Scotsman MAR1400 - Manual (Page 24)

Adjustments
The procedures provided in this section are
arranged in order to make specific adjustment and
removal and replacement information easy to
locate.
Read the instructions thoroughly before performing
any adjustment or removal or replacement
procedures.
1. ADJUSTMENT OF THE AUTOMATIC
EXPANSION VALVE
End to end frost on the evaporator drum is the
result of the correct expansion valve setting.
This valve may be manually regulated by means of
the adjusting stem.
Turning the adjustment to the left
(counter-clockwise) will increase the rate of
refrigerant flow.
Turning the adjustment to the right (clockwise) the
refrigerant flow to the evaporator is reduced.
Use the stem cap of the AXV for manual adjusting
operations.
Set the EPR first to -24°C (-11.2
o F) or 22 - 23
PSIG, then adjust the AXV to frost the refrigerant
drum completely.
If adjusting the EPR does not lower the suction
pressure to the desired level, and the suction
pressure at the condensing unit is lower than the
suction pressure at the EPR, the AXV is
overfeeding and should be adjusted to reduce
refrigerant flow.
When connected to a dedicated condensing unit,
frost back to the compressor may occur. If the
compressor is heavily frosted, adjust the AXV to
reduce refrigerant flow.
MAR1400 & MAR2000
December 2000
Page 24