CyberChiller Series Installation, Operation & Maintenance Manual

cycle, one scroll remains stationary while the other scroll orbits around the first. As this motion occurs, gas is drawn into the scrolls and moved in increasingly smaller pockets toward the center. At this point, the gas, now compressed to a high pressure, is discharged from a port in the center if the fixed scroll. During each orbit, several pockets of gas are compressed simultaneously, creating smooth, nearly continuous compression.

Due to the design of the scroll compressor, the internal compression components always start unloaded even if the system pressures are not balanced. In addition, since internal compressor pressures are always balanced at start-up, low voltage starting characteristics are excellent for scroll compressors

With fewer moving parts, the scroll compressor sets the industry standard for reliability among one and a half to twelve horsepower compres- sors. The compressor’s simple design and proven day-to-day performance means less maintenance calls for field personnel.

The scroll compressor has demonstrated superior durability. Its axial and radial compliance make the scroll

compressor more tolerant to liquid refrigerant and debris - two of the most common causes of system failure.

The scroll compressor is quiet, but not silent. On average, the compressor is up to five decibels quieter than standard piston compressors. A scroll compres- sor, however, has different sound characteristics from reciprocating compressors. These sounds do not affect system reliability or performance.

Upon shut-down of a normal run cycle, the compressor will run backwards for one or two seconds as the scrolls internal pressures are equalized. A short reverse rotation “burp” will result. This sound is normal. A check valve in the discharge tube of the compressor prevents the compressor from running backwards for more than a second or two. This normal direction reversal of the scrolls at shut down has no effect on compressor reliability.

Each scroll compressor comes equipped with a crankcase heater, used to evaporate any liquid that may have migrated to the compressor during extended periods on non-operation (>12 hours). The crankcase heaters are equipped with over current protection.

CAUTION

Prior to initial start-up (only when main power has been disconnected for 12 hours or longer), allow at least ten (10) minutes (two (2) hours is recommended) with main power reconnected. This will allow sufficient time for the crankcase heaters to evaporate any liquid that may have migrated to the compressor crankcase. When this procedure is completed, the CyberChiller is ready to be run.

Automatic, staged starting of the compressors is provided to prevent an in rush of current to the CyberChiller. High and low pressure safety switches prevent operation of the compressor during high or low pressure conditions.

1.2.3.8Strainer

A “Y” strainer is included to remove any debris that may be circulated to the chiller.

1.2.4Safety Features

Low and high-pressure switches are provided for each refrigeration circuit. The pressure switches are non- adjustable encapsulated control switches. If a high pressure switch is tripped for any reason, it must be manually reset. The cause for tripping of the high pressure switch must be determined. The low pressure switches are reset automatically. These pressure switches are installed as safety devices and will help prevent compressor failure or other serious damage to the system.

A flow switch is provided which will disable the refrigeration circuits if the coolant flow drops below a preset limit.

A blocked flow bypass valve is recommended for field installation to ensure proper return flow to the chiller at all times.

Manual reset circuit breakers will open to de-energize a failed component if electrical overload conditions are encountered.

(©October, 2006)

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