On 26/05/2017 21:25, rick wrote:
OK .. at a basic caravanning level 0 Propane is used for cold weather at
Butane the rest of the year.

Fully understand Butane has performance drop off with temp.


I jut bought a new gas BBQ ... it came with a 75mBar Propane Regulator
.....
Now temporarily I just stuck on a Butane regulator and connected to an
existing Butane bottle.

My question is will I get higher heat output performance if I use Propane ?
Read on several forums -= Propane burns hotter

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)

However Propane regulators feed a higher rate or gas to compensate.


So is it worth me changing to Propane for more heat?

Flow-rate is also important. When running a water heater from bottled
gas (running a shower), it was specified to run on propane (37mbar) or
butane (28mbar). It was also specified that a single propane bottle was
sufficient, but if butane was used, two must be used in parallel. The
reason was (and we proved this practically) that the high flow rate (and
hence high quantities of gas vaporising) cooled the bottle and if a
single butane bottle was used, the temperature would drop so low that it
would cease to vaporise - dual bottles halved the rate from each and
kept them warm enough, while propane can vaporise at a lower temperature
anyway.

During the winter, only propane would work due to the lower ambient
temperature.

SteveW