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General Plumbing and Gasfitting Talk => Plumbing => Ask Plumbers (Public) => Topic started by: Dean on March 03, 2009, 10:25:39 PM

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Title: Water supply - 50m run
Post by: Dean on March 03, 2009, 10:25:39 PM
Hi there, I'm wanting to run a 50m pipe to supply a 1 bedroom, 1 bathroom house. I'm on bore water, and have a pressure tank set up (I think about 200 to 300kpa, or 30 to 45psi). There's a gradual elevation of about 2 metres over this distance. I can connect to a 32mm spare outlet from the pressure tank. To obtain the best pressure and water flow, how would I go about the pipe sizes? Starting at 32mm, over what distances should I reduce the pipe sizes gradually? Am planning on just running alkathine pipe. Appreciate any advice.
Title: Re: Water supply - 50m run
Post by: worker on March 04, 2009, 12:31:15 PM
the type of pump you are using is a very important factor as that determines the volume supplied and the pump curve (pumps lose their effect over long distances dependant on tpye), however, google 'boxes formula', this is used for calculating  diameters of supply pipes. If that crazy calculation throws you
Then reckoning can be used. I reckon with my almost expert opinion (been Qualified 22 years) run the largest dia. you can ie; 32 all the way, if not then 1x25m  roll of  32mm and 1 25m roll of 25mm the cost difference between 25 and 32 aint that great from your rural supply merchant, they're often cheaper than plumbins supply merchants. p.s. if you oversize now you will be able to increase the size of you house later.
Title: Re: Water supply - 50m run
Post by: Dean on March 04, 2009, 09:23:14 PM
Hi there, thanks for your quick reply. The pump I'm using is a 3 1/2h Davies. If you're in the Auckland area, I wouldn't mind any ideas on who would be well priced for purchasing alkathene piping. Cheers for the suggestions, will look into 32mm alkathene.

the type of pump you are using is a very important factor as that determines the volume supplied and the pump curve (pumps lose their effect over long distances dependant on tpye), however, google 'boxes formula', this is used for calculating  diameters of supply pipes. If that crazy calculation throws you
Then reckoning can be used. I reckon with my almost expert opinion (been Qualified 22 years) run the largest dia. you can ie; 32 all the way, if not then 1x25m  roll of  32mm and 1 25m roll of 25mm the cost difference between 25 and 32 aint that great from your rural supply merchant, they're often cheaper than plumbins supply merchants. p.s. if you oversize now you will be able to increase the size of you house later.
Title: Re: Water supply - 50m run
Post by: kiwichris on May 02, 2009, 01:40:01 AM
It's a bit of a wary situation

Personally, I'd advise against doing ANY plumbing work if you are not a craftsman plumber or register D/L

You could get in a lot of trouble with the council!