it all about?
home we don't really think much about power sources and capacities - it's
all there 'on tap'. In our
motorhomes things are rather different, we need a portable and reliable
heat source source and while you can 'have a hook-up' to mains electricity on
site, that may not always be convenient. Vehicles
normally rely on 12 volt batteries for mobile power but this just isn't
powerful enough for heating. For example if you used your battery to
run a small 1kW fire for space heating or the same power ring for cooking it would take 85 amps from
your leisure battery which would then last only about half an hour before
needing a major recharge!
answer for most of us is bottled gas - also known as Liquid Petroleum Gas,
LPG, Butane and Propane or sometimes as 'Calor Gas', this being the name
of the brand leader. It's convenient and very powerful and since it's
stored under pressure as a liquid you get lots of it in a very small space
- so it has become the fuel of choice for most motorcaravanners. The
container is a strong steel
bottle, and some portable sizes
contain enough gas for
use. The bottles are
readily available at home
and abroad, in
various sizes - usually described in Kg.
A gas bottle
is normally hired from the gas supplier for
a once-only payment though
increasingly suppliers will lend you a bottle for free.
The gas contents
are charged separately.
When a bottle is
empty it is simply exchanged for a
full one, for the price of
the gas only.
Unfortunately there is no standardisation of LPG bottles across Europe.
Refillable cylinders and fixed tanks are becoming far more popular
in part to get round the European problem but also because they are so
much more convenient. There's no lugging heavy bottles around, no searching for
the right kind of bottle and the great advantage of being able to top-up
whenever you want, just as you do with other fuels. It's a whole new way
of thinking about gas management - bliss!
Click here for a FAQ on refillables or
click here to go to our Gaslow
Shop pages (both new window).
the way the term bottle and cylinder are interchangeable here for
removable containers. A 'tank' on the other hand implies a fixed unit.
bottles must be used in an upright position to take off vapour from the
top of the bottle and not liquid which would be dangerous for 'habitation'
use. A 'regulator'
is also required to
control and stabilise the
gas pressure throughout the
life of the fill and to compensate for temperature changes. The
regulators are different for the different gases and the fixings are
different too so no mix-ups can occur. Most newer
vehicles have gas fittings and appliances designed to a new standard where a single 'universal' regulator
is fixed to the vehicle and the bottles are connected to that by high
pressure hoses known as
'pigtails'. The bottle and/or regulator
will be fitted with a
main on-off valve.
It is sensible to carry two bottles to avoid running out
- which always occurs at a
time - like the middle of the night! Most
'vans have built-in ventilated gas storage
lockers with room for two
bottles though not always
very large ones. We use twin bottles in our Hymer and at home
where we use LPG as fuel for our domestic gas hob. More recently we
converted the Hymer to Refillable Cylinders but stayed with two for the
purpose-made and built-in LPG tanks are used instead of portable bottles.
Fixed tanks and fixed Refillable Cylinders are refilled at special filling
points in a
similar way to the vehicle's fuel tank. Tanks usually hold much more gas
than a portable bottle, are very strongly made to withstand the pressure
and so are relatively large and very heavy. One advantage is that they are
easier to fill in various countries abroad, though some countries have
very few outlets. With the increasing availability of LPG at petrol stations
dedicated tanks are becoming more popular but remember that there can be a
significant effect on available payload. To use the Channel Tunnel the
tank capacity must be less than 47Kg, physically turned off at the tank
(often not easy / possible) and the gas must be exclusively for
The interesting hybrid is the refillable bottle
like the Gaslow unit,
we've had two fitted to our Hymer complete with a 'remote'
external filler and I must say they do seem to offer something of the best
of both worlds albeit at considerably greater initial expense than a free loan
bottle! The extra convenience both at home and abroad is most
welcome though and once installed the per Kilo/Litre running costs are
much lower. Such improvements also increase the asset value of the 'van
or can be moved on to a new vehicle - up to their 15 year life at least.
These are often fitted with Stainless Steel High Pressure Hoses to make
sure your regulator doesn't suffer from 'oiling'. Rubber hoses are
implicated in the recent oiling problems in newer systems.
Gas do I need?
are many good gas supply companies,
but for use on the move the best choice is one
nationwide, especially if you can only use the smaller bottles. Calor
is the market leader and
the company supplies both Butane and Propane. Butane,
usually in blue bottles, is heavier than Propane, and slightly more energy can be
stored in a given bottle size. Propane, although lighter than Butane, has
the advantage of remaining usable under freezing conditions and is
therefore the best choice for all-season motorcaravanning. Butane stops working as the temperature
falls towards 0° C and it can reach this very quickly because it is
self-cooling as it evaporates in use. In contrast Propane works well at very
low temperatures indeed. Since Propane also works OK at normal temperatures many motorcaravanners
like us use Propane all year round.
that gas bottles cool themselves as gas is consumed so butane can be
problematical even on cool mornings. When gas is delivered by
opening a valve the bottle
pressure is reduced and some of the the liquid vaporises, consuming heat
in the process,
the only heat available is in
the liquid so the liquid
necessarily fall. As gas is being consumed the
liquid in the gas bottle
will get colder than
its surroundings and when the air
the liquid gas can become so
cold that it cannot
vaporise. Propane will be OK right down to
about minus 40°
C and very few of us camp in temperatures like that!
At low temperatures and high gas consumption you might see frost forming
on the outside of the bottle,
a useful indication of gas level. If a Butane bottle starts to die in
low temperatures, gas flow
may be improved
by warming the bottle but only with safe heat like a container of hot
water standing beside
different gases, butane and propane have
to be bottled at very
different pressures, and traditionally they have each required their own
unique regulator to suit the
pressures required by the appliances.
In the UK the pressures were 28mbar
for butane and 37mbar for propane.
Newer, post 2004, and
vehicles use a common 30 mbar for either gas and some older German
motorhomes have a 50mbar system. Note that you cannot pick and choose
from these standards, you must use the one your appliances were designed
for. The regulators
for different gases cannot easily be
mixed up, since each has
a different fitting. These fittings were not
standardised throughout Europe but the new 2004 standard goes a long way
towards harmonising them. In the UK the range of
bottle sizes offered by
as Calor covers virtually all
needs. There is also an
Gaz, who supply smaller sizes
than Calor, suitable for some
smaller motorcaravans and
Their bottles are
available all over Western Europe
except Scandinavia but
contain mostly Butane for summer use and are quite expensive.
offer three bottle sizes
holding; Butane (blue), 4.5kg, 7kg and 15kg and Propane (red), 3.9, 6, or 13kg. Some
suppliers like FloGas also do a
slightly smaller 11Kg Propane which can be very useful
in some gas cupboards, especially imports, being only 305 mm dia. The largest Camping Gaz bottle holds 2.72kg of
Butane. Gaz also comes in
smaller sizes still but is
very expensive to buy compared with the larger UK bottles. In
addition to capacity all these bottles deliver gas at different rates - it can
be impossible to run all appliances simultaneously from the smaller
bottles but is no problem with the larger ones (see table).
Incidentally some suppliers will exchange any of their own bottles
for others of different sizes as
We have a long list of the many Flogas brands - if needed please
much will I need?
Gas can supply
virtually all of the
heat energy needs of a motorhome - hot water for washing and showering, washing
up, cooking, heating and refrigeration - possibly even air conditioning.
Most of these needs could be satisfied or supplemented by a mains hook-up
if available, or even by the site facilities in which case the gas
consumption could be very low indeed, albeit with some personal
inconvenience. We are quite fortunate in being able to just get two
11Kg Propane bottles in our gas cupboard, so with
22 Kg (~46L) available
don't have to change or refill bottles very often
and could at a pinch go for six weeks or more without needing gas.
we spent 21 nights away in indifferent weather during March April &
May and used just
11Kg bottle - about 1/2 Kg per day. We have a 2 burner hob, Truma
fire/blown air and water heating system and refrigerator, there are only
two of us but we very rarely use mains or any site facilities. We
are all different of course, others have reported consumption of about
2/3 Kg per day in summer
but at least these figures will give you a guide. Surprisingly many
people use more gas in summer than winter due to running a fridge flat out
in summer and using hook-ups in winter!.
are several safety regulations and features for LPG use. Our own
responsibilities include turning off all bottles when travelling* and when
on ferries or in tunnels as well as ensuring that the system is installed
by and regularly inspected by qualified people. Less obviously you
mustn't store things like batteries in the same cupboard due to the spark
risk and the rubber connection hoses should also be replaced at least
once every five
years. * There is a new safety device called Secumotion that
can be used while travelling.
appliances have flame failure devices built in, so if there's no heat
the gas shuts off automatically.
This is why you have to press and hold
the gas tap to light the burner - to give the thermocouple device time to
warm up. Releasing the tap early and seeing the flame go out is a
simple test that the flame failure device is still working! Possible
in the gas system are made obvious by adding an obnoxious smell to the
gas, so if you do get a leak - you will know! Any leaked
gas must of course be able to escape from the 'van and since LPG vapour is heavier
than air you will normally see floor vents in your gas locker and possibly under
appliances too, probably complete with anti-mouse netting. These holes
must not be covered even accidentally.
do I know when it will run out?
only a finite amount of gas in a bottle and no on-tap supply we have to
try to keep an
eye on the shrinking contents of
the bottle, and also try to
have a quick and
simple way to change to a new
bottle as soon as possible
after the first
one becomes empty. One thing you should never do with
gas is run out! To wake up
in the morning
or get back from the beach to find that the fridge has
been off for hours is not
good news. Having decided to carry two bottles it is important to
have a suitable change over device too.
units are available to
both bottles to be
connected to the 'van's
input, through a
manual or automatic
change-over valve. Although not traditionally fitted in the UK, automatic change-overs
offer great benefits and are now becoming increasingly popular.
Wrestling with a change over system in an external gas cupboard at
6 am on a
cold rainy morning is no fun at all!! Automatic valves need no
achieve a 'seamless' change-over, but
there is of course a need
to keep an eye on them in case
you finish up with two empty bottles. Our German Triomatic system
(illustrated) has an auto-changeover with a pressure valve to indicate which bottle is
in use and roughly how much gas is left. Other pressure sensing
devices like the Gaslow gauge will show a pressure drop if the user
watches it regularly. This unit is fitted into the gas line or onto each
regulator and also serves as a gas leak
detector since with all
off, including the bottle, the
pressure trapped in the gas
Such gauges are not 100% accurate but will certainly indicate 1/4 maybe
1/8th bottle clearly enough. The Gaslow auto-head has clear
indicators to show when a bottle empties and their latest refillable
cylinders have built-in float gauges accurately showing the level from
50% down to 18% remaining - perfectly adequate for all normal puposes.
Finally, how about going abroad?
bottle fittings are not standardised throughout Europe and the Calor
company do not operate on the
Continent, so it is necessary to carry enough gas to see you
through, possibly relying
more on hook-ups;
or you could emulate the locals,
and obtain a suitable bottle and regulator or alternative pigtail /
there. You can buy most
pigtails and adapters here too - see our shop at
www.motorcaravanning.co.uk One useful bottle,
offering 5-6 Kg of
gas with a larger 11-13
kg option can be found all
over Germany, Austria and
would only need to purchase
one bottle and regulator and by using the Continental bottle all
the time, with the Calor one
only to bridge the short gap while replacing
the empty one, a tour in
this area could last
The increasing use of user-refillable bottles from
Gaslow and also separate underslung gas tanks is largely driven by the
extra convenience when touring Europe, with a couple* of adaptors you can
top up whenever is convenient at any Autogas
point or filling station and there are thousands across most of the
continent. * NB: You now need three adapters, there is a new
quick-release fitting being introduced on new filling equipment and this
may appear anywhere - first spotted at Malaga and in Germany I believe.
Now on sale in our shop of course.
available abroad is the little
Camping Gaz 2.72 Butane.
This is a handy
'last ditch' reserve, and is
ideal for a gas barbecue as
well. Gaz adaptors are available here for UK regulators and it might
be wise to carry one just in case! Imported
European 'vans usually come with euro-fittings as standard, sometimes it's
easier to keep those and use adaptors for UK bottles, that way you may have
easy use abroad too!
Dedicated BBQ points are the best way to connect a
barbeque. Hard plumbed downstream of the regulator and fitted through
the vehicle wall you just add the supplied adapter to the BBQ Hose and
snap on/of to connect the barbie to the gas - simple, safe, convenient.
The new style 30Mbar remote regulators are fitted to the
vehicle itself with 'pigtails' connecting to the bottles. As a result it should now be
possible to simply carry spare pigtails to connect to 'strange' foreign
propane gas & bottle data kindly supplied by Calor Gas
Note how the
bigger bottle can deliver gas at about twice the rate of the smallest!
Dim dia x ht mm
Typ gross wt
Max gross wt
Rec offtake 20/1°C
246 x 345
246 x 490
318 x 585 (605
40.0 Kg (!)
* i.e. twice the output of a 3.9 Kg
11 Kg Flogas
305 x 550
305 x 540