One for the chemists

There's NOx in there - maybe not nitric, but nitrous.

Also Sulphuric due to sulphur content of 5.5 mg/m3. This includes the 4.9 mg/m3 of sulphur in the odourant (mercaptan) added to gas for safety reasons.

Yes, I know! I've seen similar rankings, and I doubt there are many left as a result.

Mine still looks like new inside due to me servicing/maintaining it very carefully, but they have many common failures which if not caught quickly, will write it off in a short time. I did grab one from another reader of this forum which British Gas had maintained but then condemmed. That was due to leaving the internal bleed valve open, and the resulting leak corroded through the case. However, that was after a string of failures which meant much of the internal parts had been recently replaced, so it gives me some spares stock.

Yes. I don't think CO2 on its own can give a solution with a pH as low as those seen for condensates.

The oxides of nitrogen are many and various, not all are soluble in water, and of those that are, not all give acidic solutions, but for the ones that do, it all ends up as nitric acid eventually, IIRC.

I wonder what happened to the 2 that another poster installed in his church ?. Wasn't he the ex BCO or something ?, don't seem to hear from him much these days.

Since then it's occurred to me that may be a bit of sulphur in there too

- sulphur(ous|ic) acid. I'm surprised there's much NOx though. It isn't that hot a burn.

Andy

About 1950C.

NT

Agreed, see

Also, NOx content of gas flames rises rapidly above 2800F (1534C)

I sit corrected. So how come petrol engines don't produce much NOx? Is it the stoichiometric mixture? And aren't boilers supposed to be close to that these days too?

Andy

Catalytic converters.

Sort of. Cats certainly used to need the combustion mixture to be stochiometric before they would function properly.

Yes, but they don't have cats.

Tim