how do you know gas is near empty (1 Viewer)

vwalan

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could have got a propane bottle filler n saved youself couple of hundred quid. never mind. have fun filling up in spain.
 

barryd

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Yeah and your not allowed to fill them up on forecourts from what I heard if its what I think you are talking about. Spain is certainly not on my priority list of places to visit either!
 

45eEver

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BarryD, if you

  • fit an auto gas connector to the side of your M/H
  • Run a high pressure hose with a cylinder connector to your gas locker
You should be OK.
That's what they have the gas on the forecourt for.
Filling through autogas connectors.

Connect the high pressure hose to your cylinder when you swap cylinders so you are ready.

The auto gas connector has an excess flow valve in it.
If something goes wrong when you disconnect the line from the pump
The excess flow valve shuts off the supply.

The downside is that the hose from the auto gas connector to the cylinder connector is full of liquid, which will squirt about the jockey when you disconnect.

I fitted a ball valve from a hydraulic line maker next the cylinder connector on my refuelling hose.
I shut the cylinder valve and the ball valve before I disconnect the cylinder, which I do off the forecourt in a well ventilated area like on the top of rising ground in an area without drains, culverts, cellars etc.
Then I bleed a little of the liquid gas out of the hydraulic hose to give the liquid inside room to expand as the temperature rises.

Incidentally, if you fill your cylinders in the cool of the morning, you get more LPG for your donks.

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45eEver

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BarryD, if you

  • fit an auto gas connector to the side of your M/H
  • Run a high pressure hose with a bottle connector to your gas locker
You should be OK.
That's what they have the gas on the forcourt for.
Filling through autogas connectors.

The auto gas connector has an excess flow valve in it.
If something goes wrong when you disconnect the line from the pump
The excess flow valve shuts off the supply.

The downside is that the hose from the auto gas connector to the cylinder connector is full of liquid, which will squirt about the jockey when you disconnect.

I fitted a ball valve from a hydraulic line maker next the cylinder connector on my refuelling hose.
I shut the cylinder valve and the ball valve before I disconnect the cylinder, which I do off the forecourt in a well ventilated area like on the top of rising ground in an area without drains, culverts, cellars etc.
Then I bleed a little of the liquid gas out of the hydraulic hose to give the liquid inside room to expand as the temperature rises.

Incidentally, if you fill your cylinders in the cool of the morning, you get more LPG for your donks.
 
Nov 28, 2007
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Funny Money, when you say you can smell it.

Do you smell the difference: -

When it burns with an open flame (cooker ring)?
When it burns with an enclosed flame (heater)?

When it's switched off?

Between when you turn the gas on and when you light it?
Ie unburnt gas.


45 ER It is when the cooker ring is on that you can smell it, a distinct odour, usually a day before you run out. I think the post by Tony Lee might have the answer as to why, i will copy it below.

"I think it is because the LPG odouriser (mercaptan?) settles out a bit and is concentrated at the bottom of the tank and is more noticeable when you are lighting the gas."
 

45eEver

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Yep, it could be the stenchant settling out.
I'm not sure why is would though.
To put it crudely, the stenchant should spread out like a f*rt in the night.
The tecnical term is 'Brownian Motion'
Nothing to do with our dearly beloved PM motions though.
Brownian motion - Wikipedia, the free encyclopedia

My money was on that your pressure at the burner jet dropped as your cylinder starts to run out.
Lower pressure at the burner means a cooler flame.
A cooler flame will produce different by-products than the those from a hot flame.
The stenchant changes it's smell in the flame, so it could be that .

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pappajohn

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it cant be the lack off pressure at the appliance.

as long as there is liquid gas in the cylinder the pressure will always be higher than the regulated pressure at the appliance.

no matter whether there is 10psi or 1000psi in the bottle, if the reg needs 1psi to work then that is the pressure at the jets.
yes, i know its in millibar but i cant work that out..:Doh:

i think, not 100%, gas vapour has 600 times the volume of liquid gas so the bottle will always be at the same pressure until the liquid gas has been used then the pressure will start to drop as the vapour is used and not replaced.
 

pappajohn

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At normal temperatures and pressures, LPG will evaporate. Because of this, LPG is supplied in pressurised steel bottles. In order to allow for thermal expansion of the contained liquid, these bottles are not filled completely; typically, they are filled to between 80% and 85% of their capacity.(1) The ratio between the volumes of the vaporised gas and the liquefied gas varies depending on composition, pressure and temperature, but is typically around 250:1.
(2)The pressure at which LPG becomes liquid, called its vapour pressure, likewise varies depending on composition and temperature; for example, it is approximately 220 kilopascals (2.2 bar) for pure butane at 20 °C (68 °F), and approximately 2.2 megapascals (22 bar) for pure propane at 55 °C (131 °F).

(1) Ok i was wrong about the volume:Doh:....its 250:1 not 600:1

(2) thats 319psi (@55degC) in the bottle and must remain at or above this pressure to remain liquid until gas vapour is needed by opening a tap/valve so allowing the pressure to fall below 319psi and turning liquid to vapour until the valve is turned off and the liquid will continue to release vapour until the released pressure is replaced.

and you only need 30millibar. ( 0.43511323 psi )

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barryd

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BarryD, if you

  • fit an auto gas connector to the side of your M/H
  • Run a high pressure hose with a bottle connector to your gas locker
You should be OK.
That's what they have the gas on the forcourt for.
Filling through autogas connectors.

The auto gas connector has an excess flow valve in it.
If something goes wrong when you disconnect the line from the pump
The excess flow valve shuts off the supply.

The downside is that the hose from the auto gas connector to the cylinder connector is full of liquid, which will squirt about the jockey when you disconnect.

I fitted a ball valve from a hydraulic line maker next the cylinder connector on my refuelling hose.
I shut the cylinder valve and the ball valve before I disconnect the cylinder, which I do off the forecourt in a well ventilated area like on the top of rising ground in an area without drains, culverts, cellars etc.
Then I bleed a little of the liquid gas out of the hydraulic hose to give the liquid inside room to expand as the temperature rises.

Incidentally, if you fill your cylinders in the cool of the morning, you get more LPG for your donks.

Isnt that what I have with the Gaslow system. I fitted Gaslow as this is what everyone seemed to recommend. Your right though it does squirt back at you when you disconnect which is a bit scary at first. You have to remember I am a complete dunce when it comes to fitting anything and certainly wouldnt even consider messing on with hoses and gas bottles. I would rather pay a pro to fit it properly and know its going to work (hopfully). I am interested why you should get more LPG for your money when its cold. How come or are you joking?
 

pappajohn

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Isnt that what I have with the Gaslow system. I fitted Gaslow as this is what everyone seemed to recommend. Your right though it does squirt back at you when you disconnect which is a bit scary at first. You have to remember I am a complete dunce when it comes to fitting anything and certainly wouldnt even consider messing on with hoses and gas bottles. I would rather pay a pro to fit it properly and know its going to work (hopfully). I am interested why you should get more LPG for your money when its cold. How come or are you joking?[/QUOTE]

dont know if its worth it for LPG 'cos the auto valve shuts off at 80% full and when it expands it will be over the recommended fill limit.

definately works for petrol though. cold petrol is denser than warm petrol so you do indeed get more for your pound.
go mid afternoon and the underground tanks have warmed up and the petrol has expanded so less for your pound.
i reckon the amount is miniscule and not worth the bother though. :Blush:
 

Compass57

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popping

:Eeek:I'm new here but i have had a little experiance regarding gas bottles.
My mum and dad owned a static van many many years ago, they are both dead now, anywayup, I beleive the first sign a bottle is running low is when the flame starts to make a popping noise. I noticed this many times while in a static, bottles always ran out while i was using van...I reckon my brother who also used the van planned it that way so I had to pay for a new one, craffty bugger!
Noticed the other week my hob ring was popping, luckily i have two so there's no problem when one gives up the ghost so to speak...
Being a single chap I'm very concerned with waste not want not policy of use so therefore I use very little of everything, I wait until i'm back home before i wash pots.....lol:ROFLMAO:

Bip x:thumb:

PS...don't members read back posts? regarding sludg in bottom of bottle, it's a myth i tell you....:Doh:

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45eEver

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Liquid propane expands as it get warm.
That's why you can't fill the cylinder to full.

A litre of cold LPG expands to well over a litre when it's warm.

Petrol also expands, but not as much as LPG.
If you fill your petrol tank to full with cold petrol.
Then leave it parked in a sunny spot.
You will probably find it's leaked petrol.

Most petrol storage is underground so you always get cold petrol.
Many propane tanks stand in sun, by mid afternoon, they can be quite warm.
 

pappajohn

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Incidentally, if you fill your cylinders in the cool of the morning, you get more LPG for your donks.


Liquid propane expands as it get warm.
That's why you can't fill the cylinder to full.

A litre of cold LPG expands to well over a litre when it's warm.

.

sorry 45er, you just shot down your own advise there.

fill your bottle in the morning when the tank is cold and the gas will expand to well over its cold volume as it warms, which means you are OVERFILLING the bottle past a safe 80%
 

derekfaeberwick

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sorry 45er, you just shot down your own advise there.

fill your bottle in the morning when the tank is cold and the gas will expand to well over its cold volume as it warms, which means you are OVERFILLING the bottle past a safe 80%

He ain't, he only thinks he is. :winky:

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barryd

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All seems a bit anal to me. I will just top my gas up as easy as can be, every time I see an autogas station and if I ever run out I can use my spare LPG and if that runs out I must be in Mongolia so I will light a fire and dance around that thinking about you gas nerds and laughing my head off! :ROFLMAO:
 

vwalan

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oh well takes allsorts. didnt have to join in anyway! who spent all the money on old gas bottles, if you cant be safe to fill a bottle you arent safe to fill anything . even bulkhead mounting a fill point is only like changing a pipe. dance on we dont care. have a nice trip, enjoy mongo:ROFLMAO::ROFLMAO::ROFLMAO::thumb:
 

45eEver

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'fill your bottle in the morning when the tank is cold and the gas will expand to well over its cold volume as it warms, which means you are OVERFILLING the bottle past a safe 80%'

Duh!!!!

Where do they get their mumbo jumbo from?
If I'm filling to 80%,
how can I be over filling to past 80%?
Get your neurones into gear before you finger you engage your keyboard lads.

Propane gas cylinders should only be filled up to the 80% mark with LPG
so as to leave room for the LPG to expand when it gets V hot.

There's enough room in the space above the LPG for it too expand by 25%.

25% is ample safety margin.

That 25% tolerance is enough to cover the expansion from freezing cold to boiling hot and some.

Will someone else explain to the mumbo jumboers why 20% space at the top is a 25% safety margin please?

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barryd

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oh well takes allsorts. didnt have to join in anyway! who spent all the money on old gas bottles, if you cant be safe to fill a bottle you arent safe to fill anything . even bulkhead mounting a fill point is only like changing a pipe. dance on we dont care. have a nice trip, enjoy mongo:ROFLMAO::ROFLMAO::ROFLMAO::thumb:

Your right. Im not very good at filling bottles, just emptying them! Only having a joke cos I dont have a clue what your all on about an felt all excluded!:Smile: Your rig looks fantastic by the way!!!!
 

45eEver

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'Brownian? Motion? Stenchant? A stand up comedians dream come true!'

Watch this space.

More Dave Allen than stand up comedian though.
 

camper69

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'fill your bottle in the morning when the tank is cold and the gas will expand to well over its cold volume as it warms, which means you are OVERFILLING the bottle past a safe 80%'

Duh!!!!

Where do they get their mumbo jumbo from?
If I'm filling to 80%,
how can I be over filling to past 80%?
Get your neurones into gear before you finger you engage your keyboard lads.

Propane gas cylinders should only be filled up to the 80% mark with LPG
so as to leave room for the LPG to expand when it gets V hot.

There's enough room in the space above the LPG for it too expand by 25%.

25% is ample safety margin.

That 25% tolerance is enough to cover the expansion from freezing cold to boiling hot and some.

Will someone else explain to the mumbo jumboers why 20% space at the top is a 25% safety margin please?


Because 20 is a quarter of 80 ie 25%

Derek

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45eEver

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Barry D, if you look at it from the point of view of a man filling the propane tanks on his LPG fuelled 7.4 litre 8mpg leviathon does it still look DA?
 

45eEver

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You can convert a petrol engine to run on diesel Barry.
In fact, it's cheaper to run an M/H on propane than on diesel.

If you run on propane, you have to fit fuel cylinders in or under your M/H.

If you get 8mpg from your petrol M/H, you'll probably get 7mpg from propane.
However, since propane is half the price of petrol, it's a lot cheaper to run on propane.

At 7mpg you need some pretty big cylinders.
30 gals will only carry you around 200 miles.
If the LPG runs out, you have to switch to petrol.

30 gals of cold propane will carry you a little further than 30 gals of warm propane.
But costs the same.

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barryd

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Ah I see! thanks for the reply. Never knew you could convert a diesel. Still dont know what DA is though
 

45eEver

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You can convert diesels Barry, but wasn't very reliable.

Petrol engines convert easily.

DA = anal

Tighter than a duck's a**e.

They have to be water-tight or the duck'll sink, so the story goes.
 

lady jann

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propane is a liquid, when the pressure drops it becomes a gas, any residue will be at the bottom of the tank, gas leaves at the top. no problem, you know it is empty when the gas goes out. a gauge will only show when the last of the liquid has turned to gas and the pressure drops otherwise it is constant. Only genuine way is to use see through bottles then you can see what is left, why bother just carry a spare.

hi roger , why not use laughing gass ? its not quite so misserable when you run out !!!!:roflmto::ROFLMAO::ROFLMAO:

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barryd

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You can convert diesels Barry, but wasn't very reliable.

Petrol engines convert easily.

DA = anal

Tighter than a duck's a**e.

They have to be water-tight or the duck'll sink, so the story goes.


:ROFLMAO::ROFLMAO::ROFLMAO: I get it now so no its not really that anal then. Im off to play with me Gaslow.
 

pappajohn

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'fill your bottle in the morning when the tank is cold and the gas will expand to well over its cold volume as it warms, which means you are OVERFILLING the bottle past a safe 80%'

Duh!!!!

Where do they get their mumbo jumbo from?
If I'm filling to 80%,
how can I be over filling to past 80%?
Get your neurones into gear before you finger you engage your keyboard lads.

Propane gas cylinders should only be filled up to the 80% mark with LPG
so as to leave room for the LPG to expand when it gets V hot.

There's enough room in the space above the LPG for it too expand by 25%.

25% is ample safety margin.

That 25% tolerance is enough to cover the expansion from freezing cold to boiling hot and some.

Will someone else explain to the mumbo jumboers why 20% space at the top is a 25% safety margin please?

you just cant admit being beaten can you !!!!!

personally i think you are full of your own importance and a total wa**er.

back on the ignore list :Angry:
 

45eEver

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An oily contaminate that can collect in the bottom of gas cylinders.



http://www.calormarineshop.co.uk/lpg_glossary.htm

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