Any butan gas for my Weller Pyropen?

[Mr Simpleton]

I was discussing butan gas driven soldering pens with a friend when he mentioned that his Weller Pyropen had a problem, and when requested it fixed under warranty, the Weller rep said: "You have been used lighter gas, this will destroy the catalyser"

Does standard butan "lighter gas " have impurities that kills the catalyser, or is this pure bollocks? Or is any butan gas good enough? Or do ligher gas sometimes use propane? Would this kill the soldering pen?

Cheers

[BradC]

Cheap butane can sometimes contain impurities. I run my gas axe on iso-butane. Marginally higher pressure, but I can get it clean and un-stenched.

Lighter gas has often has mercaptans in it for the odour. They are ok when burned in a clean flame, but in a catalysed burner they could decompose diffently I suppose. I've also seen some fairly non-volatile oils in cheap butane before.

[Ian.M]

Lighter gas *can* contain impurities that will kill the catalyst, but that's fairly unlikely.  They all seem to use the same basic technology - a preheated high temperature ceramic wool, coated with a very thin film of platinum or other rare metal catalyst.  Any salts are bad news - as they can attack the ceramic, and I believe Sulpher can also poison the catalyst so I wouldn't recommend lighting one with a match.

Although I don't have a Weller Pyropen, I have been using the same catalyst heads in a couple of gas irons for years using whatever lighter gas has been cheapest - one's a Portasol, and that has a protective cap, the other's a combo kit - litlle pencil blowtorch with interchangable heads for varios tasks including catalytic heads for hot 'air' and soldering.  The first catalytic soldering head for that lasted me about a month - then I figured out it was a contamination issue, and made a little waxed paper sleeve to slip over the soldering head vents when cold to keep dirt out.  That was about 25 years ago.   I've had more trouble keeping the filler valve and control valve in good condition than with that catalyst.

However low grade gas can contain excess tar - which gunks up the valve and pinhole jet.  IIRC I was successful blowing out the tank with fresh gas to dilute the tar residue then soaking the jet in solvent to soften the tar then bleeding off gas jet down with no head on till there was no more traces of tar from the jet.

[Mr Simpleton]

Great, thanks for the answer. So it may be contamination, but not from the gas but when in storage! And the oil/tar issues is noted too.

Will pass on the information and also make sure I do protect my Weller from the harsh environment

Cheers