This document describes the HE Series Central Chillers, which are designed for process cooling applications. The manual covers operation, installation, and maintenance for both air-cooled and water-cooled models, ranging from 20T to 60T (Tons of refrigeration).
Function Description
The HE Series Central Chillers are reliable, accurate, and easy-to-use process cooling units. They consist of a compressor, condenser, evaporator, metering device, and a control platform, all designed to maintain a stable tank temperature. The standard operating range for water-only applications is 50°F to 80°F (10°C to 27°C). For applications using a water/glycol mix in their pump tank, the range is 20°F to 50°F (-7°C to 10°C).
Typical applications include:
- Injection molding
- Blow molding
- Extrusion
- Thermoforming
- Machine tool
- Metal plating
- Thermal spray
- After-coolers (air compressors, dryers, etc.)
- Laser
- Printing (offset, gravure, digital)
The system is designed to operate with a minimum of one Master and one Drone module.
Important Technical Specifications
Models Covered:
- HECR-20T, HECR-25T, HECR-30T, HECR-40T, HECR-50T, HECR-60THEWC-20T (Remote Air-Cooled)
- HECW-25T, HECW-30T, HECW-40T, HECW-50T, HECW-60T (Water-Cooled)
Cooling Capacity (Tons / kW):
- 20T: 23.1 kW (81.2 MBH)
- 25T: 28.6 kW (100.5 MBH)
- 30T: 33.6 kW (118.2 MBH)
- 40T: 43.7 kW (153.7 MBH)
- 50T: 54.9 kW (193.1 MBH)
- 60T: 70.6 kW (248.3 MBH)
Condenser Water Flow (GPM / LPH) for Water-Cooled Models:
- 20T: 60 GPM
- 25T: 75 GPM
- 30T: 90 GPM
- 40T: 120 GPM
- 50T: 150 GPM
- 60T: 180 GPM
Dimensions (Height x Width x Depth in inches / cm):
- All models (20T-60T): 72(183) x 40(101) x 93(237)
Shipping Weight (Lbs / Kg):
- 20T: 1250(567)
- 25T: 1380(626)
- 30T: 1490(676)
- 40T: 2250(1020)
- 50T: 2450(1111)
- 60T: 2623(1190)
Electrical Features:
- Single-point power and ground connection per module.
- Non-fused disconnect switch, lockable per module.
- Branch circuit protection per module.
- Available voltages: (208-230/3/60), (380-460/3/60), (575/3/60 volt).
- UL/cUL Labeled Electrical Subpanel option available.
Refrigeration Features:
- HFC-410a refrigerant.
- High refrigerant pressure cutout switch (manual reset) at 575 psig.
- Suction and discharge pressure transducers.
- High refrigerant pressure spring-actuated relief valve.
- Modulating electronic expansion valve.
- Modulating hot gas bypass valve (for freeze protection and safeties only).
- Compressor crankcase heater.
Safety Devices and Interlocks:
- Crankcase Heater: Operates continuously when power is applied and compressors are off. Requires 24 hours of continuous power before initial startup to prevent compressor damage from dissolved refrigerant.
- High Pressure Cutout: Electro-mechanical device that opens the compressor control module if discharge pressure exceeds 575 psig. Manual reset required.
- Pressure Transducers: Two transducers (suction and discharge) monitor refrigeration pressures. Low suction pressure fault setpoint is derived from fluid freeze point temperature. Low discharge warning at 200 psig, fault at 180 psig.
- Flow Switch: Thermal dispersion flow switch shuts down the chiller if water/glycol flow rate through the evaporator drops below an acceptable level.
- Remote Start/Stop Interlock: Allows remote starting or stopping of the chiller via a switch or dry contact interlock.
- Remote Setpoint: Allows the chiller to be controlled to a setpoint sent to the PLC's configurable analog input.
Usage Features
Installation:
- Units are shipped on a skid, enclosed in plastic.
- Requires a concrete foundation, non-warping mounting pads, or a level floor capable of supporting the full operating weight. Must be level within ½ inch over its length and width.
- Chiller unit should be located indoors with accessibility for maintenance.
- Remote air-cooled condensers are installed outdoors, requiring a minimum clearance of 48 inches on all sides and 96 inches between condensers placed side by side.
- Proper refrigerant piping is crucial for remote air-cooled chillers, using hard/drawn type "L" or "K" AC&R copper tubing with a minimum burst pressure of 1,950 psi. Nitrogen charge must be relieved before cutting or brazing.
Operation:
- HMI color touchscreen (10-inch) on MASTER UNIT ONLY for control and monitoring.
- Password protection (Operator, Supervisor, Service) with 4-digit passwords.
- Chiller operation is determined by the pump tank temperature setpoint.
- Compressor anticycle and staging logic manage compressor operation for efficiency.
- Electronic Expansion Valve (EEV) controls refrigerant flow.
- Pump Down feature activates when the last active compressor is requested to stage off, to prevent liquid migration.
- Runtime meters track compressor operating hours.
- Network addressing allows multiple chiller modules (Master and Drones) to communicate.
- Alarms are logged and displayed on the HMI, with different categories (warnings, compressor critical faults, system critical alarms) and reset types (auto, user, auto until X times in Y seconds).
Fluid Considerations:
- Insulating all chilled water piping is recommended to prevent condensation.
- Galvanic corrosion: Non-ferrous piping (PVC) is recommended. If iron piping is used, dielectric unions and water treatment are required. Galvanized piping is discouraged.
- Water treatment is essential to prevent scale, erosion, algae, and corrosion.
- Glycol usage: For temperatures below 50°F (10°C), an inhibited ethylene glycol or propylene glycol and water solution is required to provide freeze protection 20°F (11°C) below the operating setpoint.
Maintenance Features
Technical Assistance:
- Parts Department: Call toll-free [800] 423-3183 or [262] 641-3950 (Fax [262] 641-8615) for genuine OEM parts.
- Service Department: Call toll-free [800] 423-3183 or [262] 641-3950 (Emergencies after 5pm CST, call [847] 439-5655). Service contracts available.
- Sales Department: Call [262] 641-3950 for independent sales representatives.
- Contract Department: Call [262] 641-3950 for project planning, system packages, and installations.
Preventative Maintenance Service:
- A systematic program is recommended to avoid downtime. Inspections include:
- Checking refrigerant suction and discharge pressures.
- Checking safety and operating conditions.
- Checking voltage and amperage of all motors.
- Checking all electrical connections.
- Checking quantity of refrigerant.
- Checking compressor oil level (for units with tandem compressors).
- Checking lubrication of motor and pump bearings.
- Checking circulating pump operation.
- Checking flow through heat exchangers.
- Checking compressor efficiency.
- Checking noise levels.
Specific Maintenance Tasks:
- Lubrication: Refrigeration compressors are hermetically sealed and require no lubrication.
- Condenser Maintenance:
- Remote Air-Cooled Chillers: Brush or vacuum dirt from aluminum condenser fins. Professional cleaning may be required for heavy accumulations.
- Water-Cooled Chillers (Shell & Tube): Clean dirt and slime from condenser tubes with a nylon tube brush. Remove mineral deposits by reverse circulating Liquid Inhibited Acid De-Scaling Solution (Part No. 216.00017.00). The refrigerant side is sealed and requires no routine maintenance.
- Evaporator Maintenance:
- Clean dirt and slime by reverse-circulating with a mild detergent and water solution.
- Remove mineral deposits by reverse-circulating Non-Acid De-Scaling Solution (Part No. 216.00017.00).
- Evaporator flush procedure: Close inlet/outlet butterfly valves, drain process fluid, connect isolated pumping system to upper/lower ball valves, operate until no visible debris, then flush with fresh water.
- Evaporator Process Strainer: Requires periodic cleaning. Close evaporator valves, drain, remove clip and sensor cap, remove strainer, clean, and replace. Operating without a strainer can plug the evaporator and void warranty.
Troubleshooting:
- The manual provides a detailed troubleshooting guide for alarms, warnings, and faults from the PLC, including possible causes and solutions (e.g., no power, wrong voltage, defective display, control circuit fuse blown, compressor internal overload, low water flow, low refrigerant charge, dirty condenser).
Software Updates and Settings Management:
- Updating C.pCO Program: Use a FAT32-formatted USB stick with an "UPGRADE" folder containing the Autorun.ap1 file. Save existing settings before updating, then restore them.
- Saving/Restoring Settings: Settings and configuration variables can be saved or loaded from internal PLC memory or a USB stick (FAT32 format). Hour meters can be included.
- Updating Exor HMI Program: Use a FAT32-formatted USB stick with the UpdatePackage.zip file. Access the update wizard from the HMI screen.
- Downloading Alarm History/Chiller Logs: Alarm history and chiller logs (SPs, staging, status) can be downloaded to a USB stick from the HMI.
- Changing Exor IP Address: Instructions provided for accessing system settings on the HMI to modify the IP address and Netmask.
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