AirComm Corporation Cessna 340 340A Installation Service Manual

							KEITH PRODUCTS, INC. INSTALLATION INSTRUCTION AND SERVICE MANUAL 
 CESSNA MODEL 340/340A    
SECTION III   SERVICE AND MAINTENANCE PROCEDURES 
 
 PRESSURIZED AIRCRAFT CONDENSATE DRAIN VALVE OPERATION 
 
One result of an aircraft air conditioning system operating is the removal of moisture 
from the warm air in the cabin as the system circulates the air over the evaporator coil.  
Because of this, the evaporator has a drain pan and drain tube to allow  the  
accumulated moisture to run overboard.  Non-pressurized aircraft normally have an 
open drain system functioning all the time. 
 
All pressurized aircraft equipped with Keith Products air conditioning systems are 
equipped with a condensate drain valve in the line with an instrument panel mounted 
switch. 
 
The purpose of the valve is to allow the pilot to control the outflow of water from the 
evaporator pan.  Any momentary application of the drain switch allows a small amount 
of pressurization air to escape through the drain tube and valve.  However, past 
experience has shown that the aircraft pressurization systems have more than 
adequate capacity to handle even inadvertently leaving the switch on for extended 
periods of time. 
 
Aircraft operated in high humidity areas can generate a large amount of water in the 
evaporator in a short period of time from takeoff to cruise altitude. 
 
The condensate drain switch should be put in the ON position for two (2) to three (3) 
minutes after reaching cruise altitude to drain off the excess water.  The switch should 
then be returned to the OFF position. 
 
Since the capacity of the drain pan is not necessarily large, continued operation in a 
high humidity environment could result in a spillage of water out of the evaporator box 
into the interior of the aircraft, if the system is not drained. 
 
Good practice would be to drain the line for a moment or two before shutting the aircraft 
down at the destination airport, thus assuring drain pan capacity at the next takeoff. 
 
 
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							KEITH PRODUCTS, INC. INSTALLATION INSTRUCTION AND SERVICE MANUAL 
 CESSNA MODEL 340/340A    
SECTION IV  AIRCRAFT DOCUMENTS 
 
 SAMPLE 
 
WEIGHT AND BALANCE SUPPLEMENT 
 
MODEL:  CESSNA 340 
 
SERIAL NUMBER:                      
 
REGISTRATION NUMBER:                           
 
 
ITEM     WEIGHT  ARM  MOMENT 
 
1.  PREVIOUS EMPTY WEIGHT 
 
2.  ADD AIR CONDITIONER 
 
     a)  COMPRESSOR/CONDENSER  52.4   79.0  4139.6 
 
     b)  EVAPORATOR    15.0             242.0  3630.0 
 
     c)  HOSES/FITTINGS/ELECTRICAL  12.0             150.0  1800.0 
 
     d)  DUCTING      6.0             183.0  1098.0 
 
 
NEW EMPTY WEIGHT:                             
 
NEW AIRCRAFT EMPTY WEIGHT C.G.:                                     
 
NEW USEFUL LOAD:                                          
 
 
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