Gasit filling puzzle.

[BruceM]

I filled up with LPG for the first time today. The system is a professionally installed Gasit system.

The previous owner had supplied the van with both bottles almost full. I ran the tanks until both were empty. Both tanks had their stop taps turned off as per good filling practice.

 

On my return from filling I checked the tanks. One tank is full and the other remains empty. A bit of a puzzle. Any thoughts?

[pepe63xnotuse]

Hi

'Never had a refillable system but (and I may just be stating the obvious here?) is there no a change-over valve, between the two, that'd need to be operated? (or if it's "automatic", is possibly faulty?

 

(..or do change-over valves only govern the "take off" side of the system?)

 

..are there any check-valves in the hoses/fittings, that may've "stuck"?

[BruceM]

No change over valve. Also, the filling pipes bypass the gas stop valves and enter straight into the tops of the tanks. It occurred to me that these refillable tanks probably have a safety valve in the filler neck that has to be pushed open under pressure and that maybe the one on bottle 2 opened first with the consequence that the other valve would only open once bottle 2 had filled and the pressure had built up. Having said that I kept my finger on the button until it sounded as though filling has ceased. Maybe I should have waited longer??

[firedecisions]

Bruce,

 

I have a gaslow system fitted, on this system one cylinder fills first and then the second one. rather that taking your finger off the button, if you want to fill both tanks, keep the button pressed until the dispenser automatically shuts down, the system is designed to shut off at about 80% (which we would class as a "full cylinder" so you can not overfill them.

[Alanb]

I have experienced a similar problem in the past, when I had one empty and one part empty cylinder. From the delivered quantity of LPG, one of the cylinders failed to fail. The only thing that could have caused this was a sticking 80% cut off valve on the faulty cylinder, possibly coupled with a slightly low delivery pressure.

 

The cylinders had been filled in autumn and left unused until late spring. I am tempted to think that the LPG (and I stress liquid) expanded slightly in warmer weather forcing the 80% valves further into their seats, and that one stuck closed until after the attempt at re-filling. Subsequently we had no problems at a different filling station.

 

As Bruce's cylinders were full when he bought the vehicle, it would seem possible that a similar situation existed.

 

It is my current practice to draw gas from the cylinders alternately, so that both are exercised. If the gas runs out at night, and we hear the fridge ignition sparking, we just turn the fridge off until the next morning. Also as a result of our experience, we now do not top the gas at the end of a trip.

 

Alan

[BruceM]

Thanks all for the input. I’m thinking now that it may have been a case of ‘user error’. I’d assumed that one bottle was full. I’ve just checked it with a temperature sensor and it’s actually only half full. Looking at the receipt, it seems that I took on board 14.39 ltrs which is about 7 kg ( ? ). I think my two bottles are each 15kg tanks – so that’s potentially 26kgs of gas.

 

If this analysis is correct, what I don’t understand is that the pump seemed to stop filling even though my finger stayed on the button. Might the pump have run out of gas? Does this ever happen whilst filling? Do these pumps need to pause for breath??

[Robinhood]

BruceM - 2017-05-14 3:36 PM

 

I think my two bottles are each 15kg tanks – so that’s potentially 26kgs of gas.

 

 

...6kg or 11kg are by far the most common size.

 

 

Are you sure of the sizes (as for smaller bottles, other theories may be available. ;-) )

 

[BruceM]

Hmmm . . no, not sure of the size - the bottles are each about 470mm high excluding the fittings on the top. I've attached a picture. What do we reckon the weight is?

[BruceM]

OK - may have answered my own question. The bottles look similar to these http://www.gasit.co.uk/leisure-gas-refillable-products/-gas-it-refillable-bottles/gas-it-11kg-refillable-gas-bottle-with-level-/-contents-gauge-price-includes-vat.html which are 11kg bottles.

 

If that's the case then they can each take 21 litres of fuel at 80% fill.

 

So my total fill should have been about 42 litres rather than 14.39 litres, so still puzzled over the failure to take a full load - perhaps a return visit is required.

[Robinhood]

BruceM - 2017-05-14 7:39 PM

 

Hmmm . . no, not sure of the size - the bottles are each about 470mm high excluding the fittings on the top. I've attached a picture. What do we reckon the weight is?

 

c470mm to the top of the valve for a 6kg, c550m to the top of the valve for 11kg. The diameters of the two are rather different.

 

TBH, looking at your picture (and assuming it's the Dethleffs) I'd say the locker was designed for 2x11kg German cylinders, and that would lead me to believe (from the amount of locker floor-space occupied) that you have two 11kg refillables, at 21 litres each.

[monique.hubrechtsgm]

Please more precise ,a gas bottle will be stored in the upright position in your motor-home locker We use !2 kg light- weight from BP. IN PU material. NOT steel. LPG tanks are always steel and are laying horizontal on chassis level. Ask your dealer how it works. If not you are not allowed to drive your motor home.

[BruceM]

As a postscript . . . and a lesson on how confusing it can get when we’re diagnosing the wrong issue and there are two faults

 

To recap – I appeared to have run out of gas as the Truma went into fault mode and the gauges on the GasIt gas bottles registered zero. There was enough gas to cook with though.

 

Went to refill and only 14.39 litres went in.

 

Drove home and the canisters registered empty on the GasIt gauges– and the Truma still did not work.

 

Solution?

 

1. It seems that the gas bottles are full! Despite being correctly fitted the GasIt gauges need to be tapped to register – a little like we might with a wall barometer. Not impressed.

2. The Truma had quite an interesting fault. I’ve attached a photograph. If you focus on the rectangular metal boxes in the photo you’ll be looking at the gas solenoids. Feeling around with my hand one slid off. They’re held in place by a small nut (you can just see one on the box nearest to us). The nut for the furthest box had fallen off. It must have been working off every time we used it. The unit was services two years ago – I suspect the nut was either under tightened or thread lock was omitted. All back together now though and working perfectly.

 

Thank you to all for the helpful input.

 

[Charles]

If the solenoid coils come off they quickly overheat and melt. My experience is mainly with 230vac ones on refrigeration systems but I presume 12vdc will be the same. We used to put a screwdriver in the coil when it was off the valve body just in case the power came on. The fridge ones have got plastic caps that clip over the nuts so they can't come undone. If you can get a cable tie on the thread it would be worthwhile especially as its not upright.

[BruceM]

Thanks for the suggestion. The bolt end is flush to the nut when the nut is tight. I’ve used thread lock as well though so that will ensure it doesn’t move. It’s a reminder that in the rattle and roll world of motorhomes anything that’s not absolutely tight or thread locked will eventually work loose and fall off. When we picked up this van I worked my way through ever bolt and screw on the habitation unit and there were very few that did not need tightening. The ride's a lot quieter now . . .

[Alanb]

Charles - 2017-05-21 12:46 PM

 

If the solenoid coils come off they quickly overheat and melt. My experience is mainly with 230vac ones on refrigeration systems but I presume 12vdc will be the same..

 

I am sorry Charles, but you are incorrect in your presumption quoted above.

 

DC solenoid coils will not overheat if they are removed from the mechanism.

 

To elaborate the heating effect of an electric current (I) is equal to I x I x R watts. This is true for RMS or DC measurements. The current flowing in a DC circuit at a set voltage is determined by the resistance. However in an AC circuit the impedance, Z, is the determining factor. Impedance is the vector sum of resistance and reactance. Certainly in an AC circuit the reactance and hence the impedance of a coil will decrease if it is removed from its ferrous metal core. In inserting a screwdriver you were partially replacing the ferrous core, and hence partly retaining the inductive reactance of the coil.

 

Alan

[Derek Uzzell]

monique.hubrechts@gm - 2017-05-16 7:46 PM

 

Please more precise ,a gas bottle will be stored in the upright position in your motor-home locker We use !2 kg light- weight from BP. IN PU material. NOT steel. LPG tanks are always steel and are laying horizontal on chassis level. Ask your dealer how it works. If not you are not allowed to drive your motor home.

 

BP “Gas Light” composite-construction gas-bottles appeared in the UK in late-2005 and - for leisure-vehicle applications - were marketed through Truma(UK).

 

The bottles came in 5kg or 10kg sizes, but their large diameter meant that they would not fit in many UK-norm caravan/motorhome gas-lockers. The Gas Light bottle-outlet differs from the normal UK propane-bottle POL outlet, which also did not help!

 

A major selling-point was the claim that Gas Light bottles would be available and exchangeable throughout Europe, but they were, in fact, only available in a limited number of European countries (eg. not in France) and, because the bottle-outlet could vary from country to country, exchange was often not possible.

 

In 2012 BP withdrew from the bulk and containerised gas market and (where they could) sold off their bottled-gas businesses.

 

It is still possible to obtain and exchange “Gas Light” bottles in the UK, but this does not involve BP.

 

https://gasdeal.co.uk/gaslight-bottled-propane

 

Similarly in Belgium – BP no longer markets the bottles.

 

https://benegas.com/benegas-light/

 

The composite containers are made in Norway by Hexagon and the Safefill company markets a user-refillable variant in the UK.

 

http://www.safefill.co.uk/

 

[BruceM]

I woke up this morning thinking that there must be a more reliable way of monitoring gas levels then I followed the link to the Gas Light bottles. An ingeniously simple and reliable method of gas level monitoring. Their website implies safe for automotive and marine applications.

 

The only alternative I could come up with was something that monitored the weight of the cylinders. Maybe a pressure sensitive plate. The numbers could be relayed to a display either in the gas locker or even better, within the habitation unit.

[Derek Uzzell]

Worldwide there are quite a few manufacturers of composite portable LPG containers - some are listed below and the link shows various different designs

 

Amtrol-Alfa

Aygaz

Luxfer Gas Cylinders

Hexagon Ragasco

EVAS

Faber Industrie

GI&E Holding

Eurocamping

Aburi Composites

Santek

Rubis Caribbean

Eurocylinders

Atrama

Komposit-Praha

 

http://tinyurl.com/lfx3hhm

 

Composite gas bottles are pretty common in France (normally containing butane not propane) though it needs saying that - when a composite bottle is in a motorhome’s gas-locker - a powerful torch may be needed to check the contents-level.

 

All sorts of devices have been marketed to provide contents-level information for metal exchange-only gas-bottles. These include ‘sonar’-type and weighing-type systems. There’s an example of the latter here

 

http://www.thegreynomads.com.au/accessories/camping-products/gas-scale/

 

and (years ago) it used to be possible to buy an inexpensive small sprung-plate thingie that the lower edge of the bottle sat on and that measured the contents by weight. It was not easy to use, not very accurate and I think it’s no longer marketed.

 

As I’ve mentioned several times before, the type of magnetically-operated gauge used on the cheaper GAS-IT bottles (and on the original Gaslow canisters) have been criticised for being only able to measure the contents over a very restricted range, and have gained a reputation for being inaccurate and unreliable.

[BruceM]

Thank you for the information. I’m constantly amazed by the depth of knowledge this forum displays, absolutely superb.

 

Returning to the subject. It makes me wonder if a couple of theses http://www.ebay.co.uk/itm/150KG-DIGITAL-ELECTRONIC-LCD-BATHROOM-WEIGHING-SCALE-GLASS-NEW-WEIGHT-SCALES-/200977840000 would do the trick. £9 each delivered. In reality though I suspect I’ll stick to the simpler method of running one bottle at a time and when it runs out top up at the next LPG filling station.

 

[Robbo]

BruceM - 2017-05-22 7:43 PM

 

Thank you for the information. I’m constantly amazed by the depth of knowledge this forum displays, absolutely superb.

 

Returning to the subject. It makes me wonder if a couple of theses http://www.ebay.co.uk/itm/150KG-DIGITAL-ELECTRONIC-LCD-BATHROOM-WEIGHING-SCALE-GLASS-NEW-WEIGHT-SCALES-/200977840000 would do the trick. £9 each delivered. In reality though I suspect I’ll stick to the simpler method of running one bottle at a time and when it runs out top up at the next LPG filling station.

 

My moto for anything to do with the MH is to "keep it simple ???" (KISS).

 

A glass weighing scale supporting a metal bottle is only going to end in disaster - maybe even if you provide padding.

 

Favour your Option 2. However, be aware that frequent filling up in Europe where a mix of butane/propane is generally provided, can lower the pressure and prevent high consumption appliances, such as heating, from working. This can occur before the bottle is completely exhausted.

 

Best to fill up in UK whenever possible to get 100% propane. My 10 year old refillable became a victim of low pressure through too much filling in mainland Europe. I had to purge the bottle and refill with UK propane - everything now OK.

 

 

[Derek Uzzell]

In France (where the butane content of ‘autogas’ can be high) two products are marketed to combat reduced vaporisation of the gas in cold weather. One is a simple insulating blanket that wraps round the bottle

 

https://lavi.fr/categories/kit-gpl/piece-detachee-kit-gpl/reservoir-gpl-gaslow-r67/couverture-isolante-pour-reservoir-gaz-11kg.html

 

and the other surrounds the lower part of the bottle and is connected to the leisure-vehicle’s warm-air trunking

 

http://www.narbonneaccessoires.fr/nos-accessoires/gaz/reservoir-gpl/chausson-thermique-333124-borel.html

[Alanb]

Derek Uzzell - 2017-05-22 9:28 PM

 

In France (where the butane content of ‘autogas’ can be high) two products are marketed to combat reduced vaporisation of the gas in cold weather. One is a simple insulating blanket that wraps round the bottle

 

 

I wonder if that would work for long? Once the lpg had cooled down due to extracting the latent heat of vaporisation of the gas drawn off, would not blanket reduce external heat flow into the cylinder?

 

Alan

[Derek Uzzell]

It’s a motorhome ‘accessory’ and, by definition, does not have to actually work. ;-)

[monique.hubrechtsgm]

In case it is dark, yes but not at brought day light. A small light is sufficient and they are light weight. It is the best bottle on the market if you are able to use the last drop of it.