A AMM - AIR SUPPLY - DESCRIPTION AND OPERATION

Transcription

1 AIR SUPPLY - DESCRIPTION AND 1. General For an effective distribution, the potable water system is pressurized with an air pressure of psi ( bar). Compressed air is obtained from the following pneumatic system sources to meet the pressurization requirements: - Engine Bleed Air - Auxiliary Power Unit (APU) - Ground Compressed Air Supply Unit. To compensate any drop of pressure in the water tank(s) an auxiliary air compressor (21MD) is installed. The compressor is activated by pressure switch (22MD). Air pressure is indicated via pressure transmitter (20MA) on two pressure gages. One pressure gage (21MA) is installed on potable water service panel and the other on combi gage (22MA) at purser's panel (863VU). 2. Component Location (Ref. Fig. 001 ) (Ref. Fig. 002 ) FIN FUNCTIONAL DESIGNATION PANEL ZONE ACCESS DOOR ATA REF. 9MA 1OMA 20MA 21MA 22MA PUSHBUTTON - PUSH FOR IND SWITCH - DOOR MICRO TRANSMITTER - PRESSURE GAGE - PRESSURE GAGE - COMBI VALVE - SHUTTLE VALVE - CHECK VALVE - PRESSURE REDUCING/RELIEF FILTER - AIR 863VU 863VU BR BR (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) P.Blk EFFECTIVITY: Page 1 of 8

2 FIN FUNCTIONAL DESIGNATION PANEL ZONE ACCESS DOOR ATA REF. 1 2 PANEL - POTABLE WATER SERVICE PORT - GROUND PRESSURE SUPPLY BR BR 9MA 10MA 20MA 21MA 22MA 21MD 22MD PUSHBUTTON - PUSH FOR IND SWITCH - DOOR MICRO TRANSMITTER - PRESSURE GAGE - PRESSURE GAGE - COMBI COMPRESSOR - AIR SWITCH - PRESSURE VALVE - SHUTTLE VALVE - CHECK VALVE - CHECK VALVE - PRESSURE REDUCING/RELIEF FILTER - AIR FILTER - AIR FILTER - AIR PANEL - POTABLE WATER SERVICE PORT - GROUND PRESSURE SUPPLY 863VU 863VU BR BR BR BR (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) (Ref ) 3. Description The pressurized air supply system includes the following components: A. On Purser's Panel (863VU) - A pressure indicator on combi gage (22MA) - A pushbutton switch PUSH FOR IND (9MA) B. On Main Water Tank - A shuttle valve - An air filter - A check valve B. On Main Water Tank - A shuttle valve P.Blk EFFECTIVITY: Page 2 of 8

3 - Three air filters - Two check valves - A pressure switch (22MD) - A combined pressure reducing/relief valve - A pressure transmitter (20MA) C. On Potable Water Service Panel - A pressure gage (21MA) - A door microswitch (10MA) - A ground pressure supply port for ground servicing D. In Zone 132 between FR , STG 49 - Air Compressor (21MD) 4. Operation (Ref. Fig. 003 ) (Ref. Fig. 004 ) The compressed air, irrespective of the supply source, flows via shuttle valve, air filter, check valve and pressure reducing/relief valve to the water tank(s). The compressed air, except auxiliary compressor source, flows via shuttle valve, air filter, check valve and pressure reducing/relief valve to the water tank(s). The auxiliary compressor (21MD) supplies the water tank(s) with compressed air via a filter and a check valve. The shuttle valve directs pressurized air, either from the bleed air crossfeed line or from the ground compressed air supply line, to the air filter. Any impurities in the compressed air are filtered by the air filter. The pressure reducing/relief valve reduces the pressure from 44 psi (3.0 bar) to system working pressure of psi ( bar). P.Blk EFFECTIVITY: Page 3 of 8

4 The pressure relief valve opens when system pressure exceeds 34 ±2 psi (2.35 ±0.14 bar) and reseats at a pressure of 30 psi (2.07 bar). A check valve, installed between the air filter and pressure reducing/ relief valve prevents water tank air pressure from bleeding back into the charging system. The auxiliary compessor (21MD) is activated by pressure switch (22MD) when pressure in the water tank(s) drops below 22 psi (1.5 bar) and deactivates it when pressure reaches 25 psi (1.72 bar). In flight, air pressure is indicated on the purser's panel (863VU) by combi gage (22MA) when pushbutton switch PUSH FOR IND (9MA) is pressed. On ground, with power supply on and potable water service panel access door (BR) open, air pressure is indicated on both purser's and service panel pressure gages (22MA, 21MA). P.Blk EFFECTIVITY: Page 4 of 8

5 Figure 001 Figure 001. Component Location (Sheet 1) P.Blk EFFECTIVITY: Page 5 of 8

6 Figure 002 Figure 002. Component Location (Sheet 1) P.Blk EFFECTIVITY: Page 6 of 8

7 Figure 003 Figure 003. Electrical Schematic (Sheet 1) P.Blk EFFECTIVITY: Page 7 of 8

8 Figure 004 Figure 004. Electrical Schematic (Sheet 1) P.Blk EFFECTIVITY: Page 8 of 8