[Capnted]

Thanks. Great responses. At least I know it takes valves and I'm not missing something obvious & simple--or a hidden filler opening on the top of the tank.

When I plumbed a new hot water tank, I left a couple of stubs with gate valves on them, so I think I've got it. I added a "T" to the main line to either push water into the tank from city water or route water from the tank into the pump.

I found the air vent by overfilling the tank.

I suspect that with a couple of well-placed check valves it might be possible to change from city to tank and back without making manual valve settings, but this will work.

It occurred to me that if we all pooled our manuals & Newell or someone in the group scanned them, we would have a wealth of info on classic coaches. I have a lot of the original paperwork on mine, but no plumbing diagram.

When I win the lottery, I'd like to at least move from the 70's to the 80's. But sometimes it's fun to pull into a campground & have people recognize the magic Newell nameplate even tho it's more than 30 years old.

Ted