Vogt P-24AL, Руководство по обслуживанию

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P24AL & P34AL Service Manual
INSTALLING YOUR TUBE-ICE MACHINE
12/2016
3-12
Water Tank Drain. This valve and connection is for the purpose of flushing and draining the water
tank of impurities, foreign material and cleaning chemicals used during servicing. It should be piped
to an open drain or sump for visible discharge. It can be tied in with the overflow line but no others.
Water Tank Overflow. A 3” FPT connection on the side of the water tank is provided to carry
away overflow water during the thawing (harvest cycle). This water contains ice fines accumulated
during harvesting and dissolved solids accumulated during the freezing cycle.
Do not reduce the
size of this line . Three inches is needed to provide sufficient area for ice fines to be flushed out,
especially if the incoming flushing water is 55

F (13

C) or below. This overflow line should not tie
in with any other drain line except the water tank drain.
Unless water quality is superior, do not discharge the overflow water to the cooling tower system.
This water contains additional dissolved solids left from the ice making process and can lead to
excessive condenser fouling or cooling tower chemical usage. It is recommended that a heat
exchanger be used in place of direct contact with condenser water.
Receiver. The receiver used to supply hot thaw gas must be sized adequately to provide a sufficient
amount of thawing gas to the freezer. Table 3-2 shows the volume required to hold the refrigeration
charge of the freezer and the hot gas required for the thaw cycle. It is recommended that a heating
coil be installed in the receiver to assure that the liquid ammonia is at saturated temperature at the
start of each thaw period.
Note: Additional storage volume may be required for the interconnecting piping. Add volume of
interconnecting piping to the values shown in Table 3-2
RECEIVER VOLUME (Cubic Feet)
MODEL With Heating Coil With out Heating Coil
P24AL 30 45
P34AL
50 70
Table 3-2
Receiver Volume Requirements
Thaw Gas Pressure Regulator. The thaw gas pressure regulator is a 2” solenoid operated pressure
combination regulator and shut-off valve (see Figures 1-2 and 1-5 for locations). Do not reduce the
size of this line . This valve is designed to carry the proper amount of thaw gas to the evaporator
during the harvest cycle. See Page 5-7 for operating instructions.
Suction Pressure Regulator. When a P24AL or P34AL is attached to a central system, a pressure
regulator will be required (see Figures 3-15 through 3-16 for location). This regulator (usually
furnished by the purchaser) must be a combination back pressure regulating and stop-type valve.
The usual minimum pressure drop across this type valve is 2 psig; therefore, the valve must be set to
maintain a freezer pressure that is at least 2 psi above the maximum general suction pressure.
Compressor Unloading. When a P24AL or P34AL is attached to a dedicated compressor system,
unloading of the compressor will be required. A minimum compressor unloading during the harvest