Sprinkler pre action system
Sprinkler pre action system
(OP)
Is a sprinkler action system where
1) The preaction valve opens and the the pipe fill with water only when a smoke head is activated and a sprinkler head breaks (detected thro' loss of compressed air pressure)
or
2) the pre action valve open and the pie fill with water when a smoke head is activate only
2) If 2 is the answer does this mean I have to drain the system everytime there is a false alarm?
is it 1 or 2....???
1) The preaction valve opens and the the pipe fill with water only when a smoke head is activated and a sprinkler head breaks (detected thro' loss of compressed air pressure)
or
2) the pre action valve open and the pie fill with water when a smoke head is activate only
2) If 2 is the answer does this mean I have to drain the system everytime there is a false alarm?
is it 1 or 2....???





RE: Sprinkler pre action system
Get used to draining it.
Good on ya,
Goober Dave
RE: Sprinkler pre action system
RE: Sprinkler pre action system
Single interlock floods the pipe when the smoke detector alarms. This is the one that you have to drain and dry the pipework out before rearming.
Double interlock requires both the alarm and a broken head before the valve opens.
RE: Sprinkler pre action system
Does the double interlock require compressed air and a pressure switch, or other means of sensing sprinkler head open?
Good on ya,
Goober Dave
RE: Sprinkler pre action system
RE: Sprinkler pre action system
'Trim' being the alarm valve, check valve, indicating valve, flow switch, solenoid, pressure switch etc.
Corrosion can be nasty of the pipework isn't treated and dried properly between activation, and you could get leaks. Double is preferred in critical, pharma and the like for this reason, but some authorities don't like the delay you get between the detector/head going off and water getting to the head.
You need to locate the riser and trim close to the protected space.