Gas Regulations

[Anthony_374236783]

Can anyone point me to the regulation which states you can not have both Propane and Butane on the new 30mb regulator sysem on a 2005 van.

or

Give technical reason that can be produced from a competent source.

Thanks

 

[rayc]

Anthony, you can use either Propane or Butane with the 30mb system. You do of course need the appropriate high pressure hose from the bottle to the regulator.

 

[Anthony_374236783]

Ray. Thanks for your reply. However I appear not to have been clear in my original question in that can BOTH types of gas be connected at same time? I thought I read an article some time past when the 30mb regulator arrived on the scene, which suggested this could be done ?

 

[Saladdodger]

Sorry Anthony but you still are not very clear. Are you asking if it is possible to have a Propane cylinder and a Butane Cylinder and have them both connected to your 30mb regulator at the same time. Is that your intention and if so, I can't help but wonder why?

 

[rob_jax]

Anthony,

The answer is both yes and no:

If you have the "old" gas system with bottle mounted regulators and low pressure tubing connecting to, say a Gaslow manual change-over valve, then yes.

If you have the "new" gas system with a single bulkhead mounted regulator, two high pressure pig-tails, and something like a GasLow T piece or change-over, then I'd say no.

In the first example, the worst that could happen from user mismanagement is that the gas going to the van is a blend of low pressure propane and butane at 30 milliBar (0.5 psig) - so it would actually be similar to you using LPG (natural mix of propane and butane)

In the second example, the worst that could happen is that both bottles become interconnected at high pressure - in this case the butane bottle typically has an internal pressure of 4 bar (60 psig) and the propane bottle has a pressure of 14 bar (200 psig) - and this time the propane bottle would potentially over-pressurise the butane bottle.

There are safety features in the T piece connectors and pig-tails to stop this happening, but it's best to avoid this possibility if you have the high pressure system.

Robert

 

[ProfJohnL]

Hello Anthony,

DON'T DO IT!

I cannot fault Robert's analysis of the practical issues, but technically I am confident that your proposal would be deemed illegal.

I no longer have access to the GS(I&U)Regs having retired from the business, but I do recall that the regs are written in a prescriptive manner, and thus any thing that is omitted is considered contrary to the regulations.

Thus the fact that duel gas type installations are not described, would be considered to mean they are not acceptable.

The problem with 2005 type system is that high-pressure gas direct from the bottle is fed to the common regulator. Thus it is possible for pressure from one bottle to cause gas to move to the lower pressure bottle. It is definitely illegal to allow or to cause a butane bottle to be filled with propane or vici-verca.

Robert has already mentioned the safety valves. These are set to different pressures to match the gas type. Butane having a lower vapour pressure blows off at a much lower pressure than the Propane one, thus a butane bottle operating a propane pressures is likely to discharge the excess pressure under relatively low temperatures.