Heatcraft Refrigeration Products H-IM-79E Refrigerant Line Brazing Caution, Power Supply

Brazing

Refrigerant Line Brazing (Caution)

The electric expansion valve and the suction temperature sensor on the suction line are factory installed.

Care must be taken when brazing these lines at the evaporator.

Too high a temperature may destroy these components. Heat absorbing compounds or “wet rags” must be used to protect the electric expansion valve when brazing the refrigerant line connections. The suction line sensor should be removed before brazing.

Power Supply

The Beacon II board gets its 24 VAC power supply from a transformer mounted in the electrical end of each evaporator. On 208-240 volt systems the multi-tap transformer is shipped from our factory wired for 240 volts. If your supply voltage is 208 volt you must change to the 208 volt tap on the transformer.

VERY IMPORTANT: If the supply voltage to the evaporator is 208 volts, the primary tap of the transformer must be moved to the 208 volt tap.

This must be done for all the evaporators on that system.

If the 24 VAC power supply falls below 18 VAC the system may power down and shut off. When the power supply is corrected to 24 VAC the system will restart after the four minute hold-off period and resume normal operation.

On Beacon II systems the main power for the evaporator can be supplied separately from the power supply of the condensing unit. All wiring, however, must comply with local electrical codes.

Wiring

Wiring between the condensing unit and the unit cooler(s) will be as follows (see wiring diagrams):

•High voltage - There may be high voltage on the defrost heater relay and the fan relay. The evaporator may also be connected to a separate power supply from the condensing unit. See unit cooler spec. plate for ampacity.

•Low voltage - 24V Class II control circuit.

A total of five low voltage leads are required to connect the condensing unit to the evaporator. (See wiring diagram.) Two of these leads are for connecting the outdoor temperature sensor. The other three leads are for connecting the compressor relay,

service relay and 24V Common inputs.

All 24 volt wiring must be run separate from the line voltage wiring.

•Low voltage wiring must be 18 gauge minimum. For low voltage wiring, maximum distances are:

Condensing unit to Master evaporator	500 ft.
Between evaporators	500 ft.
Smart Controller to Master evaporator	1000 ft.

•Multiple units – The multi-in and multi-out are the communication connections. Connection sequence must follow the multi- out terminal to the multi-in terminal and the multi-out back to the multi-in terminal in a daisy chain loop.

•Alarm circuit - The onboard alarm is a dry set of NC contacts which closes to indicate an alarm. The type and wiring for the alarm is customer specified. Note that the alarm circuit does not distinguish or indicate what has caused the alarm.

•All wiring must comply with all applicable codes and ordinances.

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