Both the EPR and the 2-way solenoid valves
are normally closed, so the EPR must be
powered only during refrigeration and the
2-way valve only during defrost.
The 3-way valve is normally in refrigeration
mode. Energizing the solenoid opens the pilot
valve port which directs high pressure
Koolgas vapor to the piston chamber. Pushed
to its opposite position, the piston assembly
stops the suction line and opens the Koolgas
line. A bleed port in the piston provides for
de-compression of the piston chamber when
the pilot port closes.
Troubleshooting Koolgas Valves
HUSSMANN CORPORATION • BRIDGETON, MO 63044-2483 • Printed in USA
Revised August 1, 1996 P/N 340272A
7 - 3
Malfunction Cause Action
Fails to Open Dirt plugging pilot port Disassemble and clean
Solenoid not energized
-bad solenoid Replace solenoid
-circuit open Find and repair open
-NOT in defrost mode Correct defrost clock problem
Fails to close Piston port plugged Clean or replace
Barrel or piston scored Replace
Dirt in piston chamber, causing drag Clean or replace
Stuck in defrost mode Correct defrost clock problem
To Next Page
Loading...
