Welcome to Plbg.com
Thank you to all the plumbing professionals who offer their advice and expertise

Over 675,000 strictly plumbing related posts

Welcome to Plbg.com and PlumbingForum.com. The best online (strictly) PLUMBING advice, help, dyi, and informational plumbing forum. Questions and discussions about toilets, sinks, faucets, drainage, venting, water heating, showers, pumps, water quality, and other exclusively PLUMBING related issues. Please refrain from asking where to purchase a product, or business, pricing, or legal questions, or for contractor referrals, or any questions not related to plumbing. Keep all posts positive and absolutely no advertising. Our site is completely free, without ads or pop-ups. We do not sell your information. We are made possible by:  

Post New
Log In
How to Show Images
Newest Subjects
 Plumbing help
Author: K5BEAST (ID)

I live off grid. I'm not a plumber by trade but am a seasoned construction worker.

I currently have a storage tank that i fill. Water is moved via a 12v pump. I utilize a 38gal pressure tank running at around 50psi line pressure. It feeds a tankless water heater which feeds a shower and sink. All works fine.

I adding a new master bathroom located level with the pressure tank but about 6ft above the water heater. The master bath will have a toilet, vanity, and a walk in shower incorporating rain fall head, hand held, and 6 body sprays. I'm worried that the water pressure won't be adequate in the new bathroom. How can i raise the water pressure for just the new bathroom?

Post Reply

 Re: Plumbing help
Author: bernabeu (SC)

not practical

the added bath should be 'conventional' with water saving fixtures

your 'problem' is/will be gpm used by shower NOT pressure as the elevation is the same as the tank

1 gal = 8.334#

assuming tank temp = 60 degrees (average due to Idaho) and desired hw temp = 120 (allowing for mixing at tap)

1 gpm = 8.334 X 60 btu/min = 500.04 btu/min = 30,002.4 btu/hr

that is ONE gallon of hot water per minute

? you are off grid ?

- - - -

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"

Edited 1 times.

Post Reply

 Re: Plumbing help
Author: packy (MA)

i'm not great at this but i know you will need 3/4 inch to feed the new shower.

i'm guessing a second pump working in parallel with the first pump will help greatly.

Post Reply

 Re: Plumbing help
Author: LI Guy (IN)

Look at the the GPM ratings for all those fixtures, your problem is going to be volume, not pressure. You're going to need 3/4 pipe minimum all the way from the tank to the fixtures, will your tankless HWH keep up, and how fast will you drain your supply tank? That's a pretty luxe setup for off the grid LOL.

I would stick with the low volume water saving fixtures, or at a minimum go with a really nice massaging shower head and skip the body sprays and rainfall

- - - - - - -

Not a plumber by trade but a fierce DIYer

Post Reply

Please note:
  • Inappropriate messages or blatant advertising will be deleted. We cannot be held responsible for bad or inadequate advice.
  • Plbg.com has no control over external content that may be linked to from messages posted here. Please follow external links with caution.
  • Plbg.com is strictly for the exchange of plumbing related advice and NOT to ask about pricing/costs, nor where to find a product (try Google), nor how to operate or promote a business, nor for ethics (law) and the like questions.
  • Plbg.com is also not a place to ask radiant heating (try HeatingHelp.com), electrical or even general construction type questions. We are exclusively for plumbing questions.

Search for plumbing parts on our sponsor's site:

Special thanks to our sponsor:

Copyright© 2021 Plbg.com. All Rights Reserved.