Title: AV-1 alarm valve.pdf
to the Seat Ring. If the volume of the air pockets is excessive, flow into the system can be momentarily reduced to nearly zero (once the air pockets are compressed) and the Waterway Clapper may close, causing flow to the alarms to be shutoff.After the Waterway Clapper has closed, sufficient water must flow out of the system before the Waterway Clapper will again open. A repetition of the above described condition is termed an intermittent alarm.Using a vent (which can also serve as an end-of-line Inspector’s Test Connection) piped from the top of a cross main or end of a branch line at the point most remote from the alarm valve, and filling the system slowly in accordance with the steps described in the Setting Procedure section, can pre- vent an excessive amount of air from being trapped.Installation