Unit installation
Table Of Contents
- Introduction
- Installation
- Physical Data
- Electrical Data
- Dimensional Data
- Startup
- Operation
- Global UNT Controller Installation and Operation
- General Description
- Optional Sensors
- Sensors and Transducers
- Control Wiring
- External Voltage Inputs
- Interlock Wiring
- Unit Set Points and Calibration
- Optional Sensors
- Field Wiring
- Power Wiring
- Power Supplies
- Analog input signals
- Digital input signals
- Remote Stop/Start
- Chilled Water Flow Switch
- Digital Outputs
- External Alarm Annunciator Circuitry
- PC Connection
- Software Identification
- Controller Inputs /Outputs
- Additional Global UNT Features
- Alarms
- Zone Terminal (Optional)
- Zone Terminal Glossary
- UNT Troubleshooting Chart
- MicroTech Controller Installation and Operation
- Sensors and transducers
- Control wiring
- Remote 4-20 milliamp signals
- Interlock wiring
- Unit set points and calibration
- Modem kit
- Lead-Lag
- Field Wiring
- Power Wiring
- Power Supplies
- Analog Input Signals
- Digital Input Signals
- Remote Stop/Start
- Chilled Water Flow Switch
- Digital Outputs
- Chilled Water Pump Relay
- External Alarm Annunciator Circuitry
- PC Connection
- Telephone line
- Software Identification
- Controller Inputs /Outputs
- Reset Options
- Soft Loading
- Manual Operation
- Compressor Staging
- Head Pressure Control
- Pumpdown Control
- Safety Systems
- Circuit Alarm Conditions
- System Alarm Conditions
- Sequence of Operation
- Start-Up and Shutdown
- Keypad / Display
- Menu Descriptions
- Trouble Analysis for the MicroTech
- Test Procedures
- Unit Maintenance
- Service
IOMM AGZ-3 AGZ 035A through 065A 35
NOTE: Before adjusting superheat, check that unit charge is correct and liquid line
sightglass is full with no bubbles.
The suction superheat for the suction leaving the evaporator is set at the factory for 8° to 12°F at full
load. To have full rated unit performance the superheat must be about 8 degrees F at 95°F outdoor
ambient.
Crankcase Heaters
The scroll compressors are equipped with externally mounted band heaters located at the oil sump
level. The function of the heater is to keep the temperature in the crankcase high enough to prevent
refrigerant from migrating to the crankcase and condensing in the oil during off-cycle.
Power must be supplied to the heaters 24 hours before starting the compressors.
Water Cooler
The water cooler is of the direct expansion type with removable internally finned tubes. The copper
tubes are individually rolled into heavy duty steel tube sheets and sealed by a steel refrigerant head.
The water connection nozzles which enter and leave the shell are on the same side of the unit. No
special attention is required for the cooler except that clean, filtered water should be supplied.