Welbilt Koolaire KD0270A, Technician'S Handbook, Page: 85 / 136

Part Number STH047 Rev01 10/18 85
FINAL ANALYSIS
The column with the highest number of check marks
identifies the refrigeration problem.
Column 1 – Harvest Valve Leaking
A leaking harvest valve must be replaced.
Column 2 – Low Charge/TXV Starving
Normally, a starving expansion valve only affects the freeze
cycle pressures, not the harvest cycle pressures. A low
refrigerant charge normally affects both pressures. Verify
the ice machine is not low on charge before replacing an
expansion valve.
Add refrigerant charge in 2 oz. increments as a diagnostic
procedure to verify a low charge. (Do not add more than
the total charge of refrigerant). If the problem is corrected,
the ice machine is low on charge. Find the refrigerant leak.
The ice machine must operate with the nameplate charge.
If the leak cannot be found, proper refrigerant procedures
must still be followed. Change the liquid line drier,
evacuate the system and weigh in the proper charge.
If the problem is not corrected by adding charge, the
expansion valve is faulty.
Column 3 – TXV Flooding
A loose or improperly mounted expansion valve bulb
causes the expansion valve to flood. Check bulb mounting,
insulation, etc., before changing the valve.
Column 4 – Compressor
Replace the compressor and start components. To receive
warranty credit, the compressor ports must be properly
sealed by crimping and soldering them closed. Old start
components must be returned with the faulty compressor.