From Glyn Hughes
How dare you poke fun at our noble profession
(Feedback, 5 February). An
“anti-gravity check valve” is a device well-known to heating engineers. It is
used to prevent dense cold water moving under gravity to displace less dense hot
water elsewhere in a heating system—an effect which is always referred to
in the trade simply as “gravity”.
Really, you mustn’t make fun of things you don’t understand. Next you’ll be
smirking at our “cocks”, “nipples”, “balls” and “male” and “female” fittings.
Admittedly, it does take some explaining to the average 16-year-old apprentice
where the “2-inch iron cock” or “22-millimetre bleeding nipple” get their names,
but anti-gravity valves are probably the least funny thing in the job.
glynhughes@btinternet.com
