Low gas pressure

seisobs

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Hello people,

Been out in our 2007 avantgarde compass twice now, last time we wre out we had little to zero gas pressure, 2 X 6Kg bottles both half full, tried both same problem, all connections tight.

Any help / suggestions welcome b4 I take it to a motor-home dealer who will charge me the earth to look at it.

Cheers
Jake
 

Robmac

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Are you using Butane (Blue bottles) or Propane (Red bottles). Butane performs very poorly in cold weather, whereas Propane will burn all through the Winter.
 

Wooie1958

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Sounds very much like the regulator is blocked up and full of gunk.

If it is then a new one is needed and it wants fitting higher that the valve outlets on top of the bottles.

The vans about the right age when they had big big problems with them.
 

seisobs

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Thanks Guy's, it's Butane by the way, so you all suggest propand, I assume I will have to change the regulator.
Cheers
Jake
 

channa

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Butane this time of year has difficulty gassing albeit not convinced thats the problem ...change to propane if camping over winter, 37 mbar reg I guarantee issue solved.

Only other question is when the hoses changed ? LpG is a a by produc od oil distillation a "dirty " gas refill could cause ( will ) cause problems,

If you are camping over winter 37 mbar *(propane ) reg and a change to propane should cure any issues

Channa
 

Roger

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You can buy a 12v block heater that is installed just prior to the regulator which usually resolves the problem of the regulator freezing up.
 

lebesset

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good point about the on board 30mB regulator , 37mB regulators are obsolete now

presuming it IS an on board ..... although it is possible to buy adaptors , because the pigtails are undoubtedly 7 years old now much better to buy new ones to fit the propane bottles if memory serves than have a 10 year life
 

channa

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good point about the on board 30mB regulator , 37mB regulators are obsolete now

presuming it IS an on board ..... although it is possible to buy adaptors , because the pigtails are undoubtedly 7 years old now much better to buy new ones to fit the propane bottles if memory serves than have a 10 year life
30 mb regulators have been the standard since 2002, 37 mbar regs are still in use in statics. Pigtails should be replaced every 10 years. on your French ones there will be an expiry date , on british ones we print the date of manufacture.

I personally dont have issues with a 37 mbar reg on a Motorhome /Tourer as the jetting on the appliances are the same.

Channa
 

lebesset

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regent

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I had same problem. The regulator must be above the cylinder outlet. Butane is no good in winter. Truma spent much money investigating contaminated gas and have come up with a gas filter for about £70 I think. The best pigtail is the wire re-enforced mesh one.
 

channa

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Quite frankly anyone installing the regulator below the bottles should be shot !! Twice !!! LPG is susceptible to revert back to its origanl state I.e oil hence often a quick gander at a pig tail it isn't uncommon to see a yellow sludge.

This time of year now the frosts have arrived, I wouldnt even entertain butane it has difficulty gassing at 4-5 degrees Propane will give up the ghost at -47 degrees which if it is that cold we have bigger problems than boiling the kettle for a cuppa.

Channa
 

lebesset

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I@ just hate threads where the OP just disappears without giving the result
 

pughed2

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low gas pressure

when I was checking what size and type of gas to use some months ago, a gas distribution agent told me that under some conditions larger gas bottles can freeze the supply so losing pressure......I cannot remember what reasons, but if you incurred that problem you just need to talk to a supplier who knows his business......steve bristol
 

channa

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For Lpg to gas it draws heat through the skin of the vessel in which it is contained. The term is "wetted surface area" in a typical bottle physics applies again warm water trickled down the side will form the ice ring so one can calculate the remaining contents. Because of how the liquid gasses this explains why the myth of wrapping a gas bottle in insulation is detrimental. my point is we can see the marvel of phyisics at work, physics becomes tangible.

The issue of smaller bottles is a different matter... When we run appliances, we are drawing gas off the bottle, with smaller bottles fire, hob, fridge all at once is too much ..i.e we are demanding more gas than the bottle can convert liquid to gas and the system grinds to a halt. The total demand is known as "take off rate" and elementary to anyone designing their own system for a few simple calculations.( bigger bottles have a greater wetted surface so therefore can accopmodate a bigger take off rate ) i would agree and slightly confused by the gas agents comments in the earlier post .

Channa

I would
 

channa

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I am pretty sure you mean liquid to gas to avoid confusion.

If I were a teacher (which I am not ) I would use water as the learning example , many folk have forgotten or have difficulty grasping the concept of latent heat . When we apply energy to a gas ( heat in the case of lpg drawn through the skin of the bottle) the gas or water reaches a boiling point 100 degrees with water at sea level ( the boiling temperature reduces with altitude reason being less atmospheric pressure on the liquid therefore with the stimulation of heat, molecules can move quicker and boil ) anyway that aside we have a boiling point for our gas...we continue to add more heat and nothing happens ...then bingo the liquid water turns to steam !! therefore latent heat is the difference between boling point and vapour point . To the motorhomer, it is important the liquid gas can turn to vapour, it doesnt go liquid vapour liquid really ....so all this science aside , Butane has difficulty turning to the vapour we require at 4 to 5 degrees meanwhile propane will vaporisae to round about -47 .....hence Propane is a better winter gas than butane .

Channa
 
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