Conecting a hob to bottled gas?

[Dave]

Hi All,

The Situation:    Our Kitchen is on the first floor.

The Plan:           Is to place the Gas bottle to supply the hob on the ground floor in the Utility room

The Reason:      The reason for this is to save us having to carry heavy bottled gas up the stairs.......

The Question:   If the distance between the gas bottle and the connection to the hob is around 3.5 metres, will there be sufficient pressure in a bottle to give a good enough pressure at the hob, or do I need to raise the bottle onto a platform in the Utility room?

thank you all in advance.

best regards

Dave in the Lot.[:)]

[Iceni]

Our gas bottle is down in the sous sol probably 2.5/3.0m from the hob and oven and we do not suffer any probs with low pressure.

John

not

[le bouffon]

Make sure that the jets on the hob are for the right gas,we bought a hob in Spain the other week,and I had to change the set up.

[Gastines]

Apart from the obvious,ie,the correct regulator and as pointed out ,the correct jets for bottled gas. IF you are running the gas feed through a wall or in your case through a floor? make sure you put another pipe around it where it goes through the floor/wall. This ensures no build-up of gas ,in the wall,if you get any damage or mice eating the pipe causing a minute leak.

Regards.

[powerdesal]

I suggest you run the majority of pipe in copper, not many

copper-eating mice as far as I know. A short flexi to the regulator and

similarly a short flexi to the hob. Its probably a good idea to fit an

isolating valve at the hob end of the copper before your flexi

connection. Only a suggestion of course.

Regards

[La Guerriere]

And don't forget you can get manifolds that couple two bottles together.

[powerdesal]

Jim,

Can you point me in the right direction for twin bottle manifolds? I

remember years ago seeing an auto-changeover twin manifold but cant

remember any makes etc.

Regards

[Gyn_Paul]

I have a pair of gas bottles outside the house then piped in 16mm copper the whole end and length of the building  (some 25 metres) then it feeds a multipoint and a tumble dryer and continues to the kitchen  to the cooker.  The only time you even notice the multipoint cutting in/going off is when the bottle is nearly empty.

I looked at the autochangeover thingys some years ago and decided they were too expensive : (something like £90 with connectors) however, every time I have to get out of the shower (dripping) and climb into a dressing gown (shivering) and go change a gas bottle (freezing) re-light the multipoint (frostbite) it seems cheap at twice the price!

p

[La Guerriere]

I have seen the two bottle manifolds in Bricomarche and Mr Bricolage, probably available in most GSB's.

[Jonzjob]

With bottled gas the regulator will be 'plugged' directly onto the bottle. If you are keeping te bottle inside the house it will normaly be Butain and the regulator is set to 28 millibars. The gas isn't suited to outside usse in the winter because it stops gassing, evaporation off of the top of the liquid gas, at sub zero temps. If the bottle is being kept outside it will normally be propain which stops gassing at -40 deg C. The regulator is set to 37 milibars and the gas gives a little higher calorific value than butain. Some say that propain should not be kept indoors, but the only difference is the calorific value. Where ever the bottles are kept it should be in a well vented place. The gases are heaver than air and will 'pool' in the lowest point of a room/storage area if there is a leak. I would NEVER keep a bottle in a sunken cellar because if there is a leak the celar willl fill with the gas and a spark [+o(]!!!!!!

It doesn't really matter how far your hob is from the bottle unless the pipe is very small or the hob is huge. The pressure won't drop enough to notice. In the U.K. we were on a 1000 litre propain tank at the bottom of our garden, about 100 foot+ away. The pressure was the same as the bottles we replaced and we ran all our cooking and central heating from it. Here in France the tank is a bit larger, but we still run our hob (not the oven here) and our under floor central heating with no problems.

As far as the auto change over valve is concerned, we had one before converting to the tank in the U.K. and I would recomend one to anyone. No more getting out of a suddenly cold shower. All you need to do is have a look at the indicator on the top of the change over valve every now and then and when it shows a red flag just turn the knob on the top to the full bottle and note to get a new bottle. If, after that, you finish up in a cold shower then there is NO help for you!!!

John.

[thunderhorse]

Your question only concerns pressure. At the end of the day you're talking about a distance of eleven feet. If the bottle was on the same level, would you consider it a problem? No.

Therefore your concern is the height element. How high a platform would you consider in the utility room? Pretty low, because you don't want to lift heavy gas bottles. Three feet max, which leaves eight feet + for a pressured gas bottle to push gas to a hob.

There are plenty of houses in France with gas bottles stacked outside, garage and sous-sol etc., and all the living accommodation above.

Don't understand the problem.

[powerdesal]

Jim,

Thanks for info, but what is/are "GSBs"

Regards

[La Guerriere]

GSB = french shorthand for "grandes surfaces de bricolage" - the big DIY establishments

[Thumper]

Jonzjob mentions the difference between butane and propane, and the tendency for propane to be stored outside while butane is permitted within the house. I always thought this was because propane was heavier than air and pooled (but was less likely to freeze outdoors in winter), whereas butane was lighter and, if there was a leak, would dissipate upwards and escape, thereby being less likely to cause an explosion. For that reason gas detectors for propane are fitted at floor level, while detectors for butane or mains gas can be higher up, even on the ceiling. Is this wrong then?

I assume the regulations in France are similar to those in the UK, whereby only certified fitters are supposed to install pipework for gas? Despite this, fittings etc seem very easy to obtain in France, at almost any bricolage or hypermarket, which seems to contrast strongly with the situation in the UK, where only specialist suppliers stock anything except the most basic materials. 

[Gyn_Paul]

I was always lead to believe they were BOTH heavier than air.  Occasionally you read of an explosion on a boat because a leak has pooled in the bilges and then ignited. Surely that would be Butane?

A not terribly scientific test I've just conduced (fill a polythene freezer bag with butane and let it go and watch it fall to the ground rather faster than it seemed to do with just air in it) would lead me to believe that it IS heavier than air. Perhaps propane is heavier than butane, but they are both heavier than air ??

As for why the one is allowed indoors and the other isn't I cannot say. Just that my French plumbing book distinctly says that le propan est strictement interdit a l'interieur.

Another oddity: English regulators - from memory - have opposite threads for butane and propane thus making it impossible to put the wrong regulators on the wrong bottles. Here in La F., they both sport a wrongway thread. I have inadvertently put propane bottles on a butane regulator and not noticed the difference either in flame height or performance. Indeed I'm currently soldering central heating pipes using a propane blowtorch on a butane bottle and it's performing perfectly satisfactorally. Do we indeed need 2 different mbar regulators at all?

p

[Thumper]

Having now checked, I discover you are right. They are both heavier than air. Propane (C₃H₈) has a molecular weight of 44 g/mol, and butane (C₄H₁₀) has a molecular weight of 58 g/mol, so they will both sink. Mains gas is a mixture, not a compound, and its composition varies. Typically, however, it is about 95% methane (CH₄, molecular weight 16 g/mol) with the rest comprising ethane, propane and carbon dioxide, plus an odorizer to make it smell. It will tend to rise, although not as fast as something like helium - hence domestic detectors in main-gas houses being located higher up.

My experience is with boats, where we have always used propane. I don't think I've ever come across butane being used on a boat. We fit gas detectors in the bottom of cupboards and down in the bilges. We also use so-called "pig" connectors on propane bottles, which are male-orientated and cannot be fitted to a butane bottle, which has a female connector. The bottles are always stored external to the cabin, above the waterline so that drain holes can be included for waste gas to escape overboard.

Apparently, butane is "less volatile" than propane, which may be why it is preferred for indoor applications, but where the gas can be piped in from outside, propane is preferred because it remains gaseous at lower temperatures . Both are naturally odorless, and additives are included during the refining process to make them smelly.

[powerdesal]

Thanks for the GSB translation.

Regards

[Gyn_Paul]

[quote user="Thumper"]

Apparently, butane is "less volatile" than propane, which may be why it is preferred for indoor applications, but where the gas can be piped in from outside, propane is preferred because it remains gaseous at lower temperatures . Both are naturally odorless, and additives are included during the refining process to make them smelly.

[/quote]

Certainly butane - if you are drawing off a large quantity; for a multipoint water heater for example - starts to give up on you once the temperature is pushing 2C or lower.

I'm old enough to have been at school in Liverpool during the change-over from coal gas to Natural gas. We science students were very dissapointed to discover that a bin bag filled with this new natural gas was no substitute for the old hydrogen-based coal gas. No longer could we float them out of the lab window with a burning fuse attached and watch them rise to a couple of hundred feet before flaming out with a 'whoosh'.

[le bouffon]

We always tried to use camping gas on our yacht as it is should be standard through the EU,never was.We used propane(it is much better at low temps) even in north africa(during the winter)as you can only wait so long for the morning cup of cofffee.