Following tools shall be arranged before starting the testing and commissioning of pre action system.
- Valve opening keys
- Screw drivers
- Smoke agent
- Digital multi meter
- Communication Devices
Pre-Commissioning Checks
Before commissioning the system the following shall be ensured:
- The system has been checked against the approved installation drawings.
- The pressure testing or the pipes arc completed.
- The installation or Deluge Valve Assembly, Isolation valves.
- Compressor, associated pipe works, and Control panel completed.
- The installations of pre Action/ water sprinklers are completed.
- The termination to all devices pressure switch, solenoid etc is completed.
- Cabling and interface connection to main line alarm panel is completed.
- Make sure the entire above test / installation is approved by consultant.
- Check and confirm that deluge valve and accessories are ready for putting the system in service.
- Confirm that the pressure control valve set to the system required pressure.
- Check that all sprinklers are free from obstructions.
- Confirm that check valves are installed at the correct flow direction.
Commissioning Procedure
Setting Procedure:
- Close the system main control valve, differential chamber supply control panel and if the system is equipped with dry pilot release, close the dry pilot air supply control valve.
- Operate the manual control station to assure that the deluge valve differential chamber is vented.
- Open the main drain valve and all auxiliary drains in the system piping. Check to see that the discharge of drainage water will not cause damage or result in dangerous conditions.
- After water ceases to drain close all auxiliary drains in the system piping.
- Clean out the strainer in the connection to the deluge valve differential chamber. Reassemble the strainer after cleaning.
- Remove the hand hole cover and then carefully clean the seating surface of the clapper arm and
the water seat disc. Verify that the retaining lever as well as the differential valve plunger assembly move freely to the left. - With your left hand holding the clapper arm and your right hand pushing the latch pawl, unlatch
the clapper arm and carefully lower the clapper arm into the set position with the nose of the
clapper arm under the retaining lever. - Reach into the hand hole opening and while holding onto the differential valve plunger rotate the differential valve plunger and pull it towards the retaining lever. As the differential valve disc seats against the differential valve seat within the differential valve housing some resistance to rotation should be felt to indicate adequate seating.
- Inspect the handhold cover gasket for breaks and replace the hand hole cover and its cover gasket. Tighten the hand hole cover bolts with a cross-draw sequence.
- Service the air dryer if applicablc in accordance with the manufacturers instructions.
- Reset the release system.
- Check and ensure the auto start air compressor was connected with permanent power supply and
the compressor was started immediately, when the system air pressure goes below 40 psi Pressure
and maintain it same.
Functional Test Procedure (Automatic Operation)
The functional test sequence oft he double interlock (Automatic) pre action system is as follows:
Step 1: The system is shown ready for operation.
Step 2: When the smoke detector gets activated cross zoned the smoke detector sends a signal to the pre-action control panel.
Step 3: The pre-action control panel turns into alarm condition and sends a signal to open the solenoid valve. Simultaneously FACP and BMS receives the fire signal (Trouble signal goes to the FACP/BMS at power failure, battery failure and low system pressure in the pre-action control panel) from pre action panel.
Step 3a: Immediately the control signal goes from FACP/BMS to lift control panel at the same time the lift will come down to respective default level within 90 sec., door will open and lift power supply will be shut off.
Step 3b: When the fire sets off a sprinkler pneumatic pressure drops in the dry pilot trim, the Actuator opens which permits water to flow through the drain. This will drain water from the diaphragm Chamber.
Step 4: The open Solenoid valve and dry pilot actuation will release water from the Diaphragm Chamber faster than it can be replenished through the drain restriction in the Automatic Shut-Off Valve.
Step 5: The rapid pressure drop in the Diaphragm Chamber forces the Diaphragm open, allowing air to come out of the sprinklers when the sprinkler bulb breaks open due to the temperature caused frorn fire.
Step 6: The rapid pressure drop in the Diaphragm Chamber forces the Diaphragm open allowing water to enter the system.
Step 7: Water flows through the system to the Water flow pressure alarm switch activating the alarm. Water passes through the trim to the Automatic Shut-off valve to close this valve. Once closed it will prevent the Diaphragm Chamber from becoming inadvertently “Re-Pressurized”, the Automatic Drain Valve is also closed.
Step 8: Water flows through the rest of the system allowing water to spray from the open sprinklers.
Step 9: After fire is under control, Main Control Valve is manually closed to cut out the water supply. The Diaphram chamber supply Valve is also closed.
Step 10: Then the Main Drain Valve, Alarm Test Valve and the System Drain Valve are opened to drain water from the system.
Step 11: Once the system stops discharging water, close all drains except the Main Drain Valve. Depress the plunger of the Automatic Drain Valve to verify that it is open and the system is drained.
Step 12: Reset the Manual and/or Electric actuation systems. Reset the Solenoid Valve. Clean the Y-strainer in the Diaphragm Chamber Supply connection trim.
Step 13: Open the Diaphragm Chamber Supply Valve so the Diaphragm Chamber can return to full pressure.
Step 14: The Diaphragm will completely close once the Diaphragm Chamber returns to full pressure.
Step 15: Close the Alarm Test Valve. Finally slowly open the main Supply Valve and close the Main Drain Valve once water begins to discharge from the drain.
Step 16: The system is then ready to return for beneficial use.
Functional Test Procedure (Manual Operation)
The functiona l test sequence of the DOUBLE INTERLOCK (Manual ) pre-action system is as follows:
- Release the water from the diaphragm by using manual actuator and release the air pressure through system drain valve confirms the Water flows through the system to the Water flow pressure Alarm Switch activating the alarm. Water passes through the trim to the Automatic Shut-off valve to close this valve. Once closed, it will prevent the Diaphragm Chamber from becoming inadvertently “Re-Pressurized”. The Automatic Drain Valve is also closed.
- Water flows through the rest of the system allowing water to spray from the open sprinklers or Nozzles.
- Repeat the steps 9 to 15 to confirm the step 16 in above section.
Dry Pilot Actuator Function
The function of the dry pilot actuator is as follows:
- When the dry pilot actuator is in service, the pilot line or sprinkler line pressure holds the diaphragm depressed and the disc seated against the water pressure from the differential chamber of the Deluge valve.
- Operation of a sprinkler relieves the air pressure from the diaphragm.The spring and water pressure from the differential chamber of the Deluge valve then combines to force the dry pilot open. which permits water to begin flowing through the 1/8 inch diameter holes located in the dry pilot wall.
- As the air pressure continues to decrease from 40psi, the flow out of the DP increases to a rate
which is greater than can be replenished through the restricted water supply to the differential chamber of the deluge valve, which in turn permits the deluge valve to open and allow a flow of water into the system piping.
Battery Autonomy Test
The pre action panel battery autonomy test was carried out for 24 hrs by removing the permanent AC power supply and keeps the panel alive by battery power.