A. By blowing the water out at a low pressure of steam and after cooling off wash out and scrape the inside, removing all scale and sediment.
Q. How do you blow off your boiler?
A. By means of a blow-off valve situated at the bottom part of the boiler.
Q. When should a boiler be blown off?
A. When the steam pressure entirely disappears and the water is at boiling point, if boiler is set in brick work.
Q. Why not blow off under a full head of steam?
A. Because when blown off under pressure there is heat enough remaining in the shell and flues to bake the scale upon the interior, thus rendering it exceedingly difficult to remove.
Q. In what condition is the scale after blowing off at low pressure.
A. Some may be baked hard and attached to the flues and shell, but the greater part will be soft and slushy so that it can be easily removed.