Glycerine filled manometer

You will get on with asking questions much better if you learn from what has been disclosed in this thread in that the device you are using is NOT a manometer.

To be fair to the OP. If you think you know what a "glycerine filled manometer" should be. Just pop "glycerine filled manometer" into Google.

Baz

Bob Minchin wrote: [snip]

Are you not sure?

Ok, I agree, in English, which is not my native language, according to Wikipedia: "Instruments used to measure pressure are called pressure gauges or vacuum gauges.

A manometer could also refer to a pressure measuring instrument, usually limited to measuring pressures near to atmospheric"

But Merriam Webster dictionary defines it as "an instrument (as a pressure gauge) for measuring the pressure of gases and vapors" which is as broad a definition as the one in other languages.

But, it was obvious that the broader definition applied here since I was talking of pressure readings far from atmospheric.

Leaving that aside, do we agree that a glycerine filled pressure gauge can be installed in any position keeping the enclosure air tight for reading of several bars?

Indeed, That is how I came to realise what the OP was on about. However just because others use the wrong name and google indexes those erroneous references does not make it correct.

i don't think he cares, he's been told enough times it is a pressure gauge, not a manometer, but he still refuses to call it by it's proper name,

I think all he wants is for someone to say 'yes, it will work fine how you propose' so that when the glycerin leaks out and makes a mess, or the gauge becomes inaccurate, he can blame someone else for telling him it would be ok,

Maybe if he bought a decent quality gauge in the first place he wouldn't have this 'problem'

Not sure really why he 'needs' to measure the water pressure at home, it either comes out the taps or it dosent, what's it matter if for 2 seconds a week it's half a bar below 'normal' pressure,

He says a couple of 'regular' gauges he's used before started reading less than actual pressure, how is he reading the 'actual pressure' and why dosent he just use that for the reading? or pop the front bezel off the gauges and twist the needle to the correct position :)

I would be surprised if you need a glycerine filled gauge in a domestic application. The glycerine filled is to protect the gauge from excessive vibration or pulsing. If you have either, that is so bad that you need glycerine filled it WILL damage the rest of your system.

Baz

It'll vary with atmospheric pressure anyway, that has a range of about 50 mb, or about 5% @ 1 bar, 0.8% @ 6 bar.

But without having the casing vented to the atmosphere when the tube expands the pressure in the casing will rise and affect the reading. They are designed to be used vented. I suspect any offset will be non-linear as the pressure in the casing rises.

Agreed

'Dave Liquorice[_2_ Wrote:

Disagree. When under pressure, the tube deforms (straightens up) but does not expand meaningfully. There is no change in pressure inside the casing

The tone of this reply is not what one should expect in this forum.

The house is connected to a pump that supplies up to 10 bar. There will be a quality pressure reducing valve which does come with a pressure regulation screw mechanism.

I want to have an additional pressure gauge as a redundant safety to avoid bursting or damaging the plumbing in the house in the event the pressure reducing valve fails. Or to make sure that the pressure is above the level required by certain equipment in the house (but may be you could tell that by opening the tap, I cannot)

The pressure gauge that I first got for the pressure reducing valve has failed as confirmed by a Monument Tools Mains Water Pressure Test Gauge connected to a tap which reads the same as the pressure setting in the valve.

Obviously a fixed pressure gauge is a better solution than the Monument Tools tap one, if anything because I may have to use the tap for other purposes. Or do you not agree with that either?

Now, the glycerin gauges that I have seen have the 1/4" BSP thread only at the bottom, which means that if I screw it into the horizontal thread in the body of the pressure reducing valve it will be in a horizontal position. I am trying to avoid cutting the pipe or other more complicated solution to install the pressure gauge in a vertical position.

By the way, pressure gauges do fail, even quality ones, I once had the two pressure gauges in two brand new Worcester Bosch boilers fail at the same time, which caused a major problem.

On Thursday 29 August 2013 20:26 asalcedo wrote in uk.d-i-y:

It's a USENET newsgroup - not a forum...

And I've seen a lot worse for tone :-o

Is that Donny Osmium or one of the others?

forum.

I'd previously missed the OP was a diybanter leach, principally because I didn't understand the questions with the doubtful terminology. So chose to, initially, ignore it.

As the OP rejects anything said, they appear to have made their mind up before posting anyway. Don't know why I bothered TBH.

Indeed, it's been positively polite.

Then may one politely request that one goes forth and multiplies, you insolent vagina!

My wife hits 9.9 reading frequently

%?

a rather ineffective strategy. Cheaper, simpler more effective more reliable measures would be better

NT