permissible drop

[Corgigrouch]

Yup, I just do it automatically whilst the customer makes me a brew... I couldn't remember if it was mandatory

Its NOT mandatory!

But if the customer does not offer me a coffee or tea, then I might have a slightly longer response time to any future calls!

Tony

Mandatory or not it can cover your backside, save you time looking for a leak that you have convinced yourself that you have caused and is a potential money earner so it is wise to do for the sake of a few minutes

Had one customer who had a leak that had filled his cavity.. A badly fitted compression fitting INSIDE the cavity, the work had been done around 20 years ago when they removed a water heater in his kitchen..He was one of those who do anything to avoid paying so we know who he'd have blamed if I hadn't checked before starting work...

 

[scatmanjohn]

I have a question for the engineers here, if youve done a tightness test on an E6 meter and noticed a 9mb drop in 3 mins.....then investigated further & found when you isolated (Gas on) boiler (only appliance in house) the drop was only 3mb in 3mins.....what would be the next course of action?

My next course of action would be to do it all again but this time carry out the test for the correct period of time.

let by = 1 minute
temp stabilization= 1 min
Test period=2 mins

So doing it your way, 9 mBar over 3 mins would in fact be a 6 mBar drop over 2 mins which is acceptable providing there is no smell of gas.

 

[Gastel]

I have a question for the engineers here, if youve done a tightness test on an E6 meter and noticed a 9mb drop in 3 mins.....then investigated further & found when you isolated (Gas on) boiler (only appliance in house) the drop was only 3mb in 3mins.....what would be the next course of action?

My next course of action would be to do it all again but this time carry out the test for the correct period of time.

let by = 1 minute
temp stabilization= 1 min
Test period=2 mins

So doing it your way, 9 mBar over 3 mins would in fact be a 6 mBar drop over 2 mins which is acceptable providing there is no smell of gas.

ZZzzzzzz......always 1 smart arse, 1 min Temp stab + 2 min test = 3min.........

 

[kirkgas]

good post from ChrisR about different permissable drops depending on pipe size as well as meter, i keep forgetting i can now work on 35mm pipe as long as the volume is below a certain lever (0.35m3) i think, the figures given for permissable drop have now changed to 0.2mb for electronic and 0.25mb for water manometer

 

[n2o]

Suppose you encounter a situation similar to this...

Large Domestic Installation

• n2o
• 16 Aug 2008
• 1

..where when only valve B was closed the system volume would be say 0.03m3 and when only valve A was closed the system volume would be say 0.01m3.

Would the commercial ticket be required and, if so, why?

 

[kirkgas]

if the system volume is in excess of the predetermined level you need a commercial ticket as purging has to be done as per commercial procedure, so in the scenario you give i THINK we would have to calculate volume on worst case scenaro ie with all valves open giving greatest volume available, not sure how often it will crop up at work but if a domestic guy encounters a 35mm pipe the first thing he has to do is calculate IV of the whole system to determine maximum volume and then decide whether he is allowed to work on it or not, that is why i suggest he needs to open both valves and work out the whole system IV, the calculation is meter volume + total pipe(s) volume as per diameter and length, + 10% allowance of pipe(s) calculation for all fittings if this calculation exceeds 0.035m3 a domestic can't go any further

 

[scatmanjohn]

Not being smart, just stating facts. The test period is 2 mins. You said it was 3.

What do you do if you get a 2 mbar drop during temp stab period?

 

[ChrisR]

let by = 1 minute
temp stabilization= 1 min
Test period=2 mins

Except when it isn't.
When isn't it (Domestic)

---

So doing it your way, 9 mBar over 3 mins would in fact be a 6 mBar drop over 2 mins which is acceptable providing there is no smell of gas.

Nope, a 9mbar drop over 3 minutes is not the same as a 6mbar drop over 2 minutes.

Why isn't it

 

[spacethegas]

its a bit late but ill have a go at second part.

as pressure drops through leakage, the rate at which it drops will reduce due to the pressure drop.

well makes sense to me.

 

[ChrisR]

Yep, that's what I reckon too.

 

[Bambergaspipe]

Yep, that's what I reckon too.

Dunno why you lot bother, the only ones getting hot under the collar about gas safety is everyone on this site. Corgi don`t bother investigating rogue fitters. I work with plumbers everyday laying gas lines & meters fully unqualified, no-one checks their credentials because no-one cares.Chris is obviously making a few bob by being a know-all but unfortunately it just doesn`t really matter in the real world,Sad as that is.

 

[picasso]

at a guess on the first question , when your testing lpg?

 

[Bambergaspipe]

at a guess on the first question , when your testing lpg?

Not many homes run on that do they?
Unless you`re a soap dodging, social security scrounger, or Gyppo living in a caravan.

 

[nickso]

at a guess on the first question , when your testing lpg?

Not many homes run on that do they?
Unless you`re a soap dodging, social security scrounger, or Gyppo living in a caravan.

or maybe live in the countryside.

 

[Bambergaspipe]

or maybe live in the countryside.

If we can supply it to the third world surely we can afford it to the carrot munchers in Blighty?

Don`t dey hav dat der electrickery in der countryside????