On 11/16/2014 10:42 AM, Stephen wrote:
> On 16/11/2014 15:48, Thomas de Groot wrote:
>> On 16-11-2014 15:13, Stephen wrote:
>>> The heat is taken from the air and the hand that is holding it. You can
>>> feel the lighter getting cold and you can hear the butane rushing into
>>> the lighter. The sound will stop when the pressure has equalised and the
>>> lighter will continue to fill up.
>>>
>>
>> Such a long time since I stopped smoking that I only dimly remember
>> these things. The cold comes from the gas expanding, right? Same way as
>> a fridge.
>
> Correct.
>


Almost, but not fully.

The cold comes from the phase change from liquid to gas (It takes energy 
to evaporate the liquid, and the liquid will happily do so, because the 
equilibrium favors the gas phase (lower pressure on the cold side) If 
there is not enough pressure on the hot side (i.e. not enough coolant) 
to condense the gas to a liquid, the refrigeration is minimal to 
nonexistent.


... As for the rest of the conversation, it's fascinating; I think it's 
pressure difference that fills the lighter.

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