Gaslow - Not Getting a Full Refill

[Dmeehan]

Hi

 

Our first time travelling with the Gaslow LPG system, and we are getting somewhat erratic refills. We have two 11Kg bottles fitted, and use one of them until empty before seeking a refill. We have been in the habit of using the left tank until empty, keeping the right tank as the reserve.

 

The left tank appears to either stop delivering fuel before its empty, or fails to fill properly.

 

On the first and fourth occasions we switched bottles as the heating switched off on both of these occasions. On the second and third occasions, the gauge was completely red, and we switched preemptively as we had a long, cold night to endure, and thought this convenient timing. Of course the gauge could have been misleading us.

 

Below are the number of litres given on each refill. There appears to be no way of isolating the bottles when refilling, so assume it will just stop when both are full.

 

I am aware that there is an 80% cutoff, and that an 11KG cylinder should hold something like 21 litres at 80%.

 

The first date was after the left tank (the one we query) went empty. i.e. no gas coming out, not going by the gauge, and the second tank had not been in use but was in an indeterminate state (secondhand van, new to us).

 

The middle three refills were after the left tank was either empty or the gauge was completely red, and we'd drawn off some of the right tank, perhaps a days worth which seems to equate to about 15% going by our current refill frequency.

 

The gauge is on the regulator and therefore common to both tanks.

 

The final fill was after the right tank was run to empty (no gas, gauge also showing completely empty), and as you can see took a lot more onboard.

 

Also note that the gauge whilst using the right tank was constantly changing its mind - one day it would be almost completely red, other times back near to green. This was while travelling through the Pyrenees, so we think was down to air pressure changes as we went up and down the mountains on a daily basis.

 

Date Litres

Thu, 27 Oct 2011 26.93

Mon, 14 Nov 2011 19.06

Tue, 22 Nov 2011 13.21

Mon, 28 Nov 2011 12.00

Thu, 8 Dec 2011 21.74

 

There is always a faint smell of gas around the locker, but I wouldn't call this alarming, and we queried it with the dealer who said it was normal.

 

When filling, I always hold the button in and wait for the pump to stop filling, then press the button a couple more times to make sure its topped off (although have yet to notice any more gas going in).

 

So, there's all the relevant data I can give you. Question is, could this somehow be a faulty tank, how can you tell if its refilling properly? Can you explain the disparity?

 

 

 

[postnote]

Regarding the bottle gauge, I know that Gaslow state that this one is not very accurate and you would get a more accurate reading from an in line gauge. Yes sold by them as an extra.

 

I know I will be attacked for this comment but being a liquid it does fluctuate in volume depending on temperature. So when hotter such as the summer it will expand and the opposite in cold winter months.

 

We have experienced the bottle gauge showing empty and on filling would only take just over 10ltrs and we have the large 11kg (21.5ltr) bottle.

Would recommend the inline hose gauge. Hope that helped?

[Derek Uzzell]

Dave

 

Gaslow's brochure

 

http://www.gaslow.co.uk/pdf/Gaslow-2011-brochure.pdf

 

cofirms your observation that their larger cylinder should be able to contain 21 litres of LPG at 80% capacity.

 

There are two types of Gaslow gauge.

 

1: The newer sort of gauge described on Page 2 of the brochure. This is integrated into the bottle and employs a float-mechanism that shows the level of liquid LPG in the bottle in the range 50% - 18% of the bottle's 80% capacity. Due to the limitations of the float-mechanism this gauge can only provide 'generic' reading above 50% or below 18%.

 

2: The traditional type of Gaslow gauge shown on Pages 10 through 13 of the brochure. This reacts to pressure and offers a useful means of testing for leaks in the leisure-vehicle's gas system. But it's valueless for providing reliable information about percentage levels of liquid LPG remaining in a gas-bottle. It will tell you when the bottle is in its death throes content's-wise, but you'll know that anyway as none of your gas appliances will function - but for any other contents reading, forget it!

 

It seems that you have a pressure-sensitive Gaslow gauge and, in that case, you'd be better off using a ouija-board for 'partial' contents readings.

 

In a scenario where you are certain that one of your bottles is genuinely empty and the other at its 80% capacity maximum, you should be able to put roughly 21 litres of LPG into the empty bottle. If you cannot, then the bottle's 80% cut-off valve is cutting off too soon.

 

If you rely on your Gaslow gauge to tell you when a bottle is approaching empty, choose (as you've done) to switch to the other bottle proactively, and refill sometime later, there's absolutely no way of knowing how much LPG you'll be able to put into the two bottles. You can make an educated guess, but that's all. All that can be said is that, as your bottles are interconnected for refilling, when the LPG pump cuts off both bottles should be full (ie. you should then have roughly 42 litres of gas on board).

 

One other thing about Gaslow's pressure-sensitive gauges is that they are designed EITHER for butane gas OR for propane. However, in many Continental European countries 'autogas' is a butane/propane mixture. In France "GPL" is a mixture of (if I remember correctly) 65% butane/35% propane. This combination will produce cock-eyed readings on a Gaslow pressure-sensitive gauge - showing low on a propane gauge and high on a butane one. And, if you are whizzing up and down mountains, the combination of air-pressure and temperature changes will further complicate matters.

 

There have been reports in the distant past complaining that the amount of LPG that could be put in Gaslow bottles at the refill stage was lower than anticipated. This was before Gaslow introduced 'float' gauges and may well have involved people relying on a pressure-sensitive gauge. From the figures you've provided, I don't think there's anything wrong with your bottles.

 

A faint smell of gas in the locker is not unusual, but (as you've got a pressure-sensitive gauge) you might want to use it to test for leaks. General instructions on:

 

http://www.gaslow.co.uk/pdf/1610.pdf

 

(Good website incidentally...)

[hallii]

When abroad I can get a full 21 ltr refill. At my local garage I get 18 or 19 ltrs depending upon the phase of the moon, whether it's a Monday or Friday, or whether it's warm or cold etc etc.,

 

I suspect that it is to do with the setting of the back pressure cut off valve on the pumps, as the float valve in the cylinder begins to close as it fills, the pump valve senses back pressure and cuts off.

 

Then it just might be to do with the phase of the moon, whether it's a Monday or Friday, or whether it's warm or cold etc etc.,

 

H

 

 

[lennyhb]

Derek's comprehensive explanation is tops as usual. As you are using the the inline Gaslow gauge that as Derek explains is not very accurate the only way to really check the fill level you are getting would be to weight the bottles before & after filling, a bit of a pain but you should only need to do it once unless of course you have a faulty cut off valve.

[rupert123]

Why do you not fill the system and then leave one bottle turned off, run other one out and then refill at the first opportunity, at least this will give you some idea. I would throw the gauge away and get an auto changover valve then just look in the locker once a week to see if bottles have changed over. You then have plenty of time to refill.

[neillking]

rupert123 - 2011-12-11 11:35 AM... I would throw the gauge away and get an auto changover valve then just look in the locker once a week to see if bottles have changed over. You then have plenty of time to refill.

Absolutely right. We often struggle to persuade new Gaslow customers to abandon the old habits left over from the one-empty-exchange-bottle scenario. Twin gaslow bottles should be treated as a single tank system linked together with auto-change or even just a T-piece. Then use the on-bottle gauges of the newer tanks (post-08) to tell you that you're on the last quarter of your supply and refill when convenient. After all that's how you manage your diesel isn't it? Whats the difference? 

You will get different fills in different parts of Europe and at different altitudes but if operating roughly quarter-to-full on the built-in float gauges it doesn't generally matter much. I've been using refillables like this for about 10 years over much of Europe and find a fairly relaxed approach works best. Trying to get too precise seems to just result in too many false alarms.

[Dmeehan]

Thanks to everyone for their great replies. I wasn't aware of the auto change over, so may investigate one of those once we return from this trip.

 

Given that the pressure gauge is pretty unreliable, leaving both bottles open until you get a warning seems a bit haphazard - the new gauge mounted bottles would be fine in this situation, as they employ a more reliable measurement, and one would cross-check the other.

 

I'm making a point of running the questionable tank down at the moment, and will report what the refill uses for the sake of completeness. For the next week or so we are more likely to be at lower altitudes which should help to make it more reliable.

 

Cheers

Dave

 

 

[Dave Newell]

We had this very situation arise with one customer with Gaslow system, 2x11kg cyls but even filling both from empty they would only take about 22 litres, roughly half what it should have taken. After a couple of total refills (both cyls completely emptied) confirmed the problem we referred it to Gaslow who had not seen this issue before, I have no reason to doubt this. Customer visited Gaslow in Loughborough where they confirmed the problem and simply replaced both cyls with new ones.

 

My advice would be to confirm whether there is a problem as outlined above, if the cyls are not accepting their proper fill quantity then contact your supplying dealer and ask to be referred to Gaslow.

 

D.

[Dmeehan]

Dave,

 

Thanks, that's great help. I will confirm the problem before continuing. Given that its a 2006 used van (5th owner), and going by the age given for the introduction of the in-bottle gauges (2008), I suspect first or second owner have them fitted. I doubt we have any comeback with either the fitter or the dealer who sold us the van, but Gaslow themselves might be obliging, depending on what sort of warranty they give.

 

At the end of the day based on experience so far, we can go at least a week before needing to worry about a refill (nearer 2), which isn't much of a problem unless we are in a country with limited LPG stations. Mind you, we are on our way to Spain, so that might yet become a problem!

 

Cheers

Dave

 

 

[lennyhb]

Dmeehan - 2011-12-11 4:50 PM

 

I'm making a point of running the questionable tank down at the moment, and will report what the refill uses for the sake of completeness. For the next week or so we are more likely to be at lower altitudes which should help to make it more reliable.

 

Cheers

Dave

 

 

I would still weigh the other tank to ensure it is full otherwise your results could be meaningless as the filling pipe is connected to both tanks.

I realise you are travelling at the moment so it may not be possible just yet.

[Brambles]

Would there me any merit in removimg the tank when empty and turning upside down and purging any contaminates which may have collected at the bottom of the tank via the outlet connection valve?

I know when bottles are new the 1st fill is not successful because of air in the tank having to be compressed so also raised the question in my mind if you have a slight leak, when empty and driving back down from high altitudes, or a drop in temperature, could the bottle then suck in air?