Mains water pressure test. | Plumbing Zone | All Other Country's | Plumbers Forums

Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws

Mains water pressure test.

Post thread
Post reply

Discuss Mains water pressure test. in the Plumbing Zone | All Other Country's area at Plumbers Forums

P

pete23

Messages
37
Hi guys!
Silly question I'm sure but voices in head sowing seeds of doubt so apologies if a dumb waste of your time. However, I need to check the mains water pressure before installing a RO Unit. Need to know if need a booster or not. So, do I just buy a mains water pressure gauge (seen one on Toolstation for about a tenner) and then screw on to the outside tap? Then just turn the tap on and watch the gauge? Run for how long? Obviously the tap should either have a check valve built in or one should be on the pipe run. Tap is a pretty old tap so would imagine it doesn't have built it. Will move washing machine to check pipe run. I'm guessing if I can't see one then I shouldn't use the gauge outherwise back flow could do some damage, maybe to the combi??? Not to mention probably breaking water regs? Any advice would be greatly received as am fairly fresh to all this. Many thanks and loving the forum. Pete.
 
Sort by date Sort by votes
On a RO filter it works on pressure on the membrane etc ! But with poor water pressure it will just be slower to make up the pure water ! So hence peaving it running longer ! So i say fit is and see what its like making water ! Alot of people do then they judge from that if they would like a pump or not ! The double check valves in garden taps dont last long anyway even if it did have one ! But i dont think u require one on a RO FILTER ! its just a washing machine connector.
 
Upvote 0
Thanks for replies guys.

Hammers4spanner - I've just completed my level2 tech cert and working towards level3. Also looking to work with someone to gain NVQ, but in the meantime trying to do little bits for friends and family to try and gain experience/ practice. So, to answer your question, no not a plumber as such as I'm aware the tech cert is far from calling myself a plumber!....but hopefully one day!?

As for the checking of water pressure, was just thinking about testing it before installing so if it took an age to run the RO unit I could use the test as an aid to troubleshooting. Also to gain some practice for any future plumbing issues. Not to mention another excuse to buy another tool!? Was just concerned as to whether I had the right idea about connecting to outside tap and turning on. For how long?? Just also thinking 'what could go wrong if I do this??'. Obviously you experienced guys don't always need to do that? Sorry if seen as wasting anybody's time or if I shouldn't be posting such rubbish! Pete.
 
Upvote 0
the test will only tell you the standing pressure.
you would need to open another cold tap in the house, that would be the working pressure.
 
Upvote 0
Be suspicious if pressure does not drop a little when open a tap elsewhere , as the imfamous check valve may prevent flow so you dont' see new lower pressure at measuring point
 
Upvote 0
Thanks for the reassurance guys that my question wasn't too daft.

On31ll - Think it's a 3 stage filter system. Has two chambers at the bottom and the two canister type tubes on the top. Am assuming either 2 or 3 stage but as I have never installed such a piece of equipment that's another reason for all my concerns/questions. Have you installed these units? If so, any hints or advice?

Cheers for all the responses, especially from Santa....must be a busy time of year!?
 
Upvote 0
installed a few RO units. basically all need to worry about it feed,waste and placement.

getting the feed is normally any cold mains feed with a washing machine tap and normally onto this screw a type of tap connector with the reduced pipe fitting on the other side. if the only and best option is the washing machine feed then you can use one of these. most of the RO unis come with a little clamp self cutting tap thing. upto you if you use this but i say dont ! they are rubbish.

Washing Machine Y-Piece 3/4" BSP - Osmotics Ltd

just remeber that you want to be able to isolate the supply so if its behind a washing machine etc it can be hard and somtimes impossible for the homeowner to pull out the washing machine out etc to isolate. also fitting a valve before the RO unit means that you can isolate it to service (change filters etc) i use these type

Inline Ball Valve 1/4" - Osmotics Ltd

the next is waste. the waste on RO units is quite alot. the waste is at a small bit of pressure but nothing special alot of the kits come with a saddle clamp plastic thing that will hold the pipe onto a stand pipe for a washing machine, this is the easiest way.

1/4" RO Drain Clamp Saddle Kit for Reverse Osmosis Water Filters, Reverse Osmosis Water Filter Components & Fittings

next is ocation of the unit. if the unit if in a shed etc then it needs to be insulated. freezing will ruin the unit. crack the housing and ruin the filters. on this i will assume its in a kitchen unit, basically theres a bracket u drill 2 screws and hang it on them and tighten them up. all i can say is that if its gonna be you changing the filters then screw a piece of timber to the the unit and then mount the ro filter to this. it holds the unit off the unit back that little bit further so u have enough room round the filter housing to get a good grip. also do not mount the RO filter to the back of a unit the wood will not support it !! mount it on the side of the unit using screws that dont penetrate right out the side. remeber when siting the unit that every so many litres or every 6 months whichever comes first the filters need changing so make it easy.


i asked how many stages because there are many different set ups avalible upto 6 so far. and normally if the filter has di-resin you would take this out if it was for drinking water. alot of fish keepers use the di resin for a final stage to polish the water. i dont think there is a problem leaving in the di-resin but think its adds to the taste.

also i would make connections to water and drain first and before inserting the filters i would hook it up and give it a try so there is no hairline cracks in the housing etc. because if there is there may be a problem gettin new part etc and drying out a RO membrane ruins it and can be a pain to remove without damage.

take a note of the make,GPD, NO. of filters and what ones and keep it in your customer records so when they ask for a service you can pre order the filters and go there and change them all in one go. might even impress them. also removiing the RO membrane its a pain to grip as it has a runnber seal holding it in just take a pair of long nose pliers. just a tip i suppose.

need any help just ask and me and the others will try to help

MODS i dont have anything to do with the business linked, there reference only
 
Upvote 0
Wow! Thanks for all the advice on31ll, and judging by the time of your post you too search this forum at stupid-o'clock!?.

As for my installing and intentions of set up I am going a little 'off track!'. Firstly I'm installing this for my brother who is using the unit to make his own filtered water for his marine fish tank. He has no room to house the unit under his sink, where I suggested having it and also does not have a separate utility room. Therefore we are left with the idea of placing the unit in the garage. As a result, I was intending to run the feed from the outside garden tap? I have seen an adapter that I could screw onto the existing tap which does a similar job to a washing machine 'Y' connector but will allow him to also connect his garden hose to so can still water his garden etc. I would then connect the 'tap connector' to this and run direct from the outside tap configuration to the garage in the smaller 1/4 inch pipe to feed the unit. (Roughly 2metres and under the decking). I am aware that this run of pipe would need to be insulated to prevent freezing, perhaps using lagging? Any ideas? Once linked up to the system the next hurdle is the waste. Again intending to run the waste through the garage and into their water butt? Or into the drain for the garage guttering? I was wondering if this would be best to install a check valve on the waste outlet, especially if running to their water butt?

As for the pure water, again they were hoping I could run to another, covered water butt stored inside the garage so they could store it until they need to do their water change in the fish tank.

I am aware the garage is a risky place to store the RO unit due to freezing but will intend to insulate as best as possible and maybe house in a cupboard or something? Again any ideas?. I was also going to install a service valve on the feed once inside the garage in order to help when doing maintenance to the unit.

Think that's about everything!? If you could see any potential problems with this idea I would be grateful if you could point me in the right direction.

many thanks once again for all your help and support.
pete.
 
Upvote 0
i am on the forums at crazy hours as i travel to sites etc in the day and work nights on certain sites as thats all that is allowed.

has your brother already bought the RO unit ? if not maybe look into more stages if he would like etc ? alot of fish keeping including marine keeper use di resin but this can also be added to a filter at a later date anyway.

can you not access the pipe internally and have its own seperate run ? garden taps should really be isolated etc in really cold weather to stop freezing etc. but water changes on fish tanks etc need to be done all year round.

as for storing the water you want to keep in a water tight container really so it doesnt turn stagnant. also if the garage is really cold then insulation direction onto the filter will only work to a certain degree. it will and can still freeze i suggest on the certain times of the year bringing the filter into the main part of the house and hook it all back up when needed !
 
Upvote 0
Hi pete23 (& on31ll)
This is in no way a criticism of you personally, as you are asking question & as you recognized in your first posts on the thread you are not fully qualified.
I point this out both for your future reference & to show others the dangers that can lie out there in plumbing if you are not fully qualified & carry out work which appears simple & uncomplicated without a full understanding or training.

According to (Law) The Water Supply (Water Fittings) Regulations 1999, Part II. 5 (1) The person who is proposing to install (e) "a unit which incorporates reverse osmosis" (a) shall give notice to the water undertaker (supplier) that they proposes to begin work; (b) shall not begin that work without consent........... (c) shall comply with any conditions to which the undertaker's consent is subject.

So before the installation can take place you must notify your water supplier of your intention to install one of these units, this is for two reasons 1. They can waste lots of water if they go wrong & 2. They can contaminate the mains water supply, again if they go wrong & so will require backflow protection measures to protect the supply system.

It is frustrating but there is no requirement on manufacturers to provide details of what is required to install there fittings & equipment so that it complies with the Law of the Land & of cause ignorance of the Law is never excepted as a defense.
 
Last edited:
Upvote 0
What back flow protection device do you fit (or do they come with one already installed) on31ll ??
I have never fitted one of these units as you say they are becoming popular, I had to check with WRAS as to what the fluid category is for them.
 
Upvote 0
Upvote 0
on31ll said:
there are john guest ones. i carry alot of the smaller john guest stuff around

John Guest - The World Leader in Push-fit Fittings, Pipe and Plastic Plumbing Systems - SINGLE CHECK VALVE - Imperial

they are perfect on the installs like this one where there isnt a cold mains run so to speak I.E coming off the garden tap.

i wouldnt know what the catagory is but its just purified water. so not to much of a risk. only a risk it its not used and gets warm then legionella etc etc.
Click to expand...
WRAS mailed me back this afternoon & confirmed Cat 3 domestic ones & 4 or 5 commercial so must be a double check not single for the ones you are doing.
 
Upvote 0
might sound like i am trying to bail myself out but 9 times out of 10 i do fit a double check onto the pipework but on the ones that are fitted then taken off after use because there is no place permanant to fit it i use the push fit single check. but i will fit a double check as standard to future ones fitted and serviced.

in all fairness and all diagrams ive seen there has never been a check valve but hey what do the manufactures care.

also you say a test point how would you fit a test point ? just a tee in between the two single check valves ?? couldnt u just miss out the test point as its pushfit ?
 
Upvote 0
Wow, thanks for all the info and the warnings guys. (Been away and couldn't post). So, looks like a phone call to the local water supplier then? Seems a bit crazy about the contamination risk though as surely we are making 'purer' water?? Would always expect to put some kind of check valve on anything coming off mains anyway but been very interesting seeing all your posts. Sometimes can learn more on here than in the textbooks and in the classroom.

Thanks for everything!
 
Upvote 0
Hi pete if you think about what these filters do it may not be such a surprise, to get the pure water out of the filtered side all the stuff that they take out is kept back on the mains supply side of the membrane & you may be surprised at just how much say organic matter can be in the mains water supply but all the time it is passing through with the right amount of chlorine there is no danger but allow it to build up & it could pose a risk.
As far as just installing check valves to protect system from any kind of risk can I humbly suggest that you get on a Water Regulations Course or carry on training through to level 3.
PS Most water undertakers require a written notices which is simple to do may be check out the WRAS web site for more info on this & the Regs.
 
Upvote 0

Similar plumbing topics

C
  • Question
Noisy main cold water pipe, my plumber hasn't heard this before.
I had a chattering float valve in the loft...
Replies
2
Views
490
Jerry
J
B
  • Question
How to balance water pressure in taps
Marcin whilst your understanding of a pressure...
Replies
2
Views
868
Ben-gee
B
K
  • Question
Mains boost pump in top-floor flat
Probably all off one main hence your problem...
Replies
3
Views
888
ShaunCorbs
ShaunCorbs
P
  • Question
water pressure problem, unvented system
I would suggest getting a G3 plumber in to...
Replies
9
Views
602
Rtplumb
R
N
  • Question
Unvented water heater
Please let us know what it turned out to be!
Replies
5
Views
894
Lou
Lou
Back
Top