VOGT ICE TUBE-ICE P-24A, Service Manual

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P24A & P34A Service Manual
SERVICING OPERATIONS
12/18/12
9-2
Hand Expansion Valve.
The hand expansion valve is located directly after the “A1” solenoid
valve. This valve should be set at a point where the float switch is open for a length of time
approximately equal to the time it is closed.
Freezer Pressure Switch.
The freezing time period for producing ice of a desired thickness is
controlled by the freezer pressure switch (2PS), Figure 9-1, located inside the control panel.
The original switch was set at the factory to produce ice of recommended thickness. Look at the
“Certificate of Test” which was provided with the machine for a sample set of pressure readings with
corresponding time periods and water temperatures. Also see TABLE 11-8/ 11-9, Operating Vitals
for typical settings. When making adjustments, allow two ice discharging cycles between
adjustments. Switch adjustment is as follows: See Figure 9-1.
1. Turn the low signal adjustment nut CCW until low signal setting indicator is fully down. Turn
the high signal adjustment nut until high signal setting indicator is slightly beyond the actuation
setting of 55 psig.
2. Starting with the pressure above the actuation pressure, reduce the pressure to desired actuation
pressure of 55 psig, contact opens.
3. Advance the low signal adjusting nut until the switch actuates and contact closes.
FIGURE 9-1
ASCO Freezer Pressure Switch (2PS)
It is preferable that the freezing cycle be such that a small diameter hole remain in the center of the
ice cylinder (1/16” diameter for 7/8” diameter ice, 1/8” diameter for 1 1/8” diameter ice, 1/4”
diameter for 1 3/8” diameter ice). This insures that the freezing cycle is not extended unnecessarily
and eliminates a possible opaque core in the center of the ice, as well as a loss of production.
High-Low Pressure Switch.
The high-low pressure switch (1PS), Figure 9-2, is a two pole dual
function switch mounted to the frame near the compressor. It protects the machine from possible
damage due to abnormal pressure during operation.