uses expansion/contraction rings, it and the pipe is expanded over the fittings. Tupe A fittings are larger for low flow. Type B PEX uses the crimp rings and smaller fittings. I cut out the Scamp type A fitting and use the type B fittings (big box store fittings) and have had no issues. If you think a crimper is expensive, try buying a Type A expansion tool. I have used crimp rings on type A and type B tubing. That is just my experience, YMMV.
Eddie

[Billy MB]

Thanks for the replies!

I think i'll just go with the Pex tool and crimps I have and replace with a standard brass valve and cut out the Scamp "A type" PEX fittings and valve.

Even though I'm planning to switch to blowing out the water lines with compressed air this fall, I might go ahead and plumb in a proper 3 valve water heater bypass set up so I can properly winterize the hot water side of the plumbing with RV antifreeze. I've found scamps "Gravity" method doesn't really work with on the hot water lines on our side bath.

Thanks
Billy

[Eddie Longest]

If you don't have an antifreeze pick up valve for your water pump, I highly recommend them. I found blowing your lines out first before adding antifreeze uses less antifreeze and gives better coverage. I also blow the antifreeze out the lines when de winterizing. The systems cleans up with less rinse water.
Eddie