Gas going out

[Milly161]

hi as the heading says, gas ignites on the hob and the heating but after a few mins it goes out and then I have to go back outside and re press the valves in the gas cupboard

We are away at the moment on our first proper holiday

Any help will be greatly appreciated

Thanks

(Autocruise augusta)

[Derek Uzzell]

I’ve looked through your earlier forum postings but (although this was asked several times) I cannot find any indication of when your Autocruise Augusta was manufactured. This information is often important when an enquiry is made, which is why there is a ‘IDENTIFYING YOUR MOTORHOME’ entry at the top of this forum.

 

https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/IDENTIFYING-YOUR-MOTORHOME/54713/

 

However, based on your comment "I have to go back outside and re press the valves in the gas cupboard” I’m guessing that your motorhome is fitted with a Truma “SecuMotion/Drive-Safe” system that has a regulator and gas hose(s) fitted with green push-buttons as shown in the 1st image attached below and operated as described in the 2nd image.

 

The sort of problem you are experiencing was described in this 2016 discussion, but was never resolved satisfactorily.

 

https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Truma-secumotion/42281/

 

But (and again it’s a guess) I suspect that your problem lies with the SecuMotion regulator and - if that’s the case - the regulator will need to be replaced.

 

As you’ll see from this link, SecuMotion regulator problems have been quite commonplace.

 

https://tinyurl.com/y43xe97b

 

There are some basic checks that could be made, but, as this is your first motorhome, you only obtained it in October 2019 and the fault is gas-related (hence potentially dangerous) you’d be wise to get the problem looked at professionally.

[witzend]

Milly161 - 2020-08-02 10:28 PM

We are away at the moment on our first proper holiday Any help will be greatly appreciated Thanks

(Autocruise augusta)

 

Some times we over look the obvious is there gas in the bottle are you opening the valve enough, But the regulators are a known source of trouble

[Milly161]

Hi thanks for the replies. Yes the common consensus is its the regulator but unfortunately no one round here has one in stock. But luckily we have a cadac with a separate bottle and a large george foreman grill so should be ok till we get home

[pepe63xnotuse]

If you have the elbow room within the locker, and access to a "camping/caravan shop" , could you not just remove the existing reg' & hose and use a bottle mounted reg', with some low pressure hose,jubilee clipped to the rigid pipework...?

[Milly161]

Hadn't thought of that till you put that , will have a look for one tomorrow

[graham]

We have had one of these on an Autocruise Starfire and it is absolutely essential that you press and release very slowly allowing a bit more than the specified time.

[Paul-]

original regulator works at 30mb and I would think that appliances will have the corresponding jets, whats the bottle regulator work at 37mb or 28?

[Derek Uzzell]

Although, historically in the UK, a 28mbar ‘on-bottle’ regulator was used with butane canisters or a 37mbar regulator for propane canisters, it is possible to obtain on-bottle 30mbar regulators. (My 2005 Hobby motorhome came with one.)

 

It needs emphasising that, although pepe63’s suggestion is viable in principle, how practicable it would be to implement on Milly’s Autocruise Augusta would depend on what that motorhome's gas system comprises.

 

I vividly recall a forum discussion where someone was advised in ultra-fine detail how a French gas-bottle might be fitted to his UK motorhome. The procedure was simple enough in principle, but the follow-up was that, when in France, a potentially lethal balls-up was made TWICE by well-meaning but incompetent amateurs carrying out the task.

 

Assuming that the present problem is down to the regulator, although the simplest ‘cure’ should be to replace the current regulator on an exact like-for-like basis (NB: Truma Secumotion/Drive-safe regulators come in two versions - for 10mm metal pipework or for 8mm metal pipework) a different regulator could be fitted instead. For example, a Clesse regulator (10mm or 8mm pipework) of the type shown here

 

https://www.gaslowdirect.com/Gaslow-Clesse-30mbar-Regulator

 

Just to repeat the advice I gave Milly in my first posting above

 

"There are some basic checks that could be made, but, as this is your first motorhome, you only obtained it in October 2019 and the fault is gas-related (hence potentially dangerous) you’d be wise to get the problem looked at professionally.

 

If Milly lacks the technical expertise to address this problem temporarily (and pepe63’s advice must be considered a temporary ‘fix’) then whoever sorts this fault out better know what they are doing...

 

[pepe63xnotuse]

Derek Uzzell - 2020-08-04 8:50 AM

 

Just to repeat the advice I gave Milly in my first posting above

 

"There are some basic checks that could be made, but, as this is your first motorhome, you only obtained it in October 2019 and the fault is gas-related (hence potentially dangerous) you’d be wise to get the problem looked at professionally.

 

If Milly lacks the technical expertise to address this problem temporarily (and pepe63’s advice must be considered a temporary ‘fix’) then whoever sorts this fault out better know what they are doing...

 

Yes,as the OP was away on their holidays, the option I put forward was only meant as a temporary fix (and to be carried out by someone who knew what they were doing).

 

But as you say, as it is gas related,and the van is relatively new to the OP, best just get it looked at properly, when they get home.

It sounds like, that as far as cooking goes, they have the kit to get by without needing to use the van's gas anyway.

:-D

[weldted]

Oil contamination of security motion regulators was a common thread. You may be able to ease it a bit by pouring a kettle of boiling water over the regulator. We have an inline filter between the tank and regulator. It is also helpful if the regulator is mounted higher than the bottles.

[Brian Kirby]

Milly161 - 2020-08-02 10:28 PM

hi as the heading says, gas ignites on the hob and the heating but after a few mins it goes out and then I have to go back outside and re press the valves in the gas cupboard

We are away at the moment on our first proper holiday

Any help will be greatly appreciated

Thanks

(Autocruise augusta)

All as above, especially checking that you have the gas fully on at the cylinder :-D, but…………. If the "valves" in the gas locker are those on the high pressure "pigtails" adjacent to the cylinder connection/s, I have only experienced this when the valves "think" they've "seen" a downstream leak. They are rupture protection valves (RPVs) and are designed primarily to isolate the gas supply if the high pressure hose ruptures, so as to prevent a serious gas leak between the cylinder and the regulator. I can't quite see, therefore, why a defective regulator should cause those valves to close (unless the regulator itself is the source of the leak).

 

Once the gas system has been fully pressurised and the RPVs have been opened, they should remain open (the gas pressure maintains them in the open position) - unless there is a leak somewhere that allows the system pressure to drop. That possibility is what is bugging me.

 

Do you habitually turn off the gas at the cylinder/s when not using gas? If you do, and there is even a slight a leak, system pressure will drop until the RPV shuts. Then, with gas off at the cylinder, all that is available to the appliances is the gas left in the system, which will remain under low pressure for some time. When an appliance is then turned on it will light momentarily on the residual gas pressure, but shortly fail. How long it will remain alight depends on the length, and diameters, of the gas pipes in your system. That is what you seem to be describing.

 

My first suggestion would be to check the pig-tail connections at both ends, with the gas turned fully on, using soapy water to check for a leak. If no leak is revealed then, I think the safest course of action would be to get the van into a motorhome/caravan dealership as soon as possible (or locate a mobile service), and get them to do a gas leakage test on your system.

[witzend]

Milly161 - 2020-08-03 2:38 PM

But luckily we have a cadac with a separate bottle and a large george foreman grill so should be ok till we get home

 

What sort of regulator are you using for these could you use it as a temporary replacement

[Keithl]

Brian,

 

I have to disagree with your diagnosis of the regulator not being at fault. If the regulator was failing and not supplying as much gas as was being consumed then this would be the same scenario as shutting the cylinder valve and allowing the MH to stand. The operating instruction extract posted above clearly states the RPV may switch off after a period of non use so the same would happen with a failing regulator, low pressure causes the valve to switch off.

 

Keith.

[Paul-]

If we had opted for the 30mb bottle mounted regulator back in 2003 we wouldn't have had bulkhead regulators and their associated problems.

Admitted low pressure gas still extracts the plasticisers for from the rubber pipework but to a far lesser extent.

 

Progress eh *-)

[Derek Uzzell]

Truma’s SecuMotion/Drive-Safe system has two protective elements initiated by 1) a rupture protection button on the high-pressure gas-hose that guards against a major leak occurring between the gas-bottle and the regulator and 2) a gas-flow monitor button integrated into the regulator and guarding against a gas leak ‘downstream’ of the regulator. To be effective the maximum ‘normal usage’ gas-flow needed to be matched to the regulator, resulting in Truma marketing SecuMotion regulators with different gas-flow values.

 

When this type of Truma regulator fails, it usually fails completely, but what seems to be happening in Milly’s case sounds odd. As witzend touched on earlier, I’d first want to check that the gas-bottle is delivering gas at full pressure to the regulator as (obviously) if that’s not happening, the regulator may well not be the culprit.

 

It’s likely that anyone here familiar with motorhome gas systems could accurately and rapidly identify the cause of Milly’s problem if they could inspect the motorhome’s system and see what’s going on. However, it’s not known if Milly’s motorhome actually has the SecuMotion system (I provided images in my 1st posting above that should have allowed Milly to confirm if the Autocruise Augusta has SecuMotion) so there’s been a lot of subsequent guesswork that may be irrelevant.

 

It appears that Milly has had someone with some expertise look at the problem ("Yes the common consensus is its the regulator..”) so I’m doubtful that attempting a remote diagnosis and ‘fix’ is going to be worthwhile.

 

(The reason that SecuMotion and alternative ’safety’ regulators were introduced was to allow gas-fuelled heaters to be operated legally Europe-wide in a moving vehicle. The 30mbar compromise gas-pressure could be met by a simple on-bottle regulator, but the moving-vehicle regulatory requirements could not.)

[weldted]

From our then new van in 2008, next new in 2012, both had secure motion regulators had regular problems and several replacements, fitted an inline filter between tank and regulator with replaceable cartridge not had one fail since. When bought our current one new in 2019, when having an underslung tank fitted specified an inline filter to be fitted. 11 months on no problems, although not much use during lockdown heater has run a lot over the winter.

[Brian Kirby]

Keithl - 2020-08-04 5:33 PM

Brian,

I have to disagree with your diagnosis of the regulator not being at fault. If the regulator was failing and not supplying as much gas as was being consumed then this would be the same scenario as shutting the cylinder valve and allowing the MH to stand. The operating instruction extract posted above clearly states the RPV may switch off after a period of non use so the same would happen with a failing regulator, low pressure causes the valve to switch off.

Keith.

I had to think about that, Keith! :-) BTW, I hadn't assumed that the regulator was not at fault, it was just that I couldn't understand why the RPV/s would close if the regulator had failed.

 

With the cylinder cock/s open, there is full cylinder pressure up to the regulator. What Milly describes is that with the gas cocks (apparently) open and the RPV/s set, when she turns on a (unspecified) gas appliance, it initially ignites but shortly goes out - at which point the system, and so the RPV/s (and presumably the flow monitor on the regulator), will all lose pressure and close, completely cutting off the gas supply. This assumes that the cycle repeats after Milly has re-set all the valves to open, and then again tries to re-light the appliance. Thank you for pointing that out. That makes much more sense! :-D

[Brian Kirby]

weldted - 2020-08-06 8:51 AM

 

From our then new van in 2008, next new in 2012, both had secure motion regulators had regular problems and several replacements, fitted an inline filter between tank and regulator with replaceable cartridge not had one fail since. When bought our current one new in 2019, when having an underslung tank fitted specified an inline filter to be fitted. 11 months on no problems, although not much use during lockdown heater has run a lot over the winter.

I think this problem is peculiar to those using autogas. We have been using cylinder gas with Truma Secumotion regulators since 2007, and have yet to experience regulator failure. I think Milly's van is on cylinder gas, so the regulator should be less prone to oiling up.

[Derek Uzzell]

When bulkhead-mounted 30mbar regulators became the norm in the UK around 2004, reports of regulator failure soon began to appear.

 

The regulators that failed were ‘non-safety’ Truma/GOK products (SecuMotion/Drive-Safe was still in the future), bottled gas was being employed and the failures occurred in caravans as well as motorhomes.

 

There was considerable furore about this, with Truma being blamed by users and Truma blaming the providers of the bottled gas. The problem could not be provoked experimentally and there were lots of theories as to the culprit. The ‘solution’ involved recommendations as to where the regulator should be mounted and the length of the gas ‘pigtails’. Truma began to market a filter (that itself proved problematical) and - it is rumoured - the GOK regulator’s internals were modified to make them more resistant to the ‘oily residues’ that were causing the clogging. I rapidly went through three Truma/GOK regulators with my 2005 Hobby motorhome, but the third regulator was still going strong when the Hobby was sold in 2014.

 

There seems little doubt that the problem resulted from ‘oily residues’ in the gas, and it’s reasonable to assume that using autogas could well exacerbate matters. Browsing through these earlier threads may be of interest

 

https://forums.outandaboutlive.co.uk/forums/search/query.asp?action=search&searchforumid=all&keywords=oily+residues&author=&days=&Submit=Search

 

As I’ve said above, there’s little to be gained in discussing the wonders (or not!) of Truma’s SecuMotion/Drive-Safe system if Milly’s Autocruise motorhome does not have that system.