On 19/07/2011 19:52, Clive wrote:
In message
,
harry writes
The feedwater temperature is between a rock and a hard place. Cooler
is better for the pumps.
But hotter is better for boiler efficiency and dearation of the makeup
water.
The boiler feedwater tank needs to be as high as possible to minimise
possible pump cavitation.
I'm following the mention of the Gifford injector which has no moving
parts and no cavitation.

.... but which requires cold water, since the latent heat of the steam
provides most of the pumping power, so the steam has to condense in the
injector for it to work.

--
Jeremy Double {real address, include nospam}
Rail and transport photos at
http://www.flickr.com/photos/jmdoubl...7603834894248/