Vogt P-24AL, Service Manual

Page: 57 / 149

P24AL & P34AL Service Manual
START-UP & OPERATION
12/2016
5-3
Charging from Tank Truck (dedicated high side only). The system may be charged by bulk from
a tank truck and be pumped directly into the receiver through the drain valve.
Follow these instructions with caution:
1.
Using an ammonia approved charging hose, connect one end to the drain/charging valve in the
bottom of the high pressure receiver.
2. Connect the other end of the charging hose to the tank truck. It is best to have a gage in this line
to indicate pressure.
3. Open the drain/charging valve and the fill valve from the tank truck.
4. While observing the sight glass on the high-pressure receiver, fill the receiver to the proper
volume.
5. Make sure the charging valve is closed and the cylinder valve is closed before attempting to
disconnect the hose. Use caution when disconnecting the charging hose, it will contain liquid
ammonia and should be disposed of in accordance with local, state and federal safety and
environmental rules.
! CAUTION !
Do NOT attempt to bulk charge the machine through the freezer
charging valve (28). The freezer will not hold the full charge
without exposing the compressor to serious damage.
! CAUTION !
Charging from Cylinders (dedicated high side only). The machine may also be charged from
refrigerant cylinders. To charge from cylinders, the compressor will have to operate to transfer the
ammonia from the freezer to the receiver. Again, make sure all the necessary valves are opened for
operation and the compressor crankcase heater has been energized for a minimum for four hours.
Follow these instructions with caution:
1.
Using an approved for ammonia charging hose, connect one end to the charging valve (28) in the
liquid line near the freezer.
2. Lay a full cylinder of anhydrous ammonia horizontally with the cylinder valve outlet pointing up
to withdraw liquid and the bottom end raised about 2” higher than the top end.
3. Connect the other end of the charging hose to the cylinder valve. It is recommended that a gage
be attached to this line to indicate cylinder pressure.
4. Close the liquid line stop valve (29) or at the receiver.
5. Open charging valve (28) and carefully purge air from the charging hose.
6. Open the cylinder valve slowly, checking for leaks in the line and allow the suction pressure to
build up to approximately 40 psig and check again for leaks in the system.
7. Set the freeze timer (1TR) to maximum setting. If the machine contains a pressure switch (2PS)
in place of the freeze timer, disconnect and locked out the power, open the control panel door and
disconnect wire #24 from the freezer pressure switch (2PS), then turn the power back on.
8. Check compressor rotation by starting and stopping the compressor momentarily. If the
compressor starter is wire to (3CR) then jog the compressor by using the green START push
button (2PB) and the red STOP push button (1PB). Correct compressor rotation is indicated by
an arrow on the outer rim of the oil pump assembly (opposite the shaft end of the compressor.