Manuals / Foster / Kitchen Appliance / Ice Maker

Foster F20, F85, F40, F60, FCI30, FCI85 Principle of Operation, How it works, Freezing Cycle, Board

Models: FCI60 FCI30 FCI20 FCI40 FCI85 F60 F40 F20 F85

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COMPRESSOR, WATER INLET SOLENOID VALVE, HOT GAS VALVE

NOTE: The length of the defrost cycle is (non-adjustable) automatically determined by the microprocessor of The P.C. BOARD in relation to the time T2 necessary for the unit to reduce the evaporator temperature from 0˚C (35˚F) to -1 3˚C (8.5˚F) and of the ambient temperature, as illustrated in Table C.

As shown it is possible to have a different length of the defrost cycle in connection with the different length of the second phase of the freezing cycle T2 relative to the ambient temperature situations; shorter when the ambient temperature is high and longer in colder ambients so to partially compensate the length of the freezing cycle, which is longer in high ambient temperatures and shorter in low ones.

H.Check, during the defrost cycle, that the incoming water flows correctly into the sump reservoir in order to refill it and that its surplus overflows through the overflow drain tube.

I.Check the texture of ice cubes just released. They have to be the right shape with a small depression of about 5-6mm in their crown. If not, wait for the completion of the second cycle before performing any adjustment.

If the ice cubes require a correction to their shape, it is possible to modity the length of the timed freezing cycle by changing the DIP SWITCH keys setting as illustrated in table B.

It the ice cubes are shallow and cloudy, it is possible that the ice maker runs short of water during the freezing cycle second phase or, the quality of the supplied water requires the use of an appropriate water filter or conditioner or the installation of the optional water drain valve kit KWD.

J.To be sure of the correct operation of the ice level temperature sensor, located in one side of storage bin liner, during the defrost cycle place one shovel of ice cubes in contact with its probe for approx. 30 sec.-1 minute.

As the temperature of storage bin sensor reaches the value of +2˚C (35˚F), the ice level control transmits a signal to the microprocessor of the P.C. BOARD in order to stop the ice maker operation at the end of the defrost cycle with the simultaneous glowing of the 3rd RED LIGHT, to monitor the BIN FULL situation (Fig.6). Page 13

With no more ice cubes in touch with the ice level control the temperature of its probe progressively rises to reach + 4.5˚C (40˚F) and at this point the ice machine restarts to initiate a new freezing cycle with the simultaneous extinguishing of the 3rd RED LIGHT.

NOTE The CUT-INRANGE OF THE ICE LEVEL CONTROL SENSOR can be adjusted as shown in table D; its cut out setting remains however at + 2˚C (35˚F).

6.Principle of Operation

6.1How it works

In the cube ice makers the water used to make the ice is kept constantly in circulation by an electric water pump which primes it to the spray system nozzles from where it is diverted into the inverted mould cups of the evaporator. A small quantity of the sprayed water freezes into ice; the rest of it cascades by gravity into the sump assembly below for recirculation.

6.2Freezing Cycle

The hot gas refrigerant discharged out from the compressor reaches the condenser where, being cooled down, condenses into liquid. Flowing into the liquid line it passes through the drier filter, then it goes all the way through the capillary tube where, due to the heat exchanging action, it loses some of its heat content so that its pressure and temperature are lowered as well.

Next the refrigerant enters into the evaporator serpentine (which has a larger l.D. than the capillary) and starts to boil off; this reaction is emphasised by the heat transferred by the sprayed water.

The refrigerant then increases in volume and changes entirely into vapour.

The vapour refrigerant then passes through the suction accumulator (used to prevent any small amount of liquid refrigerant reaching the compressor) and through the suction line. In both the accumulator and the suction line it exchanges heat with the refrigerant flowing into the capillary tube (warmer), before being sucked into the compressor and recirculated as hot compressed refrigerant gas.

The freezing cycle is controlled by the evaporator temperature sensor (which has its probe in contact with the evaporator serpentine) which determines the length of the first and second portion of it and it is signalled by the glowing of the 6th RED LED.

The first portion length or time T1 (non-adjustable) is equal to the time required by the temperature sensor to fall to 0˚C (35˚F). When reached, it is signalled by the glowing of the 5th RED LED.

NOTE If, after 15 minutes, the evaporator temperature has not yet reached the value of 0˚C (35˚F) (due to a partially or total shortage of refrigerant or to a too high condensing temperature, etc.) the sensor, through the P.C. BOARD, causes the unit to stop the operation with the simultaneous glowing of the SECOND RED WARNING LED (Fig. 7). Page 13. After having eliminated the source of the unit trip off, to restart the machine operation it is necessary first to rotate the program selector to the RE-SETposition, then put it again on to OPERATION position or, alternatively, switch OFF and ON the unit at the power line Main Switch.

The second portion length of freezing cycle or time T2 (non-adjustable) is equal to the time required by the evaporator temperature to go from 0˚C (35˚F) to -13˚C (8.5˚F) on models 20, 30, 40 and 60 or to -16˚C (3˚F) on model 85. The sensor will light-up the 4th RED LED.

NOTE In case the time T2 gets longer than 45 minutes, the unit stops with the glowing of the second RED WARNING LED.

Also in this case, after having eliminated the source of the trip OFF to restart the machine it is necessary first to rotate the program selector to the RESET position then put it again on OPERATION or, switch OFF and ON the unit at power line Main Switch.

The third portion or time Ta (added time) of the freezing cycle is controlled by the electronic timer of P.C. BOARD. As the evaporator temperature reaches the value of -13˚C (8.5˚F) or to -16˚C (3˚F); the sensing probe of the evaporator sensor (in contact with the serpentine) changes its electrical resistance causing a low voltage current to flow to the P.C. BOARD which, thereby, activates an electronic timer.

NOTE The activation of the timer (Time mode) of P.C. BOARD is signalled by the glowing of fourth RED LED located in the front of the P.C.

BOARD.

ATTENTION In case the length of the second portion of freezing cycle or time T2, lasts as long as between 35 and 45 minutes, the third portion or time Ta gets skipped by the P.C BOARD which puts the unit directly in the defrost or harvest cycle.

The length of the third portion of the freezing cycle (adjustable) is pre-fixed and related to the setting of the DIP SWITCH keys 3, 4, 5, 6 and

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Foster F20 Principle of Operation, How it works, Freezing Cycle, COMPRESSOR, Water Inlet Solenoid VALVE, HOT GAS Valve
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FCI60, FCI30, FCI20, FCI40, FCI85 specifications

Foster F85, F20, F40, and F60 represent a remarkable lineup of industrial and commercial engines, celebrated for their reliability, efficiency, and advanced technology. These models cater to various applications, striking a balance between performance and economy.

The Foster F85 is designed for smaller machinery and equipment, perfect for light-duty tasks. It features a compact design that allows for easy installation in tight spaces. With a robust power output and energy-efficient operation, the F85 engine is coupled with advanced fuel injection technology that enhances performance and reduces emissions. Its low-maintenance requirements make it a favorite among operators looking for dependable machinery without extensive upkeep.

The Foster F20 escalates the performance, making it suitable for medium-duty applications. It boasts a higher torque output, allowing it to handle more demanding tasks while maintaining excellent fuel efficiency. The F20 integrates cutting-edge electronic control systems that optimize engine performance in real time. This model also features noise reduction technology, contributing to quieter operation in urban or sensitive environments.

Progressing to the Foster F40, this engine shines in heavy-duty applications, offering significant power and efficiency. With a robust design, the F40 is capable of withstanding harsh working conditions without compromising on performance. It features advanced thermal management systems that ensure optimal operating temperatures, enhancing engine lifespan and reliability. Moreover, the F40 incorporates modular components, promoting ease of repair and maintenance.

Lastly, the Foster F60 is the flagship model in this lineup and stands out for its exceptional power-to-weight ratio. It is engineered with the latest innovations in turbocharging, which provides increased horsepower while maintaining low fuel consumption. The F60 also integrates sophisticated diagnostic tools that help operators monitor performance and anticipate maintenance needs, thus minimizing downtime.

Across this range, Foster engines emphasize sustainability through reduced emissions and noise output, adhering to strict industry regulations. From the entry-level F85 to the high-performance F60, each model showcases Foster's commitment to engineering excellence and the evolving needs of industries. Whether for construction, agriculture, or commercial use, the Foster F series represents a wise investment for efficiency and reliability.