Butane to Propane for Domestic Hob

[billy10]

Hi Guys ,

               Another poser from billy10, I have a feeling gluestick will know somethingabout this, here goes, my hob at the house in dept 36 is currently run from a butane (blue)bottle , it has one valve that screws directly into the top . It burns with a blue flame at the bottom but goes to an orange flame at the top and consequently makes the pots very sooty, I am told it is OK.  However my hob is also jetted so it will burn propane which I am told will burn hotter and will not soot up the pots , but a frien d who has recently had propane installed says that he has two valves , one on top of cylinder and another one in line  and maintains it is part of the European directive to have these two valves , anyone know anything about it and what do I have to do to cajhange over to Propane (red bottle) gas, to be within the law

Thanks all

Billy10

Incidentally gluestick , I managed to get a registered installer to do my central heating for the price I wanted which in the end turned out at 5000 euros lower than the two quotes I got, I think it is down to " brit adjustment" just goes to show .

 

[Gyn_Paul]

If all the burners are sporting yellow-topped flames then there is something amis with the air/gas mixture. Either the pressure the gas is being supplied to the burners is wrong, or the amount of air being mixed with the gas is wrong.

Hobs come with 2 sets of injectors for each burner. they are usualy fitted with the injectors for town gas, with the second set on a little card. This second set works for butane and propane. The difference in thermal properties of the gas being allowed for by delivering propane at a different pressure to butane. Hence the need for a different regulator for each type of gas.

A few possibilities:  -

Either the burners have still got the town gas injectors in them, or (more likely) you have a bottle of butane running through a propane regulator. There is a third possibility which is that the bore of the pipe from regulator to hob is too small for the distance, thus reducing the delivery pressure. 12mm will do for a couple of metres, 14mm for up to about  5 or 6 m, further than that use 16mm.

So first off I would recommend a close inspection of the regulator to see what it says and report back.

However,  having said all that, some older hobs and cookers are just plain crap and no amount of changing regulators or adjusting of flow screws will ever get rid of the yellow flame completely !

On your query about the second valve or regulator...

Where the gas bottle is fitted remotely from the appliance it is a requirement - I understand - for a detante to be installed near the appliance. This is a thingy which looks like a wall-mounted regulator. You turn a spring-loaded knob thru 90 degrees and it locks, allowing the gas to flow. When the bottle runs out and the gas pressure drops, it unlocks and clicks closed again. Once the pressure is restored you need to turn it thru 90 degrees again to get the gas to flow again. The idea is to prevent you changing an empty gas bottle for a full one, turning it on and forgetting the oven was turned on, thus filling the house with gas and blowing yourself up !

paul

[billy10]

Thanks Paul .

Unfortunately I am not in France now until September , but when I go over I will take a close look at the regulator on the bottle and see what it says , The bottle is located only 1 metre from the hob , so the 12mm pipe should be OK , Do you need the other valve if only the hob is using propane ??? If so I presume I could get one at Brico or somewhere similar and just fit it in line .

Regards

 

Billy10

[Gyn_Paul]

Is the gas bottle inside or outside? (I'm assuming the hob is inside !)

p

[Gluestick]

Glad you sorted out your heating, billy10; nice to learn about people saving money!

Not much I can add, here, in fact, as GP has pretty much covered it.

Propane has to be stored outside the house. The gas feed from the bottle must use the safety device as GP states. BTW, propane is fine outside: butane, however, will freeze.

On mixture: as GP has already stated, if the mixture of gas and air is correct, then the flame will burn blue. A yellow, sooty flame indicates incomplete combustion: the yellow tinged flame shows that there is unburnt hydrocarbon. Combustion is set by firstly the inlet jet and secondly by the (normally) rotating sleeve on each individual burner inlet. If you look under the hob (or indeed, any cooker) you will see a steel (normally) pipe running to each burner assembly. The gas inlet has a separate jet and the rotating sleeve. This where the gas and air mix.So if you like, it's the mixing chamber.

If you remember bunsen burners from the stinks lab at school, you rotated a sleeve for a blue flame: close the sleeve and the bunsen burned yellow. This is because the flame is taking oxygen from the air for combustion, rather than the air and gas mixing earlier in the feed pipe.

The mixing chamber ('cos that's what it is) also creates a sort of forced draft effect: same as a gas blowlamp; it is the air and gas being forced into the burning area, by a form of venturi, which is why blowlamps roar!

If the jet is incorrect, then you will have all sorts of problems. Once you've cracked the jet problem, then finally adjust the rotating sleeve for an optimal (blue) flame at the full-on position and a perfect flame in the simmer position. Like most things in life it is a compromise!

BTW: it has probably not been cooking very well, either, as the heat output will be very low with a yellow flame.

 

[Rob Roy]

"Either the burners have still got the town gas injectors in them, or (more likely) you have a bottle of butane running through a propane regulator. "

Three different people we know here had town gas injectors on their hobs (running bottled gas) and didn't know it until we suggested they check. They were all having exactly the problems Billy10 is describing re flame colour and sooty pots.

[Brilec]

[quote user="Rob Roy"]

"Either the burners have still got the town gas injectors in them, or (more likely) you have a bottle of butane running through a propane regulator. "

[/quote]

I thought that the bottles had different screw fittings so that propane and butane could not be mixed. (Propane female, butane male).

[Anton Redman]

[quote user="Brilec"][quote user="Rob Roy"]

"Either the burners have still got the town gas injectors in them, or (more likely) you have a bottle of butane running through a propane regulator. "

[/quote]

I thought that the bottles had different screw fittings so that propane and butane could not be mixed. (Propane female, butane male).

[/quote]

No when you buy you receive a plastic envelope with the other type of burner in them if you are very lucky it has a label which says which type of gas they are for. The fittings are set up so that one of the pair runs anti ( AKA counter) clockwise  so when you tighten one end you do not inadvertantly loosen the other. (AGH Catherine Cookson repeat has finished downstairs so I am being what I am doing awake at this time of the night which is a bit rich as I am waiting for Isabel to come to bed)

[Rob Roy]

[quote user="Brilec"][quote user="Rob Roy"]

"Either the burners have still got the town gas injectors in them, or (more likely) you have a bottle of butane running through a propane regulator. "

[/quote]

I thought that the bottles had different screw fittings so that propane and butane could not be mixed. (Propane female, butane male).

[/quote]

Sorry, I should have made clear the quote in blue was from Glyn_Paul, not from me. I was only commenting on our own experiences with friends, and what happened to us with a 2nd hand cooker (bought from the Troc) when we first arrived in France 5 yrs ago.

[Gyn_Paul]

No, standard French 13 kg gas bottles have the same wrong-way thread for the regulators regardless of whether they are for butane or propane. In our seaside house there is a cooker in the kitchen fed from a gas bottle just outside the kitchen door. I can't remember which type of regulator it has on it, but I do know we run butane on it in the summer, and propane in the winter. Can't seem to see any difference in the appearance of the flame when changed from one to the other.  Maybe the contents are a mixture these days...

p

[Dick Smith]

Interesting point, Paul. When I changed our cooker gas bottle this week I noticed that the old bottle had a blue label and the new one has red. Is that significant, does anyone know? I can't see or feel any difference when cooking.

[Gluestick]

I'm pretty sure, Dick that both Propane and Butane bottles have an identical thread.

I have been searching, for quite some time, for a "Dumpy" bottle of propane with the standard fixture. I want this for my blowlamp! So, in my naive way, I bought a French manifold fitting (for both Propane and Butane) from Mr Bricolage, took it back to the UK and modified a UKworkshop  fully adjustable regulator to fit and voila, I thought!

But no, it seems! I even bought a dumpy bottle, similar to my UK propane bottles (I've more than one UK bottle, in fact, since there are now competitive suppliers and the Jobsworth mindset swings into gear when one wants to swap them!). However once I stripped the sexy plastic packing off the new sparkling yellow French bottle, it has a sort of bayonet fitting. Took it back to swop and my friendly assistant at Champion instantly banged a new regulator on - for gas stoves etc! And I can't remove the S*****g thing! And the gas trickles out now and is non-adjustable. Ideal for boiling oeufes, but totally useless for sweating pipes!

So me blowlamps's fine, all provided I am happy (Not!) to lug a great big bottle around with me!

It would seem that competitive French gas companies paint their bottles all different sorts of colours, too, just to confuse us!

Thus far, I've seen them red, blue, green, yellow and a sort of metallic blue, too.

 

[Gyn_Paul]

[quote user="Dick Smith"]Interesting point, Paul. When I changed our cooker gas bottle this week I noticed that the old bottle had a blue label and the new one has red. Is that significant, does anyone know? I can't see or feel any difference when cooking.

[/quote]

What make are they Dick ?

p

[Fridgeman]

Hi All

Getting back to the original question, on some cookers there are adjusters in the end of the gas regulator shafts, you need to remove the regulator knobs and you will see a hole in the end of the shaft, you will need a long thin screwdriver pushed down the hole to adjust the flame height.

Hope this helps

Bonne chance