Question posted 2009-01-17

Hello,

We are a US boat sailing in the South Pacific and have a propane-based cooking system. I need to know if we can fill it with Butane when in the French islands. I know the two gases are similar in nature, but will our tanks and regulator make the required change with the different gas?

Our stove is an ENO brand stove and states that both gases will work.

We use a single stage tank mount regulator and an Aluminum 10lb LPG tank, both of which were purchased at West Marine. I cannot find information anywhere about the required pressure reduction needed for such a change and if our existing equipment will suffice.

1) Can I use my current Propane tank and fill it with butane, and will the local country be able to fill it?

2) Will my current regulator make the switch, or do I need a new regulator and appropriate hoses?

Please help!

Thanks,

Seth & Elizabeth Hynes

Honeymoon, Lagoon 380

Noonsite Pacific regional editor – Luc Callebaut answers:

1) Yes, the same tank can be filled with either propane or butane. In the last 10 years, I have traveled between French Polynesia and Vanuatu. I was able to get my US type 20Lbs tanks filled anywhere (although I did hear recently that it might not be possible in New Caledonia and French Polynesia might have the same problem now). I suggest you email directly any marina or boatyard there and ask them.

It is also possible to get a local tank and use it to fill your tank by gravity. You will need a simple hose fitting to your tank and at the other end a fitting that connects with the local tank (get a 5′ hose with your US fitting already fitted on one end and use a hose clamp to clamp on any local fitting you might need on your travels). Note – that in many countries, the main filling station has adaptors to fill the cylinders with different valves.

2) Yes, your regulator and hose will work with either gas. Last year Vanuatu switched to propane and I suspect that all Pacific countries served by the same company – Origin Gas – will have a similar change.

If your tank is more than 10 years old, in Vanuatu they replace the valve and you are good for another 10 years (that is if your tank is in good shape, which was the case for my aluminum tanks).

If your stove makes states that both gases work, then you should have no problem. Although be aware that some equipment might not work as efficiently as the pressure is slightly different.

Further comment received 2010-01-18

Received From: Peter Thurley

Subject: are propane and butane interchangeable

Message:

I’ve just read the article and it’s fine but propane should not be put in a tank designed for butane as the propane is at a higher pressure. I’ve used both in my propane system with no noticeable difference, though I’m told the calorific value of butane is higher so burns hotter. A bottle of either lasts about the same time.

I’ll add that if you are going to sail in very cold weather, propane is necessary as butane doesn’t boil off at low temperatures.