I have three questions concerning plumbing some goodies up:
1) I want to run an extra copper pipe to the base of my hot water taps for the kitchen and bath faucets, and shower, and put (a) one-way valve(s) on them, and have the "extra" pipe(s) return to the bottom of the hot-water heating tank. The purpose would be to have the hot water circulate by convection when the taps are closed, thereby providing "instant-on hot" when either of the faucets are opened.
(I am in North Dakota, and it seems in winter that 2 or 3 gallons are required to bring things up to temperature when it is very cold out. I realize it may be expensive to "maintain" these heated pipes, but hopefully not too much more than that big slug of cold water entering the hot-water heater when we run the faucet on initially).
My question - can I run the return pipes into a common header, and use only one one-way valve at the base of the tank - or do I need a one-way valve at the base of each tap? Will I get significant draw-back from the "common" if I use just one check-valve at the base of the tank?. Also, how "light" of a spring would I need in the check-valve - or do I need a spring in it at all?
2) Can I share water-hammer preventers 'twixt the bath sink and shower effectively, or do I need them right next to each valve (The sink and shower are 4 foot apart). Also - does the air-filled portion need to be above the height of the faucets? When I make them up, should I use larger diameter pipe for the preventer "stem", or is the same 1/2 inch suitable?
3) One last question: What do you guys think of that "Copper Bond" two-part epoxy goop for "soldering up" copper pipe??? I have an older house, which is to say all the timber in it is bone-dry and lotsa cobwebs, so I am wary of the open flame of a torch to solder with. Are there any/many "horror stories" concerning this "Copper Bond" stuff, or would you rate it - personally, in your professional opinion - as "Acceptable"?
Thank you for your answers, in advance!
Bruce in North Dakota