6
Introduction
Models 358 & 359
Running Specifications
Expansion Valve Setting
404A/HP62: 20 - 22 PSI (138 - 152 kPa)
Low Side Pressure
Low side pressure = expansion valve setting
To adjust the low side pressure, place the gauge on
the low side suction port at the compressor. With the
compressor running, turn the adjustment knob of the
automatic expansion valve clockwise to raise the low
side pressure and counterclockwise to lower the
pressure.
High Side Pressure
Air Cooled:
The following chart indicates normal
operating head pressures at various ambient
temperatures:
Ambient Temperature
Normal Operating Head
Pressures
F
C
PSI
70
_
21.1
_
240 -- 270
(1,655 -- 1,862 kPa)
80
_
26.7
_
270 -- 300
(1,862 -- 2,069 kPa)
90
_
32.2
_
300 -- 340
(2,069 -- 2,344 kPa)
100
_
37.8
_
340 -- 380
(2,344 -- 2,620 kPa)
Water Cooled:
The high side pressure for water
cooled units is determined by the water valve. The
water valve is factory set to maintain a high pressure
of 235 PSI (1,620 kPa). To adjust the high pressure,
place the gauge on the high side access port. Turn
the adjustment knob on the water valve clockwise to
lower the high side pressure and counterclockwise
to raise the pressure.
The high side pressure switch is factory set at 440
PSI (3,034kPa) for 404A/HP62. In the event of a
water loss, this switch will sense a rise in pressure
and deactivate the unit.
EPR Valve Setting
The product temperature in the mix hopper is
maintained by the main refrigeration system and can
be adjusted by the EPR (evaporator pressure
regulator) valve. The EPR valve is factory set at 67 -
69 PSI (462 - 476 kPa) in order to maintain hopper
product temperature below 40
_
F (4
_
C). To adjust
the hopper temperature, place the gauge on the
access port at the inlet of the EPR valve. With the
compressor running, loosen the locking nut and turn
the adjustment screw (located on the top of the
valve) clockwise to raise hopper temperature and
counterclockwise to lower the temperature. When
the adjustment is complete, tighten the locking nut.
