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General Plumbing and Gasfitting Talk => Plumbing => Ask Plumbers (Trade) => Topic started by: leaky on May 21, 2011, 05:02:46 PM

Title: reducing valves
Post by: leaky on May 21, 2011, 05:02:46 PM: When eliminating a header tank on an open vented low pressure system with a hwc at ground level,If you don't have good access to the hwc,is it ok to install a pressure reducing valve in the roof cavity above cylinder? will it still work effectively? or does it have to be installed at a low level to work best?
anyone?
Title: Re: reducing valves
Post by: Plumber on May 21, 2011, 05:05:44 PM: Hi Leaky

What are you intending on doing, HWC open vented or will it have a relief (vacuum relief) valve e.g 7.5?
Title: Re: reducing valves
Post by: TS on May 21, 2011, 06:49:02 PM: It'll be fine leaky. Done it a few times myself without any issues.
Title: Re: reducing valves
Post by: leaky on May 22, 2011, 07:56:51 AM: thanks.
Title: Re: reducing valves
Post by: leaky on May 22, 2011, 08:05:20 AM: TS- The installation is still open vented.the pressure seems to be really crap though as i have installed the brand new reducing valve just above cylinder,but wondering if i installed it at base of cylinder,would it get more flow because at the moment the flow is crap.
vent pipe would be a good 3.5 metres.
i mean it works but can it be better?
Title: Re: reducing valves
Post by: roberto on September 10, 2011, 09:29:50 AM: if you install the reducing valve in the ceiling/above the roof line - thats ok, just a pain when it comes to replacing the washer or servicing it, the only way to get better pressure would be to install a pressue relief valve on the vent, just make sure you dont have a wetback!!!!, if u ensure both valves are well insulated with wool lagging or similiar, and make sure they are the same or a lower rating than stated on the hwc and you should be fine