On Sat, 10 Jan 2004 05:56:03 GMT, "Toolbert"
wrote:

"Tbone" wrote in message
.. .

Don't kid yourself! After 24 years of experience in commercial high
rise const. If one head goes off the pressure surge will almost always
set off other heads in that general area.
Electronic areas should be isolated with a halogene (sp) system.

Tbone

There are (at least) two types of sprinkler systems.

The normal home / cheap residential style is as Gunner describes - simple
municipal water pressure, the heads go off individually as exposed to heat.

The commercial / high rise type has a pressure drop sensor and a booster
pump, it is designed to detect the drop of a single (wet or dry) head
opening in a zone, after which it blasts the entire zone open with a
pressure surge. The control system alone costs as much as a condo, so
don't expect to find that type in a home shop.

Bob

Yup.

Gunner

"Gun Control, the theory that a 110lb grandmother should
fist fight a 250lb 19yr old criminal"