On Sun, 20 Aug 2006 22:01:51 UTC, "Alan Holmes"
wrote:


"Graham" wrote in message ...
What are the advantages and disadvantages of gate valves and full-bore
Ball valves for mains water, and isolating parts of a CH system.

A ball valve is to set the level of water in a header tank, a gate valve is
use to shut off or allow a flow of water.

Two completely different uses.

Not the ball valve he means. The construction is similar to the small
service valves one should fit in the feed to things. A rotating
spherical shell in a spherical chamber, with holes that rotate in line
with the pipes to open, and reverse to close.

To answer the OP, although others will know more...ball valves (in this
context) give full flow, as do gate valves. Only ball valves give no
flow; gate valves (a) leak a bit and (b) tend to jam. They're also much
slower to operate.

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