let by test

[namsag]

Bell824 my apologies your humour was lost on me, but have seen just as bad answers in the CC.





Answers on a postcard

What other simple thing on a meter could have the gauge rising up to the 24mbar on a letby test but no letby present
Transco get called to it far too much

 

[expertgasman]

Ryman, assuming this is no wind up, did you test the ECV after the fail?

 

[DeltaT2]

It's another wind-up. You guys from the combustion chamber pot bite like chub!! Get over yourselves FFS!!

 

[Agile]

Delta 2, go back into your Combustion Chamber where you belong!

 

[Agile]

What other simple thing on a meter could have the gauge rising up to the 24mbar on a letby test but no letby present

If you are thinking of what I am thinking, then that would not happen if you did the letby test as prescribed by raising the pressure from zero to 10 mB.

All this should be in the CC though.

Tony

 

[namsag]

Yes it does happen and what other proper way of doing a letby is there other than allowing pressure to rise from zero.

Give me a one word answer that covers why you think it happens .
Diyers wont have a clue .


If delta does not have a current gas qualification as has been said in the CC why should he be allowed in .

No offense delta

 

[DeltaT2]

Yes it does happen and what other proper way of doing a letby is there other than allowing pressure to rise from zero.

Give me a one word answer that covers why you think it happens .
Diyers wont have a clue .


If delta does not have a current gas qualification as has been said in the CC why should he be allowed in .

No offense delta

I'm not offended mate...........

Oh, but I do have my ACS mate, but I was fairly excluded from the chamber pot some time ago - so that's life.
I did apply for re-entry though, but alas still no joy.

 

[kirkgas]

when carrying out a let by test, the pressure stays at 10mbar for the first min but after a short time pressure risses to 24mbar. is this a let by fail?

i would suggest this scenario is impossible, by definition a let by test is to prove the valve is open or shut, if you dont touch it cant change so if it is 10mb and not completely shut then it must rise steadily (with a speed determined by the size of the crud on the valve seating) it cannot jump from 10 to 24, even if the regulator burst at the exact moment you were doing the test and allowed a high pressure of gas to enter the system the valve was either shutting or not

 

[expertgasman]

Yes it does happen and what other proper way of doing a letby is there other than allowing pressure to rise from zero.

Not "proper", but if full pressure is allowed through, governor locks off, then ECV off, then allow gas out via tube DOWN to 10mb, the governor won't unlock, then small amount of gas passing MAY build up pre governor without lifting seating, then result in a surge , once pre governor pressure has built up sufficiently to unlock

I think.

 

[namsag]

Nope , meter with nipple more or less completely blocked with grease so it doesnt let proper pressure through to gauge so as you slowly let the pressure on gauge rise to ten then shut valve off the actuall pressure is far higher behind it .
So with gas now off the pressure eventually will equalise and makes the gauge look like it is rising on letby .
Transco get called out weekly to this and in reality it should be obvious straight away.


Sorry Delta one of the glasgow guys in CC said you no longer had rocket science sorry i mean gas

 

[doitall]

I have it on good authority he has namsag

 

[DeltaT2]

I have it on good authority he has namsag

................

Aye I do, along with my full ACOPs, old manky U gauge you can hardly read, fag lighter for finding the gas leaks & Firerite 'FGA' kit!!

 

[Agile]

Yes it does happen and what other proper way of doing a letby is there other than allowing pressure to rise from zero.

It was the blocked nipple I had in mind.

But if the system pressure is allowed to vent for long enough ( or with a cooker ) and gives a stable zero pressure it will become obvious the nipple is blocked when you try to set it to 10 mB.

I am sure there are a lot of guys who reduce the pressure from 20 mB down to 10 mB when they do a letby.

Tony

 

[centrica1eng]

governor lock up? ECV letting by, is it a domestic dwelling? are you even gas safe registerd?

 

[ryman1]

governor lock up? ECV letting by, is it a domestic dwelling? are you even gas safe registerd?

no im training towards my gas safe at mo hense my stupidity!! i was given the scenario by my trainer, who is gas safe.

was just unsure because the pressure stayed within the perceptible limits for the 1 min stated, i thaught there could be temp change or something that may affect longer tests times?

silly me!!