New Water Main Install: Turn Off Boiler Autofeed Ball Valve?

D107

Getting a new water main tomorrow. I figured before the water gets shutoff i should close the boiler autofeed ball valve so all the water in the system atays there. We also have a turbomax reverse indirect. Should i also close the hot and cold water ball valves?

EBEBRATT-Ed

Close them it can't hurt but also switch the boiler off

HVACNUT

When the work is done run a bathtub on cold until the water is clear. Then run it another 5 minutes or so. Shut off the tub. If you're able, remove the aerators from the faucets and flush all faucets with cold. Then repeat using hot water. If you have an ice maker, dump the first couple batches. Run the washing machine and dishwasher empty. You wont believe the gunk that's attached itself to the walls of the piping over the years. Flush flush flush.

D107

@HVACNUT I was thinking I could avoid flushing everything if, when the work is done, I just flush the basement slop sink faucet, so that would be the only place where the gunk would be able to go--channelling everything to that faucet. House piping is copper from the early or mid-80s.

Jamie Hall

D107 said:

@HVACNUT I was thinking I could avoid flushing everything if, when the work is done, I just flush the basement slop sink faucet, so that would be the only place where the gunk would be able to go--channelling everything to that faucet. House piping is copper from the early or mid-80s.

That's a good idea -- but flush everything else, too. You'd be surprised...

STEVEusaPA

Now's a good time for some filtration to the incoming service-strainer especially, and maybe even a prv for the whole house.
In one town I serve (where my father lives), they updated the towns' mains. Everybody's pressure jumped from the 60's up to over 100psi in some places.
Plus lots of sediment in their water heaters, which I'm sure has shortened their lives.
I did the above, then flushed his water heater (thanks to Larry's excellent book).
https://heatinghelp.com/store/detail/the-water-heater-workbook-a-hands-on-guide-to-water-heaters

D107

@STEVEusaPA Yes I have an older version of Larry's book. We had a Watts PRV inline and will be replacing with new of the same. This would be the best time to get the filtering done, but haven't had time to research it, and this plumber basically does the big stuff--via the boring method, runs the copper coil. i'll have to remove part of the sheetrock wall go make this area more serviceable.

D107

Thanks for all those timely replies. All went smoothly; got maybe a few gallons of brown water, some bursts of air. Getting it mostly out of the bathtub first--plumber's recommendation--and then all the other fixtures as per the Wall's recommendation.

In the process they discovered that at the valve by the curb where the city line is attached, the installers of the new main twenty years ago had neglected to tighten the city connection fully--more than a complete turn deficient. Plumber said he's surprised the line wasn't leaking or having other problems; water dept opined that they may have been afraid to tighten too hard and crack the galvanized on the other side of the valve.

Also noticed was that though the requirement here is for the water main from curb to house to be buried at least 42 inches, from the curb to the city main, the 3/4" pipe rises at least a foot or more to attach to the city main from the top. To do that it has to loop over the main, so very likely the actual depth of the main in places is 36inches or less--northern Westchester.

They cut out a sample of my 95 year-old galvanized line. Better shape than I would have thought--at least on the short segment they showed me. Not so much thinning of the diameter, but plenty of rust inside and out and raised areas of loose corrosion that surely must have been responsible for some of the brown staining on our shower walls. Now the main pipe walls are smooth and will probably be delivering cleaner water more efficiently. I lowered the pressure from 60 to 50 without noticeably lowering shower intensity. So definitely worthwhile to do this.

Getting electrician in soon to verify grounding. Since the boring method was used, the original galvanized is still in place inside and outside the house, so probably still useable as a ground. Electrician can keep grounding cable from buried probes attached to old main, new main and water meter, prv and a few feet of the inside copper piping.