KA Tech Note #02-2 - Liquid Cooling for XX 75E Projectors - 12/03/02

Overview

In Kinoton 70 mm and Large Format / Special Venue projectors (XX 75E series) the film gate, the intermittent sprocket motor and the intermittent motor amplifier are liquid cooled. The heated liquid is pumped through 8 mm PVC hoses to the heat exchanger cabinet. Inside, the heat is removed by a refrigerated copper heat exchanger submerged in the coolant reservoir. The refrigeration system dissipates its heat via an air cooled condenser. The circulation of coolant results from the use of a high performance pump.

A paddle-wheel flow sensor in the projector monitors the coolant flow. If the flow is too weak the sensor communicates to its circuit board, which activates a relay. This contact is connected to the projector’s circuitry such that an “external film break” signal is detected and stops the projector.

To avoid damage to the intermittent sprocket motor and amplifier, and other projector components, the flow control unit must not be bypassed! If an external film break signal from the flow control unit is detected, the reason why the flow is too weak, and the propeller is turning too slowly, must be found and corrected.

Possible reasons are:

• contaminated coolant has thickened, and reduced the size of hoses and chambers
• pipe sealant or other particles are obstructing the hoses or coolant chambers
• too little cooling fluid in system
• the inlet hose is longer than 5 meters (15 feet)
• the inlet hose is buckled
• the cooler is not installed on the same level with the projector.
• the flow sensor is defective or jammed

Checking the flow speed

The coolant flow through the motor, amplifier and film gate must be at least 1 litre/minute.

Remove the black plastic flow sensor housing - the propeller is visible. If the propeller is turning at about 1000 pulses/minute no details of the propeller are visible - it is a blur. If you can see the propeller blades the propeller is turning too slowly.

In this case the projector must not be operated.

The intermittent sprocket motor, the amplifier heat sink and the film gate calcify very fast if the specified coolant composition (see coolant specifications) is not strictly met. The damage which can arise can be very expensive.

In case of damage due to improper coolant, Kinoton GmbH or Kinoton America does not accept any liability or provide any warranty.

Installation

• The cooling unit should be positioned on approximately the same level as the projector.
• The cooling unit should be positioned not more than 5 meters (15 feet) away from the projector.
• The coolant hoses should be run as straight as possible, with minimal variations in its height and without narrowing the cross section, for instance by sharp bends.
• The heat exchanger must get enough air, so it must be positioned at least 30 cm (1 foot) away from walls.
• Put outlet and inlet hoses onto the associated hose barbs (note coolant flow direction arrows).
• Bind the hoses with clamps.
• Fill the heat exchanger’s reservoir with coolant (see specifications). The coolant level must be between the blue (minimum) and the red (maximum) markings.
• Connect the heat exchanger to 230 V power and turn on the main switch.

Maintenance

• Each day the cooling fluid level must be checked and filled if necessary.
• Each day the electronic thermostat’s display must be verified to read 18°C ± 2°C
• The operator should only clean the outside of the cooling device.
• Non-distilled water or cleaning chemicals must not contaminate the coolant inside.
• The fins of the air condenser should be cleaned with a fine brush each 4 to 6 weeks. Do not bend the fins and do not touch them with your hands or sharp tools.
• Annual cleaning and maintenance of the internal components should be performed only by authorized Kinoton service technicians.

Coolant specifications

• 5 parts distilled water + 1 part “Tyfocor” additive
• Do not use more Tyfocor, because the cooling fluid will get too thick and the coolant flow will be reduced.
• specifications for the distilled water (to be purchased locally):
  • demineralised
  • chemically pure
  • pH between 5 and 7
• DO NOT use tap water or “spring water”. Use only distilled water as specified.
• ONLY TYFOCOR can be used as the additive. Antifreeze, or any other substance, will not work properly and can cause serious damage.

  “Tyfocor” additive is available from Kinoton [part number 1000-390-27004; 10 L., makes 60 L. (16 gal.) of coolant].

Operating specifications

• Returning coolant temperature: 15°C to 40°C (59°F to 104°F)
• Output coolant temperature: 18°C ± 2°C (64°F ± 10°F) [as displayed on electronic thermostat]. The water temperature should not be less than 16° C (60°F), to prevent water condensing on hoses and fittings inside the warm projector cabinet
• Coolant flow: 1 L/min. (.26 gal./min.) minimum