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K

keith1967

can anyone tell me how i can test the pressure of my water, is it only possible by buying a £50 pressure gauge?
 
hi kieth
Monument Tools® Mains Water Pressure Test Gauge - NoLinkingToThis, Where the Trade Buys
I hope this helps.
I made my own from a pressure gauge out of an old boiler and some fittings.
Regards
Mike
 
Hi!

I use a monument type pressure gauge but I've also made a piece of pipe with a tee in it for a ball o flow valve with a handle on.

I have a couple of those flow gauge cups they gave away with combi boilers at one time.

So what I do, is connect up and turn on then read pressure gauge for standing pressure, then turn on ball o flow and run into cup until I get the flow I want, then I read the dynamic pressure and the flow.

Don't forget when fitting an appliance it's usually the dynamic or water running pressure that matters not the standing or no water running pressure. The difference can be considerable.
 
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Hi Keith!

Showers are one of the things you do need to know the dynamic pressure and flow rate for. The MIra website probably has a fuller explanation about it. Triton once put out a video about fitting showers that was excellent, there might be something on there. Aqualisa also has some stuff on it.

In short to fit a shower you don't only need to know the dynamic water pressure for the shower but also the flow rate it requires.

It usually states say something like: "2 bar at a flow rate of 15 litres/m"

What that means is that you have got to show 2 bar pressure on the gauge whilst running off water at the rate of 15 litres per minute. In point you have got to measure two things at once. That is why I made the gizmo.

You can of course buy the real McCoy but beware it costs a shed full of cash.

The easiest thing to get of course is the copper pipe and fittings, its getting a combi cup or a flow measuring jug for a reasonable price that is hardest.

You can of course use a 1 pint milk bottle and a stop watch or even a kitchen measuring jug and a stop watch and just time how long it takes to fill and what the pressure is.

Buying the real equipment is a bit pricey if your only ever going to use it once for putting a shower in your house. And don't forget you usually only have to measure it once.

Incidentally measure it as close to the point you intend to put the shower in as possible. Don't rely on a kitchen sink or washing machine point measurement.

The difference between a downstairs and upstairs pressure can be quite a lot.

I usually pipe the job up and test from where the shower is going to be fitted.

All this is assuming your talking about an electric shower.

Err! A good tip, is that one of the first things a shower company checks if anything goes wrong with the shower is the pressure and flow rate. If they aren't within specs they can refuse to fix it.

Anyway, good fortune and hope this helps. Possibly some other guys on the website may have some other ways you can do the same thing.
 
shower is a thermostatic one, going through a combi,

actualy, its an all in 1 singing n dancing shower which comes with tray, glass cabin ,and plastic interior which has built in jets, shower head, seat and anti steam mirrors.... im also worried about the ease of fitting these and the long term problems that could occur. if there is a leak or breakdown would i have to take the whole thing apart? can i get spares?
 
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Hi Keith,

I would check it out very carefully.

The reason is that you are tied down to the flow rates of the combi (about 8 litres a minute usually) and you can't alter that, unless you replace the combi with a bigger one with a higher flow rate.

Many showers of the sort you describe usually require something like a flow rate of 11-25 litres per minute. With a min 1 bar and 5 bar dynamic or water running pressure.

And you can't put a pump on a combi to bump up the pressure either.

You also want both the hot and cold pressures and flows to be the same.

So your tied really to the showers you can get for a combi.

Although Triton do make various showers of the kind you mention, that will work with a combi. Please remember that the pressures and flows they state are usually the minimum.

They also ask for about a 52 degree's minimum temperature rise on the combi, with a given flow rate of about 3 -8 litres minimum.

Temperature rise is only the difference between the temp of the water coming in and it going out as hot from out of the combi.
And don't forget that the mains cold water to the shower on a combi system also supplies the combi hot.

So turn the cold water on to see how much it effects the hot from of the combi. I know on some jobs turning the mains cold water on nearly stops the hot.

So if your not careful when you fit the shower you may find you've got the correct pressure on the cold side but not enough on the hot.

The thing is highering the cold water flow or pressure into a combi to increase the hot flow can make it noisy, as well as dropping the hot water outlet temperature by making the cold water flow too fast through the combi, before it has had chance to heat it up enough to give a minimum 52 degree temperature rise .

I know all this may sound a bit complicated but it isn't really. All your trying to do is make sure the shower gets enough water at the right pressure.

If your site conditions meet or exceed the conditions as stated for the shower then there seems no reason why it should not work well.

As to spares: If the shower is made here or its a well known make then spares are not usually a problem. And although showers may look different, they are all basically the same and have been for years.

Yes they can be complicated to assemble but they don't usually leak very often.

Hope this is of help?
 
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The Monument guage also screws onto garden taps. If it can be modified to allow flow the water can spill into the garden and flow pressure can be measured.
Thanks for the posts above. They help to answer my recent post on mains pressure v's flow.
Martin
 
shower is a thermostatic one, going through a combi,

actualy, its an all in 1 singing n dancing shower which comes with tray, glass cabin ,and plastic interior which has built in jets, shower head, seat and anti steam mirrors.... im also worried about the ease of fitting these and the long term problems that could occur. if there is a leak or breakdown would i have to take the whole thing apart? can i get spares?
unless you have a very high flow combi id say you cant fit one of these showerhigest flow rate your gonna get from a normal combi is 12 litres
 
Well if you have a combi ,when system cold open filling loop and see if you can get boiler presure gauge up to 2 bar,if so you have over 2 bar in presure on mains,then release presure back to 1,5 bar through drain cock or radiator vent


what make is it,model,how many body jets does it have
 
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