(f)
Ejector: (Figure 1) The ejector is located below the cabin floor between fuselagestations 151.30 and 162.60. The ejector provides a vacuum sourceto operate all gyros.
(g)
Deicer Valves: (Figure 1) The deicer valvesare located below the cabin floor betweenfuselagestations 151.30 and
162.60.Onevalve is used for wing boots, the other for tail boots. The valves, normally closed, providea vacuum through an integral ejector, holdingdeicerboots down. When the deicer timeris energized, the solenoid valve onthe deicer valve opens and allows pressurized air to inflate the boots. When the solenoidis de-energized, from the deicer boots is
pressure
dumped and vacuum is applied.
(h)
PressureSwitches: (Figure 1) Thepressureswitchesindicateboot inflation to the pilot, and when the boot pressure reaches 15± 1 psig, the applicable switch closes. One pressure switchis located in the left wing leadingedge at wing station 97.50 and is used for wing boots. The second switch is located in the tail section at fuselage station321.00 and is used for the tail surface boots. The switches turnon indicator lightsat the top of the copilot'scircuit breaker panel to indicate proper operationof the deice system.
(i)
CheckValve: (Figure 1) The check valve is located in the cockpit, behindthe left side of the instrument panelat fuselagestation 66.50. The check valve prevents reverseflow from the vacuumlineto gyros.
EFFECTIVITY:
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36-10-00 PAGE
Jan 1
10/90
PIPER AIRCRAFT
PA-42-720(AdvancedTrainer)
MAINTENANCEMANUAL
A. Distribution (continued)
1
2
1.
2.
3.
4.
5.
6.
7.
8.
9.
Ports
Door Seal
Bleed Air Shutoff/Regulating Valve
Intercooler
Bleed Air Overtemperature
Switch PneumaticSuction Gauge Gyro Inlet Air Filter VacuumRegulatorValve PneumaticSystem Check Valves Check Valve PressureRegulator/Relief
Valve
Pilots Turn and Bank Indicator Engine Bleed Ports DirectionalGyro Gyro Horizon
17
14
10.Ejector
11.Door Seal Solenoid Valve
12.Turn and Bank Trim Valve
13.GroundBleedAir Bypass Valve
14.Deice Boots
15.WingDeiceValve
16.Tail Deice Valve
17.PressureSwitch (N.O.) 15 ± 1 psi
Pneumatic System Schematic Figure 1
EFFECTIVITY:
040-999
Jan 109036-10-00
PIPERAIRCRAFT
PA-42-720(AdvancedTrainer)
MAINTENANCEMANUAL
A. Distribution(continued)
(j)
VacuumRegulator:(Figure1) Thevacuumregulatorislocatedinthecockpit,behindtheleftsideoftheinstrumentpanelat fuselagestation66.50.Thevacuumregulatorregulatesvacuumforspinningthegyrosat4.5 to5.2inchesofmercury,referencetocabinpressure.
(k)
GyroInletFilter:(Figure1) Thegyroinletfilterislocatedinthecockpit,behindtheleftsideoftheinstrumentpanelat fuselagestation66.50.Theinletfilterfilterscabinairinlettogyrosto 0.3micronparticlesat 99%efficiency.
(I)
PneumaticPressureGauge:(Figure1) Thepneumaticpressuregaugeislocatedinthecockpit,ontheupperleftsideof theinstrument panel.Thepneumaticpressuregaugedisplayspneumaticsystempressuretothepilot.
(m)SuctionGauge:(Figure1) Thesuctiongaugeislocatedinthecockpit,ontheupperleftsideof theinstrumentpanel.The suctiongaugedisplaysgyrovacuumtothepilot.
(n) DoorSealSystem:(Referto 52-00-00fordetailedinformation.)Bleedair,fedtothepneumaticsystempressure isregulated to the
regulator/relief, androuted doorsealthroughathreewayvalve.Thisvalvedirectsregulatedairto thedoorsealat pressurizationanddumpspressureoverboardwhenitisnotdesired.
2. BleedAir ShutoffValveRemoval
(a)
Removetopcowlofaffectedengineto gainaccesstoshutoffvalveontheleftsideofengine.
(b)
Removesafetywireandboltsto removecouplingssecuringvalveassemblyin bleedline.
(c)
Disconnectelectricalconnectorfromvalve.
(d)
Removevalvefromnacelle.
3. BleedAirShutoffValveInstallation
NOTE: If leakageoccursat couplings,linetheflangeswithteflontapethreadsealant,(Referto Listof ConsumableMaterialsin 91-00-00.)makingsuretapeis placed1/16inchfromthe edgeof the flangeto preventingestionof tape in system.
(a)
Installnewvalveinpositionandsecurecouplings.Torquecouplingboltsto35-45inch-poundsandsafetywire.
(b)
Installelectricalconnectortovalve.
4. IntercoolerRemoval
(a)
Removeturtlebackcowlto gainaccessto intercooler,beingsureto removescrewssecuring theinlet andoutletducts. (Referto 54-00-00.)
(b)
Disconnectand removeallducts andplumbing.
(c)
Removescrewsaroundflangeof the intercooler.Withdrawassemblyfromfirewall.
5. IntercoolerInstallation
(a)
Mountintercoolerandcoolingair inletductto firewallwith screwspreviouslyremoved.
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