Vogt P-24AL Service Manual Download

Page: 36 / 149

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

P34AL

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