In article , Harry Bloomfield
writes
rick used his keyboard to write :
Yet the facts seem to be:

Propane = 96 Megajoules of energy per cubic metre.

Butane = 126 Megajoules of energy per cubic metre (far more than propane)

There is more heat / better value to be had from butane. The only
benefit of propane is that it turns to gas at temperatures below
freezing. The two different regulators are of a different pressure of
output, so the results at the burner are the same.

Some modern caravan systems use a single, bulkhead mounted regulator
I think they All do. EU regulations and all that.
which is a compromise between the two pressures needed and the gas
appliances designed to work reasonably well with either pressure.

--
bert