LPG leak ?

[Rob-M]

16 minutes ago, Boater Sam said:

To be absolutely sure, do a manometer drop test on the test nipple,  that cannot tell lies . The old ways are best. What are you using as test fluid?

Never liked these new fangled bubble blowers, I refuse to have one, not full time on the boat.

I had a persistent minute leak for 2 years, finally traced it to the shut off valve for the cooker, it must of had a leak from new. Regreasing it cured it.

We had troubles with cooker cleaning firms washing the grease out of the taps with solvent when they stripped cleaned.

A manometer will only tell you there is a leak, still need to find where the leak is.

 

When we had a new cooker connected the gas fitter did a test and identified there was a leak. He then used a gas detector to test around the new connection and worked back from there until identifying the joint that was leaking.

[Boater Sam]

35 minutes ago, Mike the Boilerman said:

 

How little you knows about gas!!

Really?

I was a Corgi committee senior member for many years, inspecting and reporting on work from folk like yourself.

Perhaps you were being humorous, Otherwise you would seem to be very insulting Mike and surely that is not your style?

[MtB]

Just now, Boater Sam said:

Really?

I was a Corgi committee senior member for many years, inspecting and reporting on work from folk like yourself.

Perhaps you were being humorous, Otherwise you would seem to be very insulting Mike and surely that is not your style?

 

Then you will know about the circumstances when a manometer lies, won't you.

 

 

Your comment is all the more surprising given your experience.

 

 

 

[bizzard]

The  H M the Queen is also a Corgi expert.  

[WotEver]

2 hours ago, W+T said:

Has to be the tester at fault ??? 

Absolutely not. It is accurately indicating that all three circuits have a small leak. A manometer would do no more or less. 

 

A bubble in the bubble tester demonstrates that gas is passing through it. If gas is passing then there is a flow. If everything is turned off then that flow has to be caused by a leak. As you’ve checked all the joints I’d be suspicious of the valves on the individual units. 

[Jess--]

No gas expert here but had an odd one a few years ago with a gas stove on calor bottles

 

when a burner was first opened it would flare up (to about 4 times its proper size) and then die down and work normally, a second burner would work perfectly, it would only do it if there had been no burners on / gas used for about 4 hours and it would do it on whichever burner was switched on first.

 

turned out to be a faulty regulator that never fully shut off when it reached pressure on the low pressure side and kept slowly increasing the pressure on the gas system until it was close to the pressure in the bottle.

 

the same fault could give the result you are seeing where the more pipework you have connected / switched on the more space it has to pressurise so you see more bubbles

[W+T]

21 hours ago, Mike the Boilerman said:

Do you have isolating valves at the appliance end of each of the three gas lines? If so, do you still have the leaks with these turned off? If not, fit them - it helps with leak tracing!

 

There is no short cut to finding the leaks I'm afraid. Leak detection fluid and gas sniffer are the main tools to use. 

 

Good luck with it. LPG leaks can be hard to find, but you KNOW they are there for the finding. 

 

 

Ok i have give up on detector spray as nothing is showing. So now i am going to get a Sniffer. 

 

Any type or make to go for ?

 

Looking at this one 

 

https://www.screwfix.com/p/tpi-725l-pocket-combustible-gas-detector/6050k

Edited May 19, 2019 by W+T

[bizzard]

8 minutes ago, W+T said:

 

 

Ok i have give up on detector spray as nothing is showing. So now i am going to get a Sniffer. 

 

Any type or make to go for ?

 

Looking at this one 

 

https://www.screwfix.com/p/tpi-725l-pocket-combustible-gas-detector/6050k

You need to dabble the liquid around the joints with a little paint brush, this disperses the missleading fizz from the spray

 

Pocket combustible sounds dangerous.

Edited May 19, 2019 by bizzard

[MtB]

9 minutes ago, W+T said:

 

 

Ok i have give up on detector spray as nothing is showing. So now i am going to get a Sniffer. 

 

Any type or make to go for ?

 

Looking at this one 

 

https://www.screwfix.com/p/tpi-725l-pocket-combustible-gas-detector/6050k

 

Sadly that one is pretty useless. I bought one and threw it away. The ones with an air pump inside that draw in a continuous flow of air and pass it over the sensor inside are far superior. That one relies on whiffs of gas wafting into the passive sensor.  

 

But firstly, try your Mark One nose. Get it right up close to every joint and have a good sniff. If you get even the slightest hint of gas, that will be a leak. Then give it close attention with the leak detection fluid. It's easy to miss tiny leaks like you have with the LDF. 

 

 

[W+T]

6 minutes ago, bizzard said:

You need to dabble the liquid around the joints with a little paint brush, this disperses the missleading fizz from the spray

 

Pocket combustible sounds dangerous.

I do so and sit for minutes at a time waiting to see bubbles which dont appear. . 

 

[Ray T]

Do you know an Openreach Engineer? See if you can borrow a gas detector.

From my experiences with the old IG 5, the ones used by OR (or at it was in my day BT.)  are very sensitive.

[MtB]

just been googling for the type of sniffer i mean but there don't seem to be any, sadly. 

 

Maybe the passive ones have got better....

 

 

[bizzard]

20 minutes ago, W+T said:

I do so and sit for minutes at a time waiting to see bubbles which dont appear. . 

 

You probably haven't got any leaks if you've been that vigilant with the fluid. And its strange that you say there weren't any leaks at first and now there are. Mind you, you did say in post 1 that you found some joints too tight, did you just slacken them a bit, BAD, or renew the olives and re-tighten them? Personally I'm not a fan of bubble testers.

 

  Krufts Corgi expert. 

[Alan de Enfield]

4 minutes ago, bizzard said:

Krufts Corgi expert. 

 

 

[Murflynn]

2 hours ago, Jess-- said:

No gas expert here but had an odd one a few years ago with a gas stove on calor bottles

 

when a burner was first opened it would flare up (to about 4 times its proper size) and then die down and work normally, a second burner would work perfectly, it would only do it if there had been no burners on / gas used for about 4 hours and it would do it on whichever burner was switched on first.

 

turned out to be a faulty regulator that never fully shut off when it reached pressure on the low pressure side and kept slowly increasing the pressure on the gas system until it was close to the pressure in the bottle.

 

the same fault could give the result you are seeing where the more pipework you have connected / switched on the more space it has to pressurise so you see more bubbles

that sounds scary, but could certainly explain what may be happening.  

 

so the regulator may be at fault after all.......  an easy fix even if just to eliminate this possibility.

[Guest]

I fitted a bubble tester a few years ago now and it nearly drove me mad in the first winter. During a very cold snap I changed a gas bottle and did a routine bubble test to find, horror of horrors, bubbles showing. Very small and occasional, but there were definitely bubbles. I tested all joints with leak detector, did various tests with various valves open and closed, but still the odd bubble. Out came the manometer (never thought I would use it again) and it showed absolutely no drop during the recognised test. procedure. I have a good sniffer (makes up for my hearing and eyesight) which could detect no leaks. Some time later when the weather was much more mild, and no stove lit in the boat the "leak according to the bubble tester" had completely disappeared. I am no expert on gas or anything else, but remain convinced that the "leak" was something to do with the fact that it was -5 deg on the outside pipework, and probably about +25 inside the cabin. I am open to other suggestions, but never saw the "leak" again!

[W+T]

8 minutes ago, bizzard said:

You probably haven't got any leaks if you've been that vigilant with the fluid. And its strange that you say there weren't any leaks at first and now there are. Mind you, you did say in post 1 that you found some joints too tight, did you just slacken them a bit, BAD, or renew the olives and re-tighten them? Personally I'm not a fan of bubble testers.

 

  Krufts Corgi expert. 

The ones that were tight when i tried to nip them up i replaced the olives. 

[Guest]

2 minutes ago, Murflynn said:

that sounds scary, but could certainly explain what may be happening.  

 

so the regulator may be at fault after all.......  an easy fix even if just to eliminate this possibility.

I think it is recommended that they are changed at given intervals? (can't remember the interval now.)

10 minutes ago, bizzard said:

You probably haven't got any leaks if you've been that vigilant with the fluid. And its strange that you say there weren't any leaks at first and now there are. Mind you, you did say in post 1 that you found some joints too tight, did you just slacken them a bit, BAD, or renew the olives and re-tighten them? Personally I'm not a fan of bubble testers.

 

  Krufts Corgi expert. 

I am not 100% convinced after my experience.

[bizzard]

I have a Gaslow regulator with a gauge on it. This works very well as far as rough checking for leaks are concerned and is surprisingly fairly accurate comparing with a manometer, but mainly it does give an indication of a leak. With appliance isolation va;lves open and appliance taps off and turn the gas bottles big main knob off and watch the gauge needle. If it remains in the green for ever, no leaks, If it drops passing through yellow to red and depending on the speed of the drop denotes the severity of the leak.  A good rough check.

[W+T]

I am going to get a 3/8 BSP  test point for the end of the taps so then there is another way to test for leaks. Just trying to find one now as all seem to be 1/8 BSP.

 

 

[bizzard]

5 minutes ago, W+T said:

I am going to get a 3/8 BSP  test point for the end of the taps so then there is another way to test for leaks. Just trying to find one now as all seem to be 1/8 BSP.

 

 

Mine is on a T piece for 3/8'' pipe.

[Alan de Enfield]

14 minutes ago, W+T said:

I am going to get a 3/8 BSP  test point for the end of the taps so then there is another way to test for leaks. Just trying to find one now as all seem to be 1/8 BSP.

 

 

Just but 3 of them.

[W+T]

38 minutes ago, Alan de Enfield said:

Just but 3 of them.

One of these test points.

 

Top right 

 

[croftie]

ave you tried turning on the tap (one of the 3 isolater ones in your pic) to the hob and lighting all the rings for a couple of minutes to get rid of any "air" in the system. then doing a bubble test on that circuit?

[W+T]

8 minutes ago, croftie said:

ave you tried turning on the tap (one of the 3 isolater ones in your pic) to the hob and lighting all the rings for a couple of minutes to get rid of any "air" in the system. then doing a bubble test on that circuit?

Yep, dont thin there isnt anything i havnt done. Its one of the things you do when testing the system. Run all appliances then let them shut down before you do the test.