I trolled through some searches, but couldn’t dig anything on this.
BIL is adding living space over detached garage. His well doesn’t produce much water pressure and he’s worried about adding more space. He knows when that new shower clicks on, the water pressure in the house will be gone.
He had a plumber suggest a holding tank and I’m curious how they work. A normal hot water heater fills when the hot side opens, so something equivalent to that wouldn’t do anything. Do they have electronics that keep the fill side valve closed until they run dry and then click on? What size would be adequate for a single bath use – 50 gal? Should he consider burying a larger tank and serving both the house and the new space with the single tank. I’m sure he’d like more pressure in the house.
MERC.
Replies
A holding tank will not help with lack of pressure. For more pressure he needs a bigger, better pumps.
Only with lack of flow.
Is the pump too small or does the well not produce?
Now if it a low producing well one system is to use a large holding tank. Often vented. Level controlls in the tank control the well pump along with lockouts to prevent over pumping.
Then that tank feeds a supply pump with a pressure tank and pressure controls on the output.
In my neck of the woods, the holding tank serves as a "buffer" of sorts in the well water system. The volume of "standing" water devreases cycling of the pump based on demand, and also lets the pump run at its optimal capacity (any rapid change is mitigated by the tank's volume).
Folks with shallower wells (for whatever reason) locally have to contend with some medium strong taste & smell issues (minerals, mostly). These folk often use oversized holding tanks to let the mineral precipitate out, or outgas from the water.
Your plumber's suggestion might make sense, if the HT was going in the attic, where it would add "head" to the entire water system. The HW tank in the basement would be at the bottom of a 1 or 2 story water "column" which would "fill" the CW and HW systems similarly.
Now, I seem to recall seeing an article (somewhere, sometime, yeesh) on using a pressure tank on the house side of a holding tank. The well pump only worked to fill the HT, the water pressure was regulated by the PT, and that this worked because the HT kept a fairly uniform "head" pressure on the PT. Or, I could have that clean backwards.
Get at least a 300 gallon storage tank.
Basement, yard, wherever.
Let the well fill up the storage tank.
Between the storage tank and the house set another pump and pressure tank.
Problem solved.
Even a cheapo unit like this, can do the job...
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=47906
The person you offend today, may have been your best friend tomorrow