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dennis@home dennis@home is offline
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Default Welding cast iron



"harry" wrote in message
...
On Jul 19, 10:39 am, Clive wrote:
In message
,
Andy Dingley writes Whilst the Giffard injector
stops working with
hot water, heat isn't a big problem for pumps.


Indeed, the colder the water the better the feed and ease of operation.
--
Clive


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.


Cavitation can't have been much of a problem or they would have used a two
stage pump to increase the head in the problem area.