Rerouting copper wet return

mookie3333

I have a wet return that is way too far from the basement wall - sometimes a foot or more. Looking to refinish the basement, this doesn't make much sense. I want to cut out the old return and re-route it . So what's the process? Anything I need to look out for? Just shut off the boiler, drain, and cut the old copper out and solder the new run? Since the return is lower than the boiler drain, I'm guessing when I cut the return, I'm going to have a floor full of old cruddy water. Any tips to avoid this mess? Thanks guys.

Jamie Hall

So long as the new return is always below the water line in the boiler, you can route it pretty much where you want it.

As for the mess on the floor... well, if there is a boiler drain somewhere with a hose bibb on it, use that and run the old water out the door (or pump it out). If there isn't a boiler drain with a hose bibb on it, put one on as part of the new drain...

mookie3333

Yes- I have a hose bib on the return right before it goes back up into the hartford loop. Coincidentally, I am installing a basement bathroom and have the opportunity to route a hose into the main drain which is below the slab (Gravity flow). However, should I be concerned with all that crud going into the main drain? I guess if I have to, I could always rig up some kind of mesh filter ...

Second - I have a location where the return will be crossing a little walkway leading to a closet door. Could I trench the slab, and bury the return for ~3-4 ft and then come back up above slab?? Or is that kind of thing discouraged?

mookie3333

Also, I'm not entirely sure how a bibb allows flushing of the wet return. If I run a hose from the bibb to drain, and turn on the water supply, wouldn't just the boiler, and the little section between the boiler and bibb be the only section that gets flushed (see image in green)? What happens to the rest of the return (see image in red). Thanks guys.

Jamie Hall

Yes you can trench the wet return under the doorway. The way to arrange things so that that bit of return you have shown in red can be flushed is to put a cleanout -- a T with a plug -- at the far end. Then you can take the plug out and flush it. Or another hose bibb.

As to the boiler water going into the main drain. Usually not really a problem. You certainly can rig a filter for it -- old panty hose works pretty well -- if you think there's a lot of solids in it.

Danny Scully

You need to install isolation/purge valves in either side of the wet return @mookie3333, like this.

mookie3333

Great - I know exactly what to do now. thanks guys for all your help!

EDIT: Danny Scully - is that black pipe? so what material is preferred, black pipe or copper tubing? Mine is currently copper tubing, and looks to have been replaced ~20-30 years ago.

Danny Scully

I prefer black pipe @mookie3333, but that’s just me. My theory is that steel return lines im replacing lasted nearly 100 years, no reason to think the new ones can’t. Especially if you schedule annual flushing. Plus it’s more manly

Gsmith

Make sure you can flush out the part of the wet return you lower (install hose bibs or T's and valves) at both sides. Remember all the "crud" you found in your existing returns will eventually build up in the lowered part of your new return.

JUGHNE

IIWM, I would drain out possible out of the hose bib. Then cut the line right there and be ready with a wet shop vac.
As you chop up the sections if you have some newspaper plugs ready that will keep a lot of sludge isolated as you carry out the pieces.

Would you let us know how the copper fared for its 20-30 years of being a wet return? Give it the big pliers squeeze test.