Operation Of Mix Pump; Mix Pump Cleaning; Disassembly And Inspection Of Removable Parts - Stoelting F431 Service Manual

3.13 OPERATION OF MIX PUMP

The mix pump switches are located in the upper left hand
corner, inside the refrigerated cabinet. When a pump
switch is placed in the ON position, the mix pump motor
will start pumping mix into the machine cylinder. When
the set pressure is reached, the mix pump will shut off
automatically. When the switch is placed in the OFF posi-
tion, the mix pump will be inoperative.
The mix pump motor is equipped with an internal
overload that will "trip", disabling the pump when
the motor is overloaded. Consult the trouble shoot-
ing section for corrective information. The internal
overload will automatically reset after cooling. If
the condition continues, contact a qualifi ed service
person.
A. Mix Operation: The peristaltic mix pump contains
one continuous mix pump hose. When looking at
the face of the peristaltic mix pump, the left side
of the hose is the suction or pickup. The right
side of the hose is the discharge. Mix is drawn
up the suction side of the hose and transferred
through the discharge side to the machine (see
Figure 3-15).
Air Line
Mix
Intake
Figure 3-15 Mix Pump Hose Routing
B. Air Operation: The air compressor operates
whenever the peristaltic mix pump is running.
Air enters through a check valve on the piston
downstroke. The air is discharged through a
second check valve, on the piston upstroke. The
air and mix join at the tee and then travel to the
machine.
C. The overrun adjustment is preset at the factory.
If an adjustment becomes necessary, refer to
Section 4.
NOTE
Air/mix to
Freezing
Cylinder
3-way
Tee
Any cleaning procedure must always be followed
by sanitizing before fi lling machine with mix. (Refer
to section 3.3)

3.14 MIX PUMP CLEANING

The mix pump is approved for CIP (clean in place) and
is thoroughly cleaned as cleaning solutions are pumped
through the machine. We recommend completely disas-
sembling the pump and disconnecting tubing every 14
days for inspection of parts to confi rm the CIP has been
properly performed. If any residue is detected clean or
replace those parts as outlined below.
A. Place the Main Power OFF/ON and Freezing
Cylinder OFF/ON switches ON position and press
the CLEAN button. Allow the auger to agitate for
5 to 10 minutes.
B. Remove suction tube from mix container. Draw
off the mix remaining in machine barrel.
C. Pump 2 gallons (7.5 liters) of potable water through
machine until water at spigot is free of mix.
D. Pump 2 gallons (7.5 liters) of 90° to 110°F (32°C to
43°C) detergent solution water through machine.
The use of soft water is recommended, along with
dishwashing detergents such as "Joy," "Dawn,"
or equivalent.
E. Place mix pump switch in OFF position. Open
spigot to relieve remaining pressure.
F. Press the CLEAN button to stop the auger and
place the Main Power OFF/ON and Freezing
Cylinder OFF/ON switches in the OFF position.
3.15 DISASSEMBLY AND INSPECTION OF
REMOVABLE PARTS
Inspection of removable parts should be made whenever
maintenance is performed or pump requires disassembly.
Hazardous Moving Parts
Revolving pump head can grab, mangle, and cause
serious crushing injury. The Main Power OFF/ON
switch must be placed in the OFF position for cleaning
and power must be disconnected when disassembling
or servicing.
If the mix lines or air line is diffi cult to remove,
soften tubing with a rag soaked in hot water. Hose
connections may be sprayed with Haynes Sanitary
Lubricant for ease of removal. Do not loosen or re-
move the mix pump cover wing nuts. Maintain the
mix pump hose in its operational condition.
23
NOTICE
WARNING
NOTE