Portable Chillers VL Series Air-Cooled and Water-Cooled with Capacities from 2 to 40 tons Installation Maintenance Operation Troubleshooting The Conair Group, Inc. One Conair Drive Pittsburgh, PA 15202 Phone: (412) 312-6000 Fax: (412)-312-6227 UGH021/0301 WARNING - Reliance on this Manual Could Result in Severe Bodily Injury or Death! This manual is out-of-date and is provided only for its technical information, data and capacities.
Please record your equipment’s model and serial number(s) and the date you received it in the spaces provided. It’s a good idea to record the model and serial number(s) of your equipment and the date you received it in the User Guide. Our service department uses this information, along with the manual number, to provide help for the specific equipment you installed. Please keep this User Guide and all manuals, engineering prints and parts lists together for documentation of your equipment.
TABLE OF CONTENTS 1.0 GENERAL 1.1 Introduction 1.2 Unit location for air cooled models 1.3 Unit location for water cooled models 1.4 Efficiency 1.5 Safety 1.6 Clean air act 1.7 Miscellaneous Chiller features identified 5 6 6 6 6 7 7 7 8 2.0 INSTALLATION 2.1 General 2.2 To and From process connections 2.3 Water supply connection 2.4 Air cooled condenser 2.4 Water cooled condenser 2.5 Electrical connection 9 10 10 11 11 13 13 3.0 OPERATIONS 3.1 General 3.2 Start up/operations procedure 3.
Page: 4 7.0 RELATED DRAWINGS 7.1 VLA-5/7.5/10 mechanical schematic 7.2 VLA-15/20/25/30 mechanical schematic 7.3 VLA-5 physical 7.4 VLA-7.5/10 physical 7.5 VLA-15/20/25/30 physical 7.6 Duct schematic for air cooled chillers 7.7 VLA-5/ 7.5/ 10 electrical 7.8 VLA-15/ 20/ 25/ 30 electrical 7.9 VLW-5/7.5/10 ton mechanical schematic 7.10 VLW-15/20/25/30 ton mechanical schematic 7.11 VLW-5/7.5/10 physical 7.12 VLW-15/20/25/30 ton physical 7.13 VLW-5/ 7.5/ 10 ton electrical 7.
1.0 GENERAL 1.1 1.2 1.3 1.4 1.5 1.6 1.
1.1 1.2 1.3 INTRODUCTION A. This manual covers most ‘VL’ series portable chiller models. Most ‘VL’ series portable chillers are basically identical with exception of the type of condenser (air cooled or water cooled). B. All instructions in this manual apply to most ‘VL’ series portable chiller models regardless of the type of condenser or instrumentation.
quality. Conair recommends filtering where required to prevent solids from plugging critical parts (pumps, heaters, seals for example). Conair highly recommends the services of a competent water treatment specialist be obtained and his recommendations followed. Conair accepts no responsibility for inefficient operation, or damage caused by foreign materials or failure to use adequate water treatment. 1.5 1.6 1.7 UGH021/0301 SAFETY A.
Air Cooled Condenser Fiberglass Fan Shroud To Process Connection Fan Motor From Process Connection Galvanized Steel Frame Hot Gas Bypass Valve Electrical Cabinet VLA-10 pictured Centrifugal Pump Insulated Fiberglass Reservoir Compressor Refrigerant Sight Glass Expansion Valve Liquid Line Solenoid Filter-Drier Caster To Process Connection From Process Connection Insulated Fiberglass Reservoir Expansion Valve Refrigerant Sight Glass Galvanized Steel Frame VLW-10 pictured Condenser Return Co
2.0 INSTALLATION 2.1 2.2 2.3 2.4 2.5 2.
2.1 2.2 GENERAL A. All process piping materials (such as hose, rigid piping, valves or filters) used in process water piping circuitry must be rated for 100°F minimum temperature and 100 PSI minimum pressure. B. All such materials must have the equivalent or larger diameter of the particular process connection that length of process water piping is connected to. TO AND FROM PROCESS CONNECTIONS (see figures 2.2A & 2.2B) A. Connect the ‘TO PROCESS’ to the ‘water in’ manifold on the mold or process. B.
To process connection: connect to “water in” on process manifold From process connection: connect to “water out” on process manifold Water supply connection: (not shown on this unit) connect to city water source Typical process connections for air cooled chiller 2.3 WATER SUPPLY CONNECTION A. 2.4 The automatic water supply make-up system continually monitors the reservoir tank and fills it when needed. Connect as follows: 1. Connect the chiller’s ‘WATER SUPPLY’ port to the plant’s city water source.
B. C. A free air space of at least two (2) feet is required at the condenser intake and six (6) feet at the condenser discharge to allow for proper air flow. D. At full load, the chiller will discharge approximately 15,000 BTU’s per hour per ton of cooling. E. F. Page: 12 Air flow is generated by the motor driven fans (figure 2.4A) or centrifugal blowers (figure 2.4B). Air flow is from the outside of the chiller, through the condenser and exhausted through the top of the unit.
2.5 WATER COOLED CONDENSER CONNECTION A. B. Connect the ‘CONDENSER WATER IN’ port to the plant’s city water supply or tower system supply. 1. Required consumption from a city water source is 1.5 gpm at 65°F per ton of rated capacity. 2. Required consumption for a tower water source is 3 gpm at 85°F per ton of rated capacity. Condenser connections 10 ton unit- optional regulator valve shown Figure 2.5B Note: if dumping to the plant’s open drain, drainage shall be done according to local codes. C.
cause a significant hazard that may result in serious personal injury and unit damage. B. 2. A customer supplied, four conductor cable is required for connection to a customer supplied fused disconnecting means. The fused disconnecting means shall be sized and installed according to the unit’s power supply requirements and local electrical codes. See figure 2.5A (next page) for details on water cooled power cable routing. 3.
3. Make certain all electrical connections are tightly affixed. Any loose wiring connections must be tighten before engaging the power supply. 4. Make certain no moisture or standing water is present inside the electrical cabinet (figure 2.5B).
THIS PAGE INTENTIONALLY BLANK Page: 16 VL Series Portable Chillers, 2 to 40 Tons UGH021/0301
3.0 OPERATIONS 3.1 3.2 3.3 3.
3.1 3.2 GENERAL A. Failure to follow the factory required operations procedure may adversely affect the unit’s ability to adequately control process temperature and may create a hazardous operating condition which may result in serious operator injury and/or unit damage. B. IMPORTANT: each chiller is equipped with a crankcase heater on the compressor. While the compressor is idle, the crankcase heater prevents freon vapor from migrating to and condensing in the compressor crankcase.
2. Conair recommends the addition of 20% inhibited propylene glycol to the process fluid. This should help prevent the process fluid from freezing and internal components from rusting. A biocide must be added to the water to prevent organism growth in the chilled water system. See water treatment section in section 8 of this manual for more information. 3. FOR AUTOMATIC FILL (IF EQUIPPED): engage the water supply to unit. The level switch will activate the make-up solenoid (figure 3.
2. Page: 20 d. Toggle the CHILLER ON switch. This will quickly cycle the electrical motor “on” and then “off”. e. Observe the motor shaft. When the CHILLER ON switch is turned “on”, the Electric motor Figure 3.2B motor shaft will Pump rotate. When the CHILLER ON switch is turned “off”, the motor shaft will slowly “coast” to a stop. As the shaft slows to a stop, the operator must identify its rotation. Correct rotation (correct phase) is “clockwise”, when Motor shaft Figure 3.
power supply. The operator must reverse the power leads at the disconnect switch only and NOT at the power entry terminals on the unit’s electrical panel. The unit’s internal electrical system wiring is phased correctly at the factory and must not be altered in the field. d. C. Visually inspect the rotation of the motor as outlined step 1 to determine the unit is phased correctly. PROCESS FLOW ADJUSTMENTS 1.
4. EXCESSIVE FLOW... excessive flow can overload the process pump motor and cause eventual failure. This is a result of the process loop’s ability to flow water at a great rate than can be provided by the process pump. This eventually results in tripping the thermal motor overload relay (overload relays open) and the unit will shut down. a. 5. Figure 3.
3.3 f. The amp meter will display the motor amps. Compare the actual motor amps as displayed on the amp meter to the full load amp rating as listed on the motor name plate. g. If the amp draw is excessive (higher than the listed name plate amp rating), a throttling valve must be installed in the “from process” circuit line. The preferred throttling valve is a ball valve. h. With the throttling valve installed, fully close the valve and then engage the pump.
determines an indicating light or digit does not illuminate, the instrument must be removed and sent to the factory for repair. When power is supplied to the unit, the POWER light will illuminated. Page: 24 3. Toggle ‘on’ the CHILLER ON rocker switch to activate the chiller. The operator can stop process operations (refrigerant and coolant circuits) by switching ‘off’ the CHILLER ON switch. 4.
B. C. D. UGH021/0301 INSTRUMENT OPERATION 1. When the CHILLER ON rocker switch is toggled on, the instrument will begin temperature control operations and the ‘to process’ temperature will begin to drop. 2. When the ‘to process’ temperature drops 1° below the setpoint, the instrument will activate the capacity control system to match the cooling capacity to the present load, as indicated by the HOT GAS BYPASS light (figure 3.3A). 3.
the compressor contactor. Engaging the compressor contactor supplies electrical current to the compressor. This action will decrease process water temperature. 4. E. TEMPERATURE DISPLAY 1. 3.4 A three digit display window indicates the appropriate temperature in Fahrenheit. The window also displays the numeric value for the setpoint temperature. A red light will illuminate beside the parameter currently being displayed. a. TO PROCESS: indicates liquid temperature being delivered from the chiller. b.
4.0 TROUBLESHOOTING 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.
4.1 4.2 4.3 4.4 4.5 Page: 28 SENSORS A. The sensor is a solid state temperature transducer which converts temperature input to proportional current output. B. To quickly test for a defective probe, switch connections between the defective probe and a probe known to be working properly. PROCESS PUMP A. The centrifugal pump is designed to operate at a specific flow and pressure at the maximum run load amp draw of the motor.
4.6 4.7 4.8 HIGH PRESSURE A. If the refrigerant high pressure safety switch has opened, this switch must be manually reset after the problem has been resolved. B. Refrigerant high pressure will vary with ambient temperature from a minimum of 190 psi to as high as 280 psi. Check for restricted filters, broken or loose blower drive belts, restricted air flow. C. On air-cooled models: maintain at least four feet of clearance for each condenser intake. D.
port. If the water out temperature of the evaporator reaches the freezestat setting the switch will open and stop the refrigeration compressor. 4.9 4.10 B. Check for restricted water flow and add a bypass line if necessary. C. The setpoint is adjusted too low for the safety switch settings. D. The freezestat is adjusted incorrectly or is defective. OIL PRESSURE (Semi-hermetic Compressors) A. This switch must be manually reset after the problem is resolved. B.
5.0 MAINTENANCE 5.1 5.2 5.3 5.4 5.5 5.6 5.
5.1 5.2 WARRANTY SERVICE PROCEDURE A. In the event of a problem with a chiller that can not be resolved by normal troubleshooting procedures, the customer is invited to consult the Conair service department for assistance. The correct model number and serial number of the chiller must be available. The service department will attempt to isolate the problem and advise repair procedures.
5.3 I. Refrigerant sight glass: check for bubbles when compressor is operating at 100%. Check the moisture indicator for a color other than green. J. Clean unit. SPECIAL MAINTENANCE A. UGH021/0301 Any service of the refrigeration system must be accomplished by a certified refrigeration technician. 1. Vacuum check compressor. 2. Addition of compressor oil. 3. Addition of refrigerant. 4. Repair of a refrigerant leak. 5. Adjustment of super heat. 6. Changing of filter-drier or drier core. 7.
5.4 SOLENOID VALVE SERVICE A. VLA units with the water make-up system use a solenoid valve (figure 5.4A) to regulate the level in the reservoir tank. The solenoid valve is controlled by the float switch. B. Generally, solenoid valves fail due to poor water quality, low water flow, or defective valve elements. C. The operator should follow this procedure to service the make-up solenoid valve: Typical water make-up solenoid valve Figure 5.4A 1.
screen and clean or replace as necessary. 9. Clean the valve body. 10. Reset the mesh screen into the valve body. 11. If a new diaphragm assembly was obtained, continue with step 12. If not, disassemble the diaphragm assembly and note component order (figure 5.4E). Clean the valve port, plate, collar and O-ring. Once cleaned, reassemble the diaphragm. 12. Top bonnet Enclosure tube Diaphragm assembly Set the reassembled diaphragm assembly or the new assembly back into the valve body.
5.5 PUMP SEAL SERVICE A. The VLA unit pump seal is a carbon/niresist shaft seal assembly including a stationary member, rotating member and tension spring (figure 5.5A). B. The operator can determine the pump seal is leaking when fluid is identified leaking from the pump case adapter. Generally, a pump seal will leak due to inadequate unit pressure, excessive flow and poor fluid quality. Tension Spring Rotating Member Figure 5.5A Stationary member C.
6. Locate and remove the pump casing bolts. These bolts secure the motor and motor adapter to the pump casing (figure 5.5D). 7. Separate the motor and motor adapter from the pump casing to expose the pump impeller (figure 5.5E). Remove the motor and motor adapter from the unit and place on a workbench to continue the procedure. 8. 9. UGH021/0301 Locate and remove the dust cap from motor end to expose slotted motor shaft. The motor shaft is free to rotate, but must be secured to remove the impeller.
The operator must be certain the stationary seal member is fully squared and seated in cavity. 13. 14. Place the spring onto the rotating member. 15. Align the impeller, spring and rotating member before reinstalling the impeller (figure 5.5K). The operator must be certain the spring and rotating member are aligned before the impeller is fully tighten and the impeller retaining screw is reinstalled. 16. Clean pump casing, cavities, impeller and Oring before reassembly. 17.
5.6 CHECKING THE REFRIGERANT CHARGE A. All standard Conair chillers are manufactured with thermostatic expansion valves as the metering device to the evaporator. B. All Conair chillers have a refrigerant sight glass with a moisture indicator. To check the refrigerant charge under normal operating conditions: 1. Remove the plastic cap covering the sight glass, if installed. 2. Start the chiller and allow system pressures and temperatures to stabilize. 3.
5.7 PROPER CLEANING PROCEDURE FOR BRAZED PLATE EVAPORATORS A. The brazed plate evaporator is made of stamped stainless steel plates, furnace brazed together with copper based joints. The complex geometry of the flow passages promotes turbulent flow which gives high efficiency and reduces fouling by mineral deposits. Large solids such as plastic pellets or chunks of mineral deposits will collect at the water Typical evaporator installation Figure 5.
C. UGH021/0301 Backflushing procedure: 1. Turn off all power to the machine. For chillers with a reservoir tank, drain the tank to below the evaporator outlet. For chillers without a reservoir tank, drain total unit. 2. Connect a water supply hose to the evaporator water outlet. If acid cleaning, connect the discharge hose from the acid pump to the evaporator outlet port. 3. Connect a hose to the evaporator water supply port and to an appropriate containment vessel.
THIS PAGE INTENTIONALLY BLANK Page: 42 VL Series Portable Chillers, 2 to 40 Tons UGH021/0301
6.0 COMPONENTS 6.1 6.
6.1 6.2 WATER SYSTEM A. MOTOR/PUMP ASSEMBLY: the motor/pump assembly circulates chilled fluid to the process loop. The pump assembly is built of total stainless steel to maintain water quality (figure 6.1A). B. FREEZESTAT: the freezestat aids in protecting the evaporator from potential freezing. The freezestat is factory adjusted to 40°F. The freezestat must be field adjusted for operating with setpoints below 48°F (figure 6.1B). Pump Figure 6.1A REFRIGERATION SYSTEM A.
C. FILTER-DRIER: the filter-drier removes contaminants and moisture from the liquid refrigerant (figure 6.2C). D. LIQUID LINE SOLENOID VALVE: controlled by the instrument, this valve closes when the compressor cycles off to prevent refrigerant liquid from migrating to the evaporator. The valve opens when the compressor cycles on (figure 6.2D). E. E. UGH021/0301 REFRIGERANT SIGHT GLASS: the refrigerant sight glass indicates refrigerant charge and moisture content.
H. I. HIGH/LOW PRESSURESTATS: the high/low pressurestats protect the refrigeration system from unsafe operating levels. The high pressure switch is factory set to open at 325 psi and protects the refrigeration components and personnel from potential damage of injury from excessive high pressure. The high pressure safety must not be altered in the field for any reason. The low pressure switch is factory set to open at 58 psi and to close at 63 psi.
7.0 RELATED DRAWINGS 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10 7.11 7.12 7.13 7.14 UGH021/0301 VLA-5/7.5/10 MECHANICAL SCHEMATIC VLA-15/20/25/30 MECHANICAL SCHEMATIC VLA-5A PHYSICAL VLA-7.5/10 PHYSICAL VLA-15/20/25/30 PHYSICAL DUCT SCHEMATIC FOR AIR COOLED CHILLERS VLA-5A/7.5/10 ELECTRICAL VLA-15/20/25/30 ELECTRICAL VLW-5/7.5/10 MECHANICAL SCHEMATIC VLW-15/20/25/30 MECHANICAL SCHEMATIC VLW-5/7.5/10 PHYSICAL VLW-15/20/25/30/40 PHYSICAL VLW-5/7.
Page: 48 VL Series Portable Chillers, 2 to 40 Tons FILTER-DRIER LIQUID LINE RECEIVER COMPRESSOR (may be Scroll Hermetic or Recip) LIQUID LINE SOLENOID VALVE HIGH PRESSURE SAFETY SWITCH REFRIGERANT SIGHT GLASS HOT GAS BYPASS VALVE EXPANSION VALVE COOLANT PUMP EVAPORATOR RESERVOIR TANK LOW PRESSURE SAFETY SWITCH AIR-COOLED CONDENSER w/FANS (5-ton model uses single fan) (optional) TO PROCESS SENSOR PROBE FROM PROCESS PORT CONNECTION TO PROCESS PORT CONNECTION MAKE-UP PORT CONNECTION (optional
UGH021/0301 VL Series Portable Chillers, 2 to 40 Tons FILTER-DRIER LIQUID LINE RECEIVER COMPRESSOR (may be Scroll Hermetic or Recip) LIQUID LINE SOLENOID VALVE HIGH PRESSURE SAFETY SWITCH REFRIGERANT SIGHT GLASS HOT GAS BYPASS VALVE EXPANSION VALVE COOLANT PUMP EVAPORATOR RESERVOIR TANK LOW PRESSURE SAFETY SWITCH AIR-COOLED CONDENSER w/blower (optional) TO PROCESS SENSOR PROBE FROM PROCESS PORT CONNECTION TO PROCESS PORT CONNECTION MAKE-UP PORT CONNECTION (optional) LEVEL SWITCH (optional
7.
7.4 VLA-7.
7.
7.
Page: 54 Hot Gas Bypass Compressor Pump Power VL Chiller Control TO PROCESS PROBE Temperature Setpoint To Process VL Series Portable Chillers, 2 to 40 Tons Off On GRN 20 BRN 8 9 WHT ORG 50 24 HIGH PRESSURESTAT 26 23 BLU 22 22 26 22 22 1 MOL 19 12 26 26 25 22 22 19 FU 2 12 3 CRANKCASE HEATER 11 RED/WHT 25 9 M2 10 FU 1 22 21 F1 9 FAN MOTOR #2 REQUIRED ON 7.5 & 10 TON 7 7 1 22 FREEZESTAT 21 9 FAN MOTOR 9 POWER ENTRY L4 F2 L3 OPTIONAL CUST.
UGH021/0301 Hot Gas Bypass Compressor Pump Power VL Chiller Control TO PROCESS PROBE Temperature Setpoint To Process Off On GRN MOLEX 20 21 RED/BLU RED/YEL 24 RED/WHT VL Series Portable Chillers, 2 to 40 Tons 29 31 RED/BLK ORG 35 28 RED/ORG BRN 27 BLU 50 23 RED/BRN 19 JUMPER 19 RED WHT 5A 6A 19 LOW PRESSURESTAT FREEZESTAT 35 29 29 M3 8 2 3 9 30 HIGH PRESSURESTAT 29 7 1 21 4 MOL COMPRESSOR M3 OPTIONAL CUST. SUPPLIED CONTACTS FOR REMOTE START/STOP.
Page: 56 VL Series Portable Chillers, 2 to 40 Tons LIQUID LINE SOLENOID VALVE COMPRESSOR HIGH PRESSURE SAFETY SWITCH FILTER-DRIER REFRIGERANT SIGHT GLASS HOT GAS BYPASS VALVE EXPANSION VALVE LOW PRESSURE SAFETY SWITCH WATER COOLED CONDENSER RESERVOIR TANK COOLANT PUMP EVAPORATOR CONDENSER WATER OUT PORT CONNECTION CONDENSER WATER IN PORT CONNECTION WATER REGULATOR VALVE MAKE-UP SOLENOID VALVE (OPTIONAL) TO PROCESS SENSOR PROBE FROM PROCESS PORT CONNECTION TO PROCESS PORT CONNECTION MAKE
UGH021/0301 VL Series Portable Chillers, 2 to 40 Tons LIQUID LINE SOLENOID VALVE COMPRESSOR HIGH PRESSURE SAFETY SWITCH FILTER-DRIER WATER COOLED CONDENSER REFRIGERANT SIGHT GLASS HOT GAS BYPASS VALVE EXPANSION VALVE LOW PRESSURE SAFETY SWITCH RESERVOIR TANK COOLANT PUMP EVAPORATOR WATER REGULATOR VALVE TO PROCESS SENSOR PROBE FROM PROCESS PORT CONNECTION TO PROCESS PORT CONNECTION MAKE-UP PORT CONNECTION (OPTIONAL) LEVEL SWITCH (OPTIONAL) MAKE-UP SOLENOID VALVE (OPTIONAL) SERVICE LID
7.11 VLW 5/7.
7.
Page: 60 Hot Gas Bypass Compressor Pump Power VL Chiller Control TO PROCESS PROBE Temperature Setpoint To Process Off On GRN 20 BRN 8 9 L3 WHT 50 24 26 HIGH PRESSURESTAT 26 23 BLU ORG 22 22 22 25 22 RED/WHT 1 MOL 12 26 26 25 22 22 19 FU 2 12 3 CRANKCASE HEATER 11 M2 10 FU 1 1 22 21 POWER ENTRY L4 22 FREEZESTAT 21 OPTIONAL CUST. SUPPLIED CONTACTS FOR REMOTE START/STOP.
UGH021/0301 Hot Gas Bypass Compressor Pump Power VL Chiller Control TO PROCESS PROBE Temperature Setpoint To Process Off On GRN MOLEX VL Series Portable Chillers, 2 to 40 Tons 50 24 ORG 22 RED/WHT 23 22 RED/BRN BLU 21 JUMPER 20 BRW RED/YEL 19 RED WHT 7 8 9 3 19 FREEZESTAT HIGH PRESSURESTAT OPTIONAL CUST. SUPPLIED CONTACTS FOR REMOTE START/STOP.
THIS PAGE INTENTIONALLY BLANK Page: 62 VL Series Portable Chillers, 2 to 40 Tons UGH021/0301
8.0 APPENDIX 8.1A 8.1B 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 8.10 8.11 8.
8.1 SPECIFICATIONS VLA MODELS, 2 TO 30 TONS MODEL Performance characteristics Capacity* ton Compressor Hp {kW}✝ Pump Hp {kW} Process flow‡ gpm {lpm} Process pressure§ psi {bar} Reservoir capacity gal {liters} Condenser assembly type Condenser fan power Hp {kW} Condenser air flow ft3/min {liters/min} Condenser static pressure, in. H20 Dimensions in {mm} Height Width Depth Pipe size NPT in.
VLW MODELS, 2 TO 40 TONS MODEL VLW-2 VLW-3 Performance characteristics Capacity* ton 2 3 Compressor Hp {kW} 2 {1.5} 3 {22} Pump Hp {kW} 0.75 {0.56} 0.75 {0.56} Chilled water flow✝ gpm {lpm} 4.8 {18} 7.2 {27} Chilled water pressure✝ psi {bar} 40 {2.76} 39 {2.69} Reservoir capacity gal {liters} 15 {56.8} 15 {56.8} Compressor type Hermetic Hermetic Condenser water requirements ‡ City gpm {lpm} 6 {23} 9 {34} Tower gpm {lpm} 3 {11} 4.
8.2 OPERATION BELOW 48°F A. A chiller typically operates with a setpoint of 50°F or higher. However, if setpoints between 20° - 48°F are required, special precautions must be taken to prevent freezing and possible damage. Attention must be given to freeze protection, water supply and safety adjustments. B. FREEZE PROTECTION 1. It is understood that untreated water freezes at 32°F. Therefore, an inhibited propylene glycol and water solution must be used in lieu of ordinary water.
decreasing the freeze protecting ability of the solution. Therefore, the water supply source must be disconnected and the connection capped. The operator must monitor the water/glycol level and manually make-up to maintain proper reservoir level. D. SAFETY ADJUSTMENTS 1. To ensure safe and efficient operations at lower setpoints, adjustments of the freezestat and low pressurestat factory settings are required. Figure 8.2B lists the appropriate settings. Figure 8.2B E. 2.
8.3 8.4 WATER QUALITY CONTROL A. Lack of, as well as, improper water treatment can damage the chilling unit. The services of a competent water treatment specialist should be obtained and their recommendations followed. It is the equipment owner’s responsibility to prevent damage from foreign material or inadequate water treatment. B. The two main things to consider for water treatment in chillers are corrosion and organism growth. Proper chemical treatment can control PH levels and algae growth.
C. USE OF PLAIN GLYCOL: 1. D. AUTOMOTIVE BASED ANTIFREEZE: 1. E. SHOULD NEVER BE USED! Automotive antifreeze contains silicate based inhibitors, which are compatible with automotive components. In an industrial application, the silicates will leach out and form a gel-like substance on the heat transfer surfaces and reduce cooling efficiency of the system. These silicates have shown to significantly reduce the lifetime of pump seals. MAINTENANCE RESPONSIBILITY: 1.
8.5 MAINTAINING PROPER WATER FLOW A. B. The evaporator in a typical water chiller is flow sensitive. That is, the efficiency of operation is directly related to the flow of liquid. Maximum efficiency is obtained at approximately 2.4gpm per ton of rated capacity. Low liquid flow can reduce efficiency and in some cases allow ice to form in the evaporator which can damage the evaporator.
8.6 LOW FLOW BYPASS CIRCUITS A. In cases of restricted flow or reduced capacity conditions, as an option Conair supplies manual or automatic low flow bypass circuits on water cooled or air cooled portable chillers. It is recommended that where low flow conditions exist, a bypass system be installed either in the field or by Conair. It is the ultimate responsibility of the user to make sure adequate flow through the evaporator is achieved. B.
8.7 OVERHEAD PIPING KIT A. Conair portable chillers have between a 4.5 to 60 gallon reservoir capacity (depending on chiller size). When a Conair portable chiller is used with overhead piping, the chiller tank will overflow upon shut-down due to the drainback of water volume from the overhead piping system (which exceeds the tank capacity of the chiller). If the piping arrangement is not above the chiller tank level, then this problem will not exist. B.
8.8 CHILLER CAPACITY AND DERATE CHART Standard chiller rating is at 50°F. For all other temperature settings, output tonnage is altered as follows: OUTPUT FULL TEMPERATURE AVAILABLE % °F CAPACITY 60 105% 50 100% 45 90% 40 80% 35 70% 30 60% 25 50% 20 40% * 15 30% * 10 22% * 5 15% * 0 9% * -5 5% NOTES: If operation of the chiller at less than 48°F is required, an inhibited propylene glycol solution is required. Consult factory for chiller operation below 20°F.
8.9 PRESSURE-TEMPERATURE CHART FOR R-22 REFRIGERANT SATURATED TEMPERATURE FREON PRESSURE 40°F 68 45°F 76 50°F 84 55°F 93 60°F 100 65°F 112 70°F 122 75°F 132 80°F 144 85°F 156 90°F 168 95°F 182 100°F 196 THESE PRESSURE/TEMPERATURE RELATIONSHIPS ARE IN AN AT-REST, SATURATED CONDITION.
8.10 1 ton BTU 1 BTU 1 watt 1 KW 1 KW BTU/hr = = = = = = = TONS = TONS = ENGINEERING FORMULAS 12,000 btu Material (lbs) X material 's specific heat X temperature difference .293 watts 3.42 BTU 1000 watts 3420 BTUs GPM X T (for water cooled condensers) GPM (water) X 8.34 X 60 X temperature difference X specific heat 12,000 GPM (water) X T 12,000 1 Gallon of Water = = = = = = = = 1 Pound of Water 1 Cubic foot of Water 8.34 lbs 231 cubic inch .1337 cubic feet 3.785 liters 4 quarts .1198 gallon 7.
8.
8.
THIS PAGE INTENTIONALLY BLANK Page: 78 VL Series Portable Chillers, 2 to 40 Tons UGH021/0301
Conair has made the largest investment in customer support in the plastics industry. Our service experts are available to help with any problem you might have installing and operating your equipment. Your Conair sales representative also can help analyze the nature of your problem, assuring that it did not result from misapplication or improper use.
EQUIPMENT GUARANTEE Conair guarantees the machinery and equipment on this order, for a period as defined in the quotation from date of shipment, against defects in material and workmanship under the normal use and service for which it was recommended (except for parts that are typically replaced after normal usage, such as filters, liner plates, etc.). Conair’s guarantee is limited to replacing, at our option, the part or parts determined by us to be defective after examination.
