R **ON A/C 401-499,
R D. Bypass Valve
R (Ref. Fig. 008C)
R The bypass valve 10HH (30HH) is a light alloy 2.5-inch butterfly valve.
R It is located in the duct downstream of the primary heat exchanger and
R splits the hot airflow between the ACM and a bypass (which goes to the
R turbine outlet). The bypass valve gets a signal from the ACSC 47HH (57HH)
R (primary and secondary computer) to modulate the hot airflow. This
R controls the water extractor outlet temperature, thus the pack outlet
R temperature. The bypass valve 10HH (30HH) consists of an actuator
R assembly and a valve body assembly. They are bolted together and
R internally connected.
R A butterfly valve on a central shaft is driven by a stepper motor through
R reduction gears which have mechanical end stops. A cam (installed on the
R shaft) operates a limit switches which signals the fully closed position
R to the ACSC 47HH (57HH) secondary computer. Step counting signals the
R primary and secondary computers for indication. The limit switch signals
R the secondary computer for BITE. A manual override and visual position
R indicator device is installed on the bottom of the shaft.
R **ON A/C 001-049, 051-099, 101-149, 151-199, 201-299, 301-399,
E. Anti-ice Valve
(Ref. Fig. 009)
In each air conditioning pack 10HM (11HM), the anti-ice valve 17HH (37HH)
is located in a duct between the upstream side of the primary heat
exchanger and the turbine outlet. In normal pack operation the purpose of
the anti-ice valve is to prevent ice blockage across the condenser. If
the pack controller 7HH (27HH) is unable to control the bypass valve 10HH
(30HH) the anti-ice valve is signalled to pneumatically control the pack
outlet temperature to 15 DEG.C (59.00 DEG.F).
R 1EFF : ALL 1 21-61-00Page 79 1 1 Aug 01/05 1 1 1CES 1
Bypass Valve 10HH, 30HH - Schematic
Figure 008A (SHEET 1)
R 1EFF : 004-049, 055-099, 101-105, 151-158, 1 21-61-00Page 80 1201-210, 1May 01/05 1 1 1CES 1
Bypass Valve 10HH, 30HH - Schematic
Figure 008A (SHEET 2)
R 1EFF : 004-049, 055-099, 101-105, 151-158, 1 21-61-00Page 81 1201-210, 1May 01/05 1 1 1CES 1
Bypass Valve 10HH, 30HH - Schematic R Figure 008B
R 1EFF : 106-149, 159-199, 211-299, 301-399, 1 21-61-00Page 82 1 1 Aug 01/05 1 1 1CES 1
Bypass Valve 10HH, 30HH - Schematic
R Figure 008C
R 1EFF : 401-499, 1 21-61-00 Page 83
1 1 Aug 01/05
1 1
1CES 1
Anti-Ice Valve 17HH, 37HH - Schematic
Figure 009
R 1EFF : 001-049, 051-099, 101-149, 151-199, 1 21-61-00Page 84 1201-299, 301-399, 1Aug 01/05 1 1 1CES 1 Muscle pressure to activate the valve is drawn through a filter (8) through a tapping at the upstream end of the valve. Without muscle pressure the valve remains closed because of the action of a spring (7). In normal pack operation, the solenoid (10) is energized opening the vent valve. When muscle pressure is applied it is immediately vented and the valve remains closed. The valve stops the build-up of ice across the condenser using a differential pressure regulator (1). This differential pressure regulator opens the valve and deliver hot air to the condenser. Port (4) senses condenser inlet high-pressure and port (2) senses condenser outlet high-pressure. When ice builds up along the flow path through the condenser the pressure drop increases rapidly. The differential pressure between the ports (4) and (2) increases. This opens the poppet valve (6) which allows a high flow of muscle pressure into the Pneumatic actuator, which opens the anti-ice valve. The vent restrictor 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：A320飞机维护手册 AMM AIR CONDITIONING 空调 4(155)
