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e2e99
Jun 8, 2009, 06:58 AM
Hi

I have to replace the main water shut-off for my house. The existing one is the old "screw/unscrew"type, 1/2" pipe on both sides of the valve.

I would like to install a ball-type valve, but I notice that the hole in the ball seems smaller than the other type. Does the pressure or volume get affected by this change ?

Is there an advantage to installing a 1" valve (with reducers) to avoid any potental pressure loss (bigger valve = bigger hole) ?

Thanks

Eric

massplumber2008
Jun 8, 2009, 07:08 AM
Hi e2e99:

You want to purchase 1/2" FULL-PORT ball valve for this application. I would not install a 3/4" or 1" valve at this point... will not serve any purpose.

If unavailable at home depot or Lowe's, stop at a plumbing supply store and ask for the full-port version of this shutoff.

Good luck!

MARK

ballengerb1
Jun 8, 2009, 07:09 AM
That 1/2" ball valve will not appreciateively affect your water volume which is likely low already. You can certainly install a 3/4" ball if you want to but I'm interested in where that 1/2" pipe is coming from, city or well?

Milo Dolezal
Jun 8, 2009, 08:13 AM
Are you sure it is 1/2" valve you are dealing with ? Not larger ?

e2e99
Jun 8, 2009, 05:36 PM
Thanks for the comments.

The pipe is definitely 1/2" copper, it comes from the city main pipe. Pressure is reasonable, but not as great as a friend who lives in a larger town and has 3/4" pipes from the city.

I have found a ball valve with a 7/16" hole in the ball, does this qualify as "full port" ?
(I realize that 1/16" is not much, but I would prefer doing the job one time, as it requires calling the city to turn off the water at the curb).

massplumber2008
Jun 8, 2009, 06:23 PM
Hi e2e99:

PRESSURE differs from area to area as I am sure you know... usually regulated in some way in between 40 and 60 PSI. The VOLUME of water is determined by the size of the pipe and that is what determines water availability when, for example, you use multiple fixtures at one time.

Many water meters from the city come in as 3/4" and I'm thinking these guys would like to see you increase the water piping to 3/4" if available... but for now, to answer your question.. the 7/16" is as full-port as it gets... :)

If you have 3/4" piping into the water meter you could increase the main water lines in the basement... would certainly increase volume availability. It will not increase the pressure whatsoever... ;) Just FYI.

MARK

mygirlsdad77
Jun 8, 2009, 06:52 PM
I would be surprised if your feed line from city service was 1/2 inch. 3/4 inch is the smallest allowed service, but if that's what you have, then above advice is correct. No need to enlarge vavle. Just get a 1/2 inch fullway valve. Gate or ball vavle will be fine, but I recommend the ball valve. Can you post a picture of your meter connections? Im just curious to see how they transferred from 3/4 spud to 1/2 pipe. Never seen a 1/2 inch meter.

Milo Dolezal
Jun 8, 2009, 07:01 PM
Just for my info: how big house is it? How many bathrooms ? What's the pressure ?

e2e99
Jun 8, 2009, 07:42 PM
Ahhhh, I see the confusion. No water meter in my city, so 1/2 inch comes out the basement floor.

There is an underground valve, outside, accessible by the city with a long T handled wrench. This may be 3/4 in 1/2 out, but I am not sure.


Thanks for all the great answers

ballengerb1
Jun 8, 2009, 08:56 PM
Call your city water department and ask what size main they supply to your house, bet its 3/4

e2e99
Jul 27, 2009, 07:17 AM
Thanks to all for your help. I replaced the valve with no problems, the full port did the trick. Great answers, great help.

massplumber2008
Jul 27, 2009, 09:02 AM
Thank you for the update... always appreciated by all!

MARK