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General Plumbing and Gasfitting Talk => Plumbing => Ask Plumbers (Trade) => Topic started by: roberto on June 06, 2012, 10:28:02 PM

Title: pressure reducing valve location???
Post by: roberto on June 06, 2012, 10:28:02 PM: Would anyone recommend installing a prv in a ceiling to replace the supply tank or install it below the hwc in the cupboard?

I am going to increase the hot pressure for a costumer soon and thought I might make the hot and cold equal to the new shower mixer (methven celeste), by installing a 3 in one valve with a 3.7m prv and then combine the two outlets that are on the supply tank (cold feed to shower and to hwc), lagged of course

she has a open vented wetback system, was also thinking I might increase the hight of the hwc exaust??? :-X

cheers.
Title: Re: pressure reducing valve location???
Post by: integrated on June 07, 2012, 05:53:03 PM: i would throw it in with hwc - nothing worse than having to crawl through a ceiling space or under a floor to find and adjust a prv

gives better accessibility and better protection from freezing also
Title: Re: pressure reducing valve location???
Post by: roberto on June 07, 2012, 08:52:33 PM: yeah i see where ur coming from, i just want to avoid a unequal system,so I dont have to go back and put the jet back in the shower mixer that ive already taken out....
Title: Re: pressure reducing valve location???
Post by: integrated on June 07, 2012, 09:57:28 PM: you can still do what you want to do depending on the existing plumbing

normally in my experience the high pressure feed to the ceiling tank and low pressure hwc feed went up/down through the hwc cupboard - if this is the case then:

- bridge the low pressure feed to the hwc and low presure feed to shower in the ceiling space
- use the old high pressure feeding ceiling tank that goes up inside hwc cupboard to supply 3in1 & prv to hwc inlet
- take a tee off after prv and connect to old low pressure feed to hwc which is now equal low pressure supply to shwr

should not have to touch hot supply unless installing temp valve then additional tee required (also after prv)

of course this all depends if pipework travels up/down hwc cupboard!!

Goodluck!!
Title: Re: pressure reducing valve location???
Post by: o2b007 on June 08, 2012, 08:32:21 AM: I would check how the wetback is feed, If it is a clossed loop it will also be feed off the header tank otherwise intergrated has it bang on.
oh and if there is no tempering valve you should talk them into putting one in just make sure that it suitable for the wetback.
Title: Re: pressure reducing valve location???
Post by: roberto on June 09, 2012, 09:22:26 AM: hey, no its not a closed loop wetback, there are uncommon here.
Title: Re: pressure reducing valve location???
Post by: qeplumbing@gmail.com on October 28, 2012, 01:17:23 PM: Keep in mind that the pressure from the prv to the cylinder will increase by about 2m head pressure once going through the prv dropping down to the cylinder.
Always a lot to keep in mind with maintenance on older systems hey mate!! :)
Best to put it in a location close as possible to the cylinder.