An existing three-season vacation cabin has its water supply coming underground into its crawl space. Water is via a spring tank, and there is a pump in the crawlspace. Lines are pitched and valved so that when the place is closed for winter, everything can be drained.
A new addition is planned, to be added out from the cabin, with everything on a frost-protected shallow foundation. A well will be drilled and the spring abandoned, thus the new well will supply the bathroom needs of the existing cabin, and the new kitchen/bath/laundry of the new work.
What is desired is a means of piping and valving so that the new part can be used occasionally in winter during deep freeze snow and ski season. When doing so, the new part would be closed from the old with a weatherstripped and insulated door.
With the new well setup and the pump down in the well, shouldn’t we bring one supply line into the new addition through the slab, and have a main valve, then a branched valve taking water underground over to the old cabin crawlspace? We could pitch it so it could be drained.
What is done when shutting down everything, so that the little piece of water line coming from the well and up through the slab is dry? When a well pump is shut down, it cannot hold a head above it, can it?
Replies
Place the valve that controls the old water supply in the insulated space, then soon after that, install a silcock in the insulated space that you will use to drain the system. Not to state the obvious, but, make sure that there is an easy access route to get to the valves or shutting it down may be overlooked. The only problem I can see with doing this is when it is sold. Most people will see the whole thing as a year round residence and not even think to drain the old part.
Why not just heavily insulate the old lines?
"It is what it is."
You should use a 3-way ball valve to feed the old system. Shut the old side off and it will automatically drain.
"What is done when shutting down everything, so that the little piece of water line coming from the well and up through the slab is dry? When a well pump is shut down, it cannot hold a head above it, can it?"
Sure it will.
You have a check valve on the line otherwise the pressure tank will try to drain back through the pump.
I am not sure where those are installed on an summersiable pump system, but would get right on the discharge.
Off the top of my head I think that the best thing would be lots of insulation around the riser and valve to keep it "underground" along with a door or panel for access.
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.