Stoelting E131G Service Manual Download

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6.3.20 COMPRESSOR SUCTION PRESSURE TOO HIGH

CAUSE

CORRECTION

Expansion valve setting grossly out of
adjustment .................................................................... *Replace expansion valve.

NOTE

Expansion valve setting is preset for optimum balance of flow to barrel and hopper-

DO NOT ATTEMPT TO ADJUST THE VALVE SETTING.

Refrigerant overcharge ................................................. *Recover charge. Evacuate and recharge per nameplate by

...................................................................................... weight-ounces.

Internal mechanical trouble in compressor ................... *Replace compressor.

6.3.21 COMPRESSOR SUCTION PRESSURE TOO LOW

CAUSE

CORRECTION

Consistency setting is too firm. ..................................... Adjust fine consistency potentiometer firmer. If more adjustment is

...................................................................................... required, increase coarse amperage ‘AMP CRS’ setting 0.5 amps
...................................................................................... accordingly with fine potentiometer at mid-range (refer to control
...................................................................................... setup procedure in subsection 3.2). If unable to establish desired
...................................................................................... consistency, follow the coarse amperage consistency procedure
...................................................................................... in subsection 3.2.

Expansion valve setting grossly out of
adjustment ....................................................................

*Replace expansion valve.

NOTE

Expansion valve setting is preset for optimum balance of flow to barrel and hopper-

DO NOT ATTEMPT TO ADJUST THE VALVE SETTING.

Expansion valve orifice is plugged or valve is
defective. ....................................................................... Same as above.
Defective liquid line solenoid valve ............................... *Replace coil and/or liquid line solenoid valve.
Freezer refrigerant charge is low .................................. *Refer to Troubleshooting Subsection 6.3.22.

6.3.22 FREEZER REFRIGERANT CHARGE IS LOW

CAUTION

A FALSE DIAGNOSIS OF A SHORTAGE OF REFRIGERANT CHARGE IS POSSIBLE IN MODEL E131
AND F131 FREEZERS. IF ONLY ONE SIDE IS OPERATIONAL, THE INOPERATIVE SIDE MAY CONTAIN
A SIGNIFICANT PERCENTAGE OF THE TOTAL SYSTEM CHARGE. THIS CAN ALSO OCCUR IF BOTH
SIDES ARE OPERATIONAL BUT ONE SIDE IS IN IDLE MODE AND THE OTHER IN GREEN LIGHT
MODE. THE SYSTEM SIGHTGLASS DURING OPERATION OF THE GREEN LIGHT/OPERATIVE SIDE
MAY SHOW BUBBLES OR A PARTIALLY EMPTY CONDITION EVEN THOUGH THE TOTAL SYSTEM
IS PROPERLY CHARGED. THE GREEN LIGHT/OPERATIVE SIDE WILL OPERATE BOTH SIDES OF
THE FREEZER AND IN THE SAME MODE AS MUCH AS POSSIBLE. FURTHERMORE, TEST STEPS 1
AND 2 BELOW MUST BE CONDUCTED WITH SIMULTANEOUS OPERATION OF BOTH SIDES.

CAUSE

CORRECTION

Leak(s), prolonged use of gauges or frequent
usage of gauges. ..........................................................

DO NOT ADJUST THE EXPANSION VALVE!

...................................................................................... STEP 1: Observe sightglass for bubbles during refreeze. If
...................................................................................... sightglass is bubbling or partially empty, freezer refrigerant charge
...................................................................................... is low. (SEE CORRECTION BELOW). If sightglass is clear,
...................................................................................... proceed to Step 2.