PEX + '68 Overlander Hot Water Heater Piping Conversion Problem

[Billyjchase]

Dear Forum,
My "plan" is to bring in a PEX hot water line from our house and via sharkbite fittings and shut off/on valves, be able to connect to our homes hot water line while beached at home and disconnect/revert to the AS's hot water heater when traveling. (Hopefully the diagram pic makes sense).

Issue -
- The original copper lines are not .62" OD (PEX 1/2" Di) but instead the copper lines are a smaller .049" OD.
- Im not a plumber (although I play one on TV with SharkBite and PEX lol)

Solutions?
- Does Sharkbite (or similar company) make a fitting that I can replace the thread-on connectors into the hot water tank, that accept a standard 1/2" PEX tubing?

I have plenty of other pics and inner diameter readings if needed.

Im open to sweat welding different diameter copper pipe if its the only option to get me to stanard 1/2" diameter piping... and is even possible. But hoping for solution with less flames involved!J

Any other options anyone can suggest?

Thanks!
Billy J. Chase

[TheGreatleys]

So, you're trying to connect a 1/2" pex line to a 1/2" copper line via a brass compression fitting. You're probably not going to find one piece off the shelf, but a 1/2" compression x 1/2" FIP plus a 1/2" MIP x 1/2" Pex barb would do it.

Since you need to incorporate a tee as well, I'd probably go with something like this:

https://www.homedepot.com/p/Everbilt...0699/207176652

https://www.homedepot.com/p/1-2-in-C...2A-F/100143862

https://www.homedepot.com/p/SharkBit...0LFA/202270581

Probably need to add a valve in there somewhere too, so you can shut it off when you're not connected to shore hot water.

Keep in mind, there's no reason you need to make the connection at the water heater. You could tap into anywhere on the hot side and backfeed.

You'll also want to valve off the water heater cold supply line when you do this to fully isolate the hot and cold side. Otherwise, depending on the relative pressure and available flow on the two sides, you could end up with cold water on the hot side, or hot water on the cold side, passing through the water heater.

[Billyjchase]

Thanks for the info and tips to look out for... but the first and main issue I have to contend with, is that the existing copper water lines are of slightly smaller diameter than the current 1/2" PEX tubing available today (the 2x pics I included, show PEX at 1/2" and the existing ''68 copper water lines that are slightly smaller diameter than 1/2".

Are you thinking I can get a barbed sharkbite fitting that i can insert into the smaller copper lines and then attach the current standard 1/2" PEX tubing to that?

Or am I better off in trying to find replacement thread on fittings (that thread on to the hot water tank (pic included of this area as well), that will accept 1/2" PEX directly?

Thanks and sorry for being a lil dense on this.... Im new to plumbing (and everything else Ive fixed on the AS as I go)!J

Cheers,
Billy

[TheGreatleys]

Use a 1/2" compression fitting to connect to the copper. They're sold in the plumbing aisle of home depot or lowes hanging up in bags. Use a PEX barb or shark bite to connect to the PEX.

Your local hardware store should have all the parts you need if you use male/female threaded fittings to transition between the two types of fittings. There probably isn't one fitting that's going to do the transition from compression to PEX, but you can do compression to male thread, then female thread to PEX. Or, compression to female thread, then male thread to PEX.

[Billyjchase]

Thanks TheGreatleys! I found that the copper line is about 1.5' and threaded on both sides (as it passes through to the bathroom), I was able to discount this short section, Ill take it to hardware store and should be able to get the right parts you mentioned on one trip!
Thanks ... I was "this" close to calling in a plumber (nothing against plumbers!J) but glad its looking like I can get back to pulling this project off!!! Hope to be able to show the finished product here soon! (barring any more questions lol)

[Billyjchase]

Here's the latest...it turns out this smaller than 1.2" DI piping is used in Refrigerators... not water lines... good ol '68 Airstreeam ingenuity ?

I took the water (refrigerator line) to a refrigerator parts store and they although they dont have a thread on adapter to increase to 1/2"

They did suggest if I can remove the fitting thats attached directly to the hot water tank, they might have something that has thread pitch that can help me attached a 1/2" pipe....or, there is a pneumatic parts store conveniently located across the street from the Fridge part store that might work.

1) Does anyone know if the Hot water tank adapter is turned clockwise to remove or if its reversed threaded to remove? I have it soaking with LPS88 to hopefully unfreeze the nut .. if you look at the pics I included originally, its the pic of the hot water tank where the water line attaches to the hot water tank....I need to remove that and see if there is adapter that can thread in and exit to accept 1/2" water line.

If anyone has encountered a similar situation with getting their old hot water tank to accept 1/2" piping, please let me know.

Thanks,
Billy

[TG Twinkie]

The water heater has 1/2" female NPT. That is pipe thread.
In your pic unscrew the dark colored fitting. It will be easier if you disonnect the copper pipe from the flair adaptor.
Every thing is right hand thread.
Righty=tighty
Lefty=losey.
I use the flexible braided stainless hoses to connect all devices. Sinks, water heater, toilet.