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5 minutes ago, Mike the Boilerman said:

 

Whist I agree with all the points you make in posts 16 and 17, this bit is not really the case I don't think. You are right in particular about the reservoir of high pressure gas in the high pressure hose masking a small leak so it needs to be dissipated. This occurs during the 'let by' part of the LPG tightness test. They are constantly tinkering with the times and pressures but broadly speaking, to do a tightness test with a manometer you follow these steps:

 

Let by test:

 

1) Turn the gas OFF at the bottle, light a burner to dissipate the pressure, remove the test point and attach your previously prepared manometer containing water and a blue dye approved for use with gas.

 

2) SLOWLY and carefully turn the gas on, avoiding a rapid rise in pressure which will shoot all the water out of your manometer.

 

3) Note the pressure which should be 37 mBar for propane. Light a gas ring and reduce the pressure to 10 mBar approx, then turn the gas ring OFF. Note the exact pressure you have. 

 

4) Observe the pressure for one minute to ensure it does not rise.

 

This test is to prove the on/off valve is closing fully. If it doesn't close fully, passing gas will affect the result of the following tightness test:

 

 

Tightness test:

 

1) Open the valve to raise the pressure to 37 mB then close it again. Burn off gas to reduce the pressure this time to 20 mB. 

 

2) Wait five minutes for the system temperature to stabilise and observe the pressure, and record the result.

 

3) Wait a further five minutes. This is the actual tightness test. Note the reading on the manometer and compare it with the result recorded in 2). 

 

There should have been no change in pressure for the system to pass the test. 

 

 

A tightness test carried out at 37mB is pretty pointless really, for the reason Nick points out. 

 

 

Getting back to the bit about the GSUIR governing commercial work, yes it does, if work is being carried out for payment or reward then Registration with the body currently charged with administering the register is mandatory, but in addition it requires non-GSR people working on gas for no payment to be competent, and defines the standards to which ANYONE working on gas should comply to demonstrate their competence. 

 

It is arguable that there might be other ways to work on gas 'competently', but complying with GSIUR is a surefire way to convince the court, should you end up there. 

 

 

Interesting that the tightness test is done at a significantly lower pressure than the operating pressure. 20mB vs 37 mb. Seems odd! I would have thought it better to use the shut off valve in the gas locker (that is after the regulator) rather than the cylinder valve, but perhaps not all boats have them?

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7 hours ago, nicknorman said:

 

The whole thing is a bit of a farce IMO (ie the difference between residential and non residential). I don’t see what difference it makes. We were on the boat permanently for 2 months in the summer, why should that require a lower standard than some other boat where the occupants are there for 2 months but don’t also have a home elsewhere? The law is an ass!

 

Yes precisely, which is why I ignored that aspect of who could fit my gas systems and just did it myself. As long as you read the regs, buy the correct materials (correct pipe and fittings) and install the system as required, clipped correctly, and then get it properly tested the job's a good 'un. My systems have been inspected 4 times by 4 different inspectors all of whom say it's a decent job. One said he hadn't seen a better installation. 

 

I'm not sure why people think installing LPG pipework is some sort of black art that's not to be attempted unless you're a member of the gas safe fraternity. At the end of the day there's really no great mystery to it. It's just plumbing.

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2 minutes ago, blackrose said:

 

Yes precisely, which is why I ignored that aspect of who could fit my gas systems and just did it myself. As long as you read the regs, buy the correct materials (correct pipe and fittings) and install the system as required, clipped correctly, and then get it properly tested the job's a good 'un. My systems have been inspected 4 times by 4 different inspectors all of whom say it's a decent job. One said he hadn't seen a better installation. 

 

I'm not sure why people think installing LPG pipework is some sort of black art that's not to be attempted unless you're a member of the gas safe fraternity. At the end of the day there's really no great mystery to it. It's just plumbing.

Mostly protectionism IMO! And since you boat hasn’t blown up/gassed you and since it has passed several inspections, clearly you were competent to do the work.

 

Anyway, here is the relevant section of the law. Sub Para 1 applies to all, the rest only applies to employers and self-employed, and that is the bit requiring HSE approval (ie GSR)

 

Qualification and supervision

3.—(1) No person shall carry out any work in relation to a gas fitting or gas storage vessel unless he is competent to do so.

(2) The employer of any person carrying out such work for that employer, every other employer and self-employed person who has control to any extent of such work and every employer and self-employed person who has required such work to be carried out at any place of work under his control shall ensure that paragraph (1) above is complied with in relation to such work.

(3) Without prejudice to the generality of paragraphs (1) and (2) above and subject to paragraph (4) below, no employer shall allow any of his employees to carry out any work in relation to a gas fitting or service pipework and no self-employed person shall carry out any such work, unless the employer or self-employed person, as the case may be, is a member of a class of persons approved for the time being by the Health and Safety Executive for the purposes of this paragraph.

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10 minutes ago, rusty69 said:

Please sir.I have a question(s),silly as it may be. Obviously a falling pressure indicates a leak.

 

Is no increase in pressure at all permissible?

Would the ambient temperature if increasing not affect the reading?

 

Stop asking difficult questions....

 

Yes a rise in the result indicates the sun came out, or the let-by test was invalid and you should start all over again!

 

 

 

9 minutes ago, blackrose said:

At the end of the day there's really no great mystery to it. It's just plumbing.

 

Except that it isn't just plumbing.

 

You have totally overlooked 50% of the skill/training involved in gas work, which is mistake typical of people who are not GSR.

 

 

 

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16 minutes ago, nicknorman said:

The whole thing is a bit of a farce IMO (ie the difference between residential and non residential). I don’t see what difference it makes. We were on the boat permanently for 2 months in the summer, why should that require a lower standard than some other boat where the occupants are there for 2 months but don’t also have a home elsewhere? The law is an ass!

I have had a quick Google (I know), and it looks to me as though the regulations apply to boats in which the owner/user lives for most of the time.  If this is correct, then it is not a question of no-other-abode liveaboard (or not).

 

Someone may well know better than me - but over what period is "most of the time" measured?  Maybe its a year, which seems reasonable  But if one takes Nick's summer,  he may well live on his boat most of the time.   On the other hand you could take a much longer period of several years and come to a different conclusion even if you lived aboard for one calendar year.

 

 

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13 minutes ago, blackrose said:

.............. then get it properly tested the job's a good 'un.

I think that is the 'secret'.

 

Plumb it in yourself and get it properly checked.

 

The difference between plumbing for gas and for water is potentially getting it wrong with gas can lead to death.

 

You can see water leaking and collecting in the bottom of the boat, you cannot see gas and until it goes 'bang' you may have no idea it is there.

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On the subject of competence I was having a look at the gas central heating installation in my rental flat (currently between tenants) - flat was built in 2014. There is a 35kw Combi boiler, which is a big boiler for a small well insulated flat, but never mind that is for the hot water, and it modulates down well or should do! The thermostat in the hall is a fancy one that communicates and is powered over eBus to the boiler. It is thus not just on or off  it sends data about the difference between set and actual temperature etc. Except that it has always seemed rather “on or off” and the facility to change the tap water temperature has never worked. There are only 2 wires coming from the thermostat, and due to the way eBus works, the polarity is unimportant. At the other end there are 3 terminals. The installation manual clearly shows the thermostat wires connected between 0v and eBus, but in fact mine was connected between third terminal (24v) and eBus. So given the task of connecting 2 wires in any order, to the right 2 out of 3 terminals, the installer managed to get it wrong. Is that competent?

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9 minutes ago, Tacet said:

I have had a quick Google (I know), and it looks to me as though the regulations apply to boats in which the owner/user lives for most of the time.  If this is correct, then it is not a question of no-other-abode liveaboard (or not).

 

Someone may well know better than me - but over what period is "most of the time" measured?  Maybe its a year, which seems reasonable  But if one takes Nick's summer,  he may well live on his boat most of the time.   On the other hand you could take a much longer period of several years and come to a different conclusion even if you lived aboard for one calendar year.

 

 

It is a residential boat if it is your sole, or main, residence.

 

It could be argued that at 6 months and 1 day on board it becomes you main residence.

 

However :

 

CODNER v WILTSHIRE VALUATION AND COMMUNITY CHARGE TRIBUNAL (1994)

The High Court confirmed the principle that time was not the only factor to be considered in determining sole or main residence.

 

The courts use the following as indicators of main residence :

 

Personal Ties
 

  • At which residence you are registered with a doctor / dentist
  • Where the majority of your possessions are kept
  • Where you return to during periods of leave or at the end of employment
  • Your long-term intentions
  • Are you already regarded as mainly resident elsewhere for council tax purposes
  • Where you are registered to vote
  • Membership of clubs and other social activities  
  • Where you receive post
  • Which property you regard as your main residence
  • How you split your time between your residences


Family Ties
 

  • At which residence your partner / dependants live
  • From which residence your children attend school
  • At which residence you spend time with your family    

 

Edited by Alan de Enfield
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8 minutes ago, Tacet said:

I have had a quick Google (I know), and it looks to me as though the regulations apply to boats in which the owner/user lives for most of the time.  If this is correct, then it is not a question of no-other-abode liveaboard (or not).

 

Someone may well know better than me - but over what period is "most of the time" measured?  Maybe its a year, which seems reasonable  But if one takes Nick's summer,  he may well live on his boat most of the time.   On the other hand you could take a much longer period of several years and come to a different conclusion even if you lived aboard for one calendar year.

 

 

This is what the exemption to the law actually says:

 

5) Nothing in these Regulations shall apply in relation to the supply of gas to, or anything done in respect of a gas fitting on—

...

c)a vessel not requiring a national or international load line certificate except when such vessel is—

(i)hired out in the course of a business;

(ii)made available to members of the public in the course of a business carried out from that vessel; or

(iii)used primarily for domestic or residential purposes;

 

So it is (iii) that is relevant. But what does it mean? Well the industry has decided that it means live aboard vs not live aboard. Personally I’d say that all leisure Narrowboats are used primarily for domestic or residential purposes even if only for 2 weeks a year. The rest of the time (when the owners are not aboard) the boat is not used at all. What else are they used for? 

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7 hours ago, Mike the Boilerman said:

 

Except that it isn't just plumbing.

 

You have totally overlooked 50% of the skill/training involved in gas work, which is mistake typical of people who are not GSR.

 

 

We've had this exact discussion before Mike. I appreciate that gas safe registered tradespeople want & need to protect their positions and don't want non-registered people doing the work themselves, so like most tradespeople they try to shroud their subject in complexity and mystery. However, for competent people it is just plumbing - albeit plumbing that incorporates some other elements, but none that are beyond the wit of most reasonably intelligent DIYers. If that were not the case how did I manage to do such a good job? I had absolutely no prior experience. Did I just get lucky or is the truth that it's not really that complicated?

 

Edit: I'm not trying to say that I can fix a boiler or do some of the other things that you can do, but I can and have installed two LPG systems to a good standard.

Edited by blackrose
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3 hours ago, Jo_ said:

I did the bit below a couple of months ago in our Newsletter. It was done with a lot of input and checking!

Boat Safety Scheme (BSS)

The Gas Aspect - Examiners, Bubble Testers and Manometers

A BSS Examination is a safety check every four years to ensure your boat is being kept in a condition that complies with the BSS requirements (and be aware that, in the intervening period, your boat  must not have any non-compliant changes to any of its systems which are subject to a BSS check). You can find an Examiner from the BSS website - www.boatsafetyscheme.org – which lists Examiners by area and gives full details of the scheme..

HOWEVER, a key element of the BSS Examination - the Gas check (7.12.2) - is critical as to whether your BSS Examiner will be able to issue a ‘pass’ confirmation for your boat. Graham Watts, BSS Support Executive, has been the lead on what follows.

1.       If you are a leisure user (i.e. non-residential and your boat is non-commercial [not a hire boat, not a shop etc.]) any BSS Examiner can complete the safety checks and issue a ‘pass’ because they can check for gas leaks (check 7.12.2) using a manometer.

2.       If you are a residential boater then if your BSS Examiner is not also Gas Safe (LPG boats-competent) registered, the Examiner can only complete check 7.12.2 (and therefore issue the ‘pass’) by either

          a.       observing the tightness test conducted by an attending GSR engineer

          b.       undertaking a gas tightness test using a bubble tester where correctly fitted and correctly located

Less than 30% of BSS Examiners are also GSR so check for an in-date ID card if necessary.

In terms of the (b) option, a bubble tester must be fitted by a GSR engineer** and if the total kW rating of appliances running through the system is greater than 12kW (as in most widebeams), the bubble tester cannot be fitted in-line but needs to be on a by-pass. This can be awkward in the locker and, to complicate matters, they are designed to fit to metric pipework. To add to this, a big part of the GasSafe gas test is the gas pressures of the system which the bubble tester doesn’t show.

Two final points: The BSS does not require you to have a bubble-tester fitted. And, particularly important, if you are a residential boater, consider the sense in having an annual routine gas check.

**Boats used for residential purposes as well as hire boats and floating businesses (such as cafés or shops) all fall within scope of the Gas Safety [Installation and Use] Regulations (GSIUR) and as such any LPG 'work' must be undertaken by Gas Safe registered installers.

Alde bubble testers are available adapted to imperial (which is difficult to do yourself). I got mine from Socal. I think they might do other sizes to order? I thought I bought 5/8ths but I might be wrong.

https://www.socal.co.uk/search/bubble

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30 minutes ago, system 4-50 said:

Alde bubble testers are available adapted to imperial (which is difficult to do yourself). I got mine from Socal. I think they might do other sizes to order? I thought I bought 5/8ths but I might be wrong.

https://www.socal.co.uk/search/bubble

It's disappointing tough that these days there is a £20 mark up for the conversion to Imperial!

I always hoped to be able to buy one ready fitted with 1/2" fittings, but maybe it is that the 12KW maximum rating means that it can't cope properly with the kinds of maximum flow rate that using a 1/2" main delivery pipe implies?

 

So, (still seeking the definitive answer!), if you can have theoretical maximum in excess of 12KW, should these not be fitted directly inline?

 

Also, (supplementary question) if you do fit one with a loop that allows it to be bypassed, is it still accepted by the BSS, given that this  will result in some low pressure joints (albeit in the gas locker), that it can't actually test as gas tight?

Does anybody actually manufacture a bubble tester suitable for use on boat systems that is rated as good for more than 12KW?

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24 minutes ago, bizzard said:

An ordinary little test point for a manometer is only a fraction of the price of a bubble tester which are nearly £50 plus installation, and get yourself a BSS inspector that is Boat gas safe registered.

And that of course only applies to liveaboards.

 

A non gas-safe registered BSS examiner can use a manometer on a 'leisure' boat.

 

Maybe liveaboard lives are more valuable than leisure boaters.

 

Ridiculous isn't it !!!

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2 hours ago, Mike the Boilerman said:

 

Whist I agree with all the points you make in posts 16 and 17, this bit is not really the case I don't think. You are right in particular about the reservoir of high pressure gas in the high pressure hose masking a small leak so it needs to be dissipated. This occurs during the 'let by' part of the LPG tightness test. They are constantly tinkering with the times and pressures but broadly speaking, to do a tightness test with a manometer you follow these steps:

 

Let by test:

 

1) Turn the gas OFF at the bottle, light a burner to dissipate the pressure, remove the test point and attach your previously prepared manometer containing water and a blue dye approved for use with gas.

 

2) SLOWLY and carefully turn the gas on, avoiding a rapid rise in pressure which will shoot all the water out of your manometer.

 

3) Note the pressure which should be 37 mBar for propane. Light a gas ring and reduce the pressure to 10 mBar approx, then turn the gas ring OFF. Note the exact pressure you have. 

 

4) Observe the pressure for one minute to ensure it does not rise.

 

This test is to prove the on/off valve is closing fully. If it doesn't close fully, passing gas will affect the result of the following tightness test:

 

 

Tightness test:

 

1) Open the valve to raise the pressure to 37 mB then close it again. Burn off gas to reduce the pressure this time to 20 mB. 

 

2) Wait five minutes for the system temperature to stabilise and observe the pressure, and record the result.

 

3) Wait a further five minutes. This is the actual tightness test. Note the reading on the manometer and compare it with the result recorded in 2). 

 

There should have been no change in pressure for the system to pass the test. 

 

 

A tightness test carried out at 37mB is pretty pointless really, for the reason Nick points out. 

 

 

Getting back to the bit about the GSUIR governing commercial work, yes it does, if work is being carried out for payment or reward then Registration with the body currently charged with administering the register is mandatory, but in addition it requires non-GSR people working on gas for no payment to be competent, and defines the standards to which ANYONE working on gas should comply to demonstrate their competence. 

 

It is arguable that there might be other ways to work on gas 'competently', but complying with GSIUR is a surefire way to convince the court, should you end up there. 

 

 

 

 

Yes that is more or less what I actually used to do. I clearly missed out some of the details, but it is quite a while since I did a test.  I no longer have a copy of the various stages, which were pasted onto the back of the manometer, which I disposed of after I sold the boat.

 

 

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12 hours ago, alan_fincher said:

But you then don't know you have a leak proof system, as it may be leaking due  to a cock up you made whilst replacing the plug on the test point.  You would need a bubble tester to be confident you had got the final part right! ?

Really are you that cack handed? I am not. Anyway there are two tests which can be done to test whether a test point is leaking, there is the well tried washing up liquid test. or an old plumbers test - a lit match. I have seen both being deployed by a gas fitter.

 

 

Edited by David Schweizer
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2 hours ago, alan_fincher said:

 

Also, (supplementary question) if you do fit one with a loop that allows it to be bypassed, is it still accepted by the BSS, given that this  will result in some low pressure joints (albeit in the gas locker), that it can't actually test as gas tight?

 

But a bubble tester fitted without a bypass will still have low pressure joints (between the regulator and the bubble tester) which are not tested for gas tightness.

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8 minutes ago, David Mack said:

 

But a bubble tester fitted without a bypass will still have low pressure joints (between the regulator and the bubble tester) which are not tested for gas tightness.

Yes, but not as many.

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16 minutes ago, David Mack said:

 

But a bubble tester fitted without a bypass will still have low pressure joints (between the regulator and the bubble tester) which are not tested for gas tightness.

Yes but they're in the gas locker, so it doesn't matter.

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3 hours ago, alan_fincher said:

It's disappointing tough that these days there is a £20 mark up for the conversion to Imperial!

I always hoped to be able to buy one ready fitted with 1/2" fittings, but maybe it is that the 12KW maximum rating means that it can't cope properly with the kinds of maximum flow rate that using a 1/2" main delivery pipe implies?

 

So, (still seeking the definitive answer!), if you can have theoretical maximum in excess of 12KW, should these not be fitted directly inline?

 

Also, (supplementary question) if you do fit one with a loop that allows it to be bypassed, is it still accepted by the BSS, given that this  will result in some low pressure joints (albeit in the gas locker), that it can't actually test as gas tight?

Does anybody actually manufacture a bubble tester suitable for use on boat systems that is rated as good for more than 12KW?

Appendix D in the BSS private boat check list specifically recognises the possible fitting of a bypass loop.  It simply tells you to ensure gas passes through the bubble tester during the test.  As to the untested joints, the BSS requires the examiner to use leak detection fluid.  So all is ok.

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