Gas pressure question

Saguday

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Swapped out one of the two 907 calor tanks last weekend so we now have one-and-a-half gas bottles hooked in with a changeover valve between them. System hadn't been used this year.

When we went to brew a cuppa we got very feeble gas pressure through to the stove - each burner just about lights but you'd need about 2 weeks to boil a kettle so gave up. Tried switching to each bottle but with no change in flame behaviour.

There is a solenoid safety cutout in the gas line, which I can *hear* operate. There is a pressure regulator in-line and there are flame failure cutouts on the burners on the (Force 10) stove.

Anyone suggest what I might start tinkering with? Or should I just call in the gas man?
 
Swapped out one of the two 907 calor tanks last weekend so we now have one-and-a-half gas bottles hooked in with a changeover valve between them. System hadn't been used this year.

When we went to brew a cuppa we got very feeble gas pressure through to the stove - each burner just about lights but you'd need about 2 weeks to boil a kettle so gave up. Tried switching to each bottle but with no change in flame behaviour.

There is a solenoid safety cutout in the gas line, which I can *hear* operate. There is a pressure regulator in-line and there are flame failure cutouts on the burners on the (Force 10) stove.

Anyone suggest what I might start tinkering with? Or should I just call in the gas man?

probably the bottles were cold so didnt produce sufficient gas
propane are much better this time of year
 
I'd agree that at this time of year it's likely to be bottle temperature. If warming the bottles doesn't improve things, then maybe you should check out the poses and components. I seem to recall there is an issue with plasticisers dissoving out of the hoses particularly if any liquid (gas) has got at them, which can cause a restriction or "modify" the pressure from the regulator. Butane doesn't like to be below 5 degrees, but Propane can go significantly below freezing.

Rob.
 
Had the same problem earlier this year. Turned out to be a defective regulator. As it was less than 1 year old it was replaced by manufacturer.

It appears that there was a batch of regulators from last year that were defective.

There was a fix available that involved taking out the filter on the inlet of the regulator and turning the screw inside by 1/2 a turn. I wasn't happy with that.
 
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If the gas is butane and the bottle temperature was below about 3°C then the temperature may have been a factor

Otherwise I would suspect the regulator.

Not been that cold has it ?


I had a regulator stick shut once when it had not been used for a lengthy period. I sucked on the outlet (after removing it from the bottle!) That freed it and was no more trouble until I broke it.
 
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Surely it hasn't been THAT cold in Essex yet this year! My guess is the regulator as well, especially as it hasn't been used for quite a time. As an emergency temporary fix a squirt of WD40 in each end will often free it, but certainly not advocated as good practice.

Edit: Sorry VicS ....you beat me by 2 minutes <grin>
 
Since it was in the mid-high teens in Tollesbury at the weekend with blue skies and sunshine I suspect it isn't the bottles being too cold :)

My hunch was the regulator, just not sure what to do about it. It was installed a couple of years ago. I'll try the blowy-sucky thing, then the WD40 and if that doesn't work I'll have to look for a new one.

Thanks all :)
 
On one occasion I fitted a full campingaz cyliner and immediately the gas flame was not at all right. The flame flickered quite a bit and would not stay lit. The cylinder had been sitting in the locker on the boat for some months. Giving the cylinder a shake to stir the liquid gas solved the problem.

It doesn't exclude the possibility of a faulty regulator or a faulty gas hose.
 
Since it was in the mid-high teens in Tollesbury at the weekend with blue skies and sunshine I suspect it isn't the bottles being too cold :)

My hunch was the regulator, just not sure what to do about it. It was installed a couple of years ago. I'll try the blowy-sucky thing, then the WD40 and if that doesn't work I'll have to look for a new one.

Thanks all :)

drip feed the info :confused:
 
drip feed the info :confused:

Nope, wasn't the intention, nor to cause offence - I did mention in my OP that this was last weekend, which was a beauty on the Muddy Coast :D

My hunch was the regulator, in all probability, but I didn't want to bias the response so tried to provide all the facts as I had them without offering my own opinion :rolleyes:
 
Nope, wasn't the intention, nor to cause offence - I did mention in my OP that this was last weekend, which was a beauty on the Muddy Coast :D

My hunch was the regulator, in all probability, but I didn't want to bias the response so tried to provide all the facts as I had them without offering my own opinion :rolleyes:


no offence taken ;)
it was cold over friday & saturday nights
 
On one occasion I fitted a full campingaz cyliner and immediately the gas flame was not at all right. The flame flickered quite a bit and would not stay lit. The cylinder had been sitting in the locker on the boat for some months. Giving the cylinder a shake to stir the liquid gas solved the problem.

It doesn't exclude the possibility of a faulty regulator or a faulty gas hose.

I did pick both bottles up and sloshed them around a bit, I'd just carried the new one several hundred meters and jiggled it around to put it in the locker. I'll focus on the regulator when I'm next down.
 
I may be imagining things (not unusual) but isn't there a stench agent in the liquid gas which somehow forms (or is generated by) small particles of some chemical ? There is usually a tinkling sound in empty bottles when shaken.

IIRC these can get stuck in the regulator gubbins and need blowing out by reverse flow.


I'll ferret for more info.


Ferret edit. Here's some detail about checking a regulator, including the comment that a blockage in the air vent may cause flow problems. HTH.

http://www.documentation.emersonprocess.com/groups/public/documents/bulletins/d450144t012.pdf
 
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Low temp - propane is best.

Sloshing the bottle around (to stir up the contents) will not help. What it will do is transfer some heat from the uppper empty half of the cylinder to the liquid making it boil off more easily.
As gas is drawn off the liquid cools down and if the liquid temperature drops below around 0 deg c it will not boil off gas - so low pressure. The liquid temperature will be lower than air temperature - how much depends upon how much gas is being used.

Many years ago (as a caravanner) I remember seeing a colleague proudly showing me his butane cylinder wrapped in a domestic hot water tank jacket - he explained to keep the gas warm! He couldn't understand why he was having probems! What he had inadvertently done was successfully insulate the cylinder from the surrounding air - so the cylinder became a fridge.

Even if the air temperature does not drop as low as 3 deg, if the cylinder is insulated from the surrounding air due to poor ventillation of the gas locker it can easily get cold enough to cause problems. In such cases the cylinder will feel very cold, may have a lot of condensation or even ice up-to the level of the gas.

If this is the problem then switch to propane, this boils off at around -40 deg rather than around 0 deg C.
-40 also happens to be the same temp in both F and C.
 
-40 also happens to be the same temp in both F and C.

Which prompts me to post the "alternative formula" for converting °F to °C, and vice versa

  • Add 40
  • To convert °F to °C multiply by 5 and divide by 9
    or
  • To convert °C to °F multiply by 9 and divide by 5
  • Subtract 40
 
sounds like lack of use, a bit of wd or new regulator, give the bottles a good shake and lay on them a hot towel.
Changeover automatic valves fail and always stop full use of the bottle, so try just having a regulator on each bottle with a manual change over valve/manifold. Hope it helps.
 
The changeover valve is manual, so it's not that that's the problem, and since I had just bought one of the gas bottles, which had been standing outside in bright sunshine, I ruled out cold gas as being the problem.

Thanks for the regulator maintenance notes Sarabande
 
Not sure whther it's what you're having problems with here, but I stumbled today on a couple of references on caravan parts websites to an apparently ongoing issue with gas regulators getting jammed up by an oily substance.

One reference suggested the source of such oily substance was unknown or disputed, another suggested it was (or could be) leaching from the 'rubber' gas hoses, and offered for sale replacement bottle hoses in stainless steel.

As regulators are relatively cheap and don't last forever anyway, might be worth changing if the other suggestions don't sort the problem?
 
Not sure whther it's what you're having problems with here, but I stumbled today on a couple of references on caravan parts websites to an apparently ongoing issue with gas regulators getting jammed up by an oily substance.

One reference suggested the source of such oily substance was unknown or disputed, another suggested it was (or could be) leaching from the 'rubber' gas hoses, and offered for sale replacement bottle hoses in stainless steel.


As regulators are relatively cheap and don't last forever anyway, might be worth changing if the other suggestions don't sort the problem?

It is recommended that regulators are replaced every 10 years and hoses every 5.
 
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