Question about gas heaters

[Domdom]

heres one for you patio gas is dearer than propane to fill. both the same weight . for what reason i already know the answer

Patio gas is a mix of propane and butane but that’s not really a valid reason for why it costs more. I used to drive the bulk tankers out of Immingham back in the 90’s and back then it was a few pence a litre. Effectively it was considered a waste product.

LPG for cars (propane) had road fuel duty applied and it was still below 30p a litre after all the transport costs and retailer margins. At the same time the 47kg cylinders (about 95 litres) were £60, so about double. A lot has to do with owning, maintaining and managing a huge inventory of cylinders.

Butane was always more cos of the clip on regulator and the time taken to fill them. It has a much lower boiling point and a lower calorific value which also makes it a slower fill, needs higher differential pressure to force it in. Propane fills much quicker cos of the hole size, but there was less demand for butane anyway so the poor guy in the filling shed had more work to do. Patio gas has a similar clip on regulator and also has to be pre-mixed which is another step in the process. It all adds cost.

Over here there is only 1 type, with a clip on regulator. Nothing as large as the 47kg cylinders in the UK, the biggest is 13kg. The only time propane is used is on the forecourt where LPG cars can fill up as they need the higher calorific value. Pure Butane is not really needed, the main benefit being the lower boiling point, but cylinders don’t ice up in this climate. That’s the main issue with Propane in cold and damp climates, the cylinder ices up and the gas won’t come out. It has to effectively boil from being a liquid to become a gas and IIRC propane boils just below the freezing point of water. If you’re caravanning in freezing climates you definitely want butane LOL.

And yes, even knowing what I do about the various LPG products, I still never knew why some heater are OK indoors and some aren’t. Live and learn. Very interesting info about heaters here, cheers lads.

 

[Misterg]

That’s the main issue with Propane in cold and damp climates, the cylinder ices up and the gas won’t come out. It has to effectively boil from being a liquid to become a gas and IIRC propane boils just below the freezing point of water. If you’re caravanning in freezing climates you definitely want butane LOL.

It's the other way around: you want propane for the cold - butane boils at ~0°C so loses pressure in frosty weather.

 

[Domdom]

Ah yes, that's what I meant - ish. I just remembered them the wrong way round.

 

[dave h 2]

I was under the impression (maybe wrongly) that the indoor version was premixed combustion and the outdoor was diffusion. The difference being the former mixes oxygen with the gas before combustion and the latter takes as much oxygen as the combustion process requires. Like a school Bunsen burner when the air collar is adjusted.

And I was under the impression that the Calor Super Ser three panel heaters were catalytic

 

[Kayos]

And I was under the impression that the Calor Super Ser three panel heaters were catalytic

A catalytic gas fire will have a sealed glass front