NTRODUCTION System Descriptions Himod environmental control systems are available in several main system configurations: Air Cooled, Glycol Cooled, GLYCOOL, Dual Cool With Air and Dual Cool With Glycol. All types have a single scroll compressor and are available in upflow and downflow configurations. The standard upflow configuration is front return.
Locate the Start-Up form supplied with your unit documents. Complete the form during your start-up and mail it to Liebert when start-up is completed. Contact your Liebert supplier if you have any ques- tions or problems during your unit installation, start-up or operation.
ICROPROCESSOR ONTROLS The Advanced Microprocessor (A) Control for your Liebert Himod unit features an easy-to-use menu driven LCD display. The menus, control features, and circuit board details are described in this sec- tion. For more control details, refer to 4.0 - System Performance with Advanced Microproces- sor Controls, and for more alarm information, refer to 5.0 - Alarm Descriptions.
Figure 2 Advanced microprocessor (a) control for Himod Main Menu 72°F 50%RH Normal Display Status/Alarm Data Cooling Setpoints/Setup Dehumidifying Date and Time No Alarms Present Status Display Status Alarm Data Setpoints/Setup Date and Time Status Display Active Alarms View Setpoints 15-APR-2001 09:30:00 75°F 59%RH...
Status Display The display normally shown includes the present room temperature, humidity, active status func- tions (cooling, heating, dehumidifying, humidifying), and active alarms. If no keys are pressed for five minutes, the system automatically returns to the Status Display. The Status Display may also be selected from the Main Menu.
2.4.4 Run Hours Log The total operating hours of all major components in the unit can be monitored from the display and are retained in nonvolatile memory. Run times are available for the following: • Compressor • GLYCOOL Coil (or CW Coil as used on Dual Cooling Unit) •...
The message “Restart Delay -- Please Wait” will be displayed when the system is in the auto restart mode. Liebert suggests multiple unit installations be programmed with different auto restart times.
Dual Cooling Not Used Challenger 3000 Himod The selections shown in Table 4 should match options installed on your unit and should not need to change during normal operation. Switches 1 through 7 are self explanatory. DIP switch 8, not shown in the table, enables the password feature when set to ON and disables the password feature when set to OFF.
Setup Alarms Selecting SETUP ALARMS will step to the following menu: • SET TIME DELAYS • ENABLE ALARMS • ENABLE COMMON ALARM • SET CUSTOM ALARMS Each individual alarm can be programmed with a time delay from 0 to 255 seconds. Each individual alarm can be ENABLED or DISABLED and each individual alarm can be programmed to energize or not to energize the Common Alarm Relay.
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Set Custom Alarms. The custom alarm messages can be from a list of standard alarm messages or you can write your own message. NOTE A maximum of two of the alarm messages can be your own message. They can be in any location(s) 1 through 4. The text for custom alarms can be changed at any time by selecting “SET CUSTOM ALARMS”.
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Analog Setup For installation of analog sensors, see 4.5.1 - Connecting the Analog Sensors. After selecting a compatible sensor and properly wiring it to the terminals, set up the control to mon- itor the sensor as follows: Slope. The slope is a multiplier used to scale the input signal. The slope can be positive (rising) or negative (falling) and can range from 0 (resulting in a horizontal line) to ±999.
2.5.3 Run Diagnostics By selecting Run Diagnostics, maintenance personnel can check system inputs, outputs, and complete a test of the microcontroller circuit board, all from the front panel. Review of the system inputs and the microcontroller test can be done without interrupting normal operation. To test the system out- puts, the normal system control is temporarily suspended.
2.5.4 Change Passwords The display prompts you to enter a three digit password when making changes. The system includes two (2) passwords, one for setpoints and one for setup. The system allows the passwords to be changed by first entering the present password, factory set as “123” for setpoints and “321” for setup. The pass- word function provides system security, so only personnel authorized to make changes should know the passwords.
Control Circuit Board The control circuit board is located inside the unit behind the LCD display and control key panel. Open the front panel for access to the board. The control board includes an adjustment for LCD display contrast, nonvolatile memory, DIP switches (which should not require customer changes), control output LEDs and jumpers for board configuration.
RAPHICS ONTROL The Advanced Microprocessor with Graphics (G) Control for your Liebert Himod unit features an easy to use menu driven LCD Graphics Display. The menus, control features, and circuit board details are described in this section. For more details on the control refer to 4.0 - System Performance with Advanced Microprocessor Controls;...
Use / to locate file Modify Humidity Scales Use ENTER to Modify Analog Sensor define file # 1 Scale ** Optional # 2 Scale *** Himod units only # 3 Scale # 4 Scale Operation with Advanced Microprocessor with Graphics Control...
Status Display The normal status screen is divided into two sections, a right half and a left half. The left half displays the return air temperature and humidity readings in large characters. NOTE The display can also be set to display the temperature and humidity setpoints. See 3.7.6 - Set Status Display.
3.4.2 Alarm History Log A history of the sixty (60) most recent alarms is kept in nonvolatile memory complete with the type of alarm, the alarm name, and the date and time of its occurrence. The first alarm in the history is the most recent and the last (up to 60) is the oldest.
3.4.4 Setup Custom Alarms Selecting SETUP CUSTOM ALARMS will step to the following menu: • SETUP CUSTOM ALARM TEXT • CHANGE CUSTOM TEXT 1 • CHANGE CUSTOM TEXT 2 • CHANGE CUSTOM TEXT 3 • CHANGE CUSTOM TEXT 4 The custom alarm messages can be selected from a list of standard messages or you can write your own messages.
Operating Status The Operating Status is intended to provide the user with displayed information concerning what the control is calling for the system to do. NOTE There may be some time lapse before a specific component matches the displayed number. For example: The display indicates the chilled water valve (from Econ-O-Coil) is 68% open.
The message “Restart Delay -- Please Wait” will be displayed when the system is in the auto restart mode. Liebert suggests multiple unit installations be programmed with different auto restart times.
3.7.4 Calibrate Valve Actuator For systems that use a valve actuator for chilled water or GLYCOOL cooling, the actuator timing may be calibrated or adjusted. This is the time it takes for the valve to travel from full closed to full open. It is programmable from 0 to 255 seconds.
Run Diagnostics By selecting RUN DIAGNOSTICS, maintenance personnel can check system inputs, outputs, and complete a test of the microcontroller circuit board, all from the front panel. Review of the system inputs and the microcontroller test can be done without interrupting normal operation. 3.8.1 Show Inputs With the unit on and the fan running, the input state for the following devices may be displayed:...
Dual Cooling Not Used Challenger 3000 Himod Date and Time The current date and time is available through the display. This feature allows the date and time to be read or changed and is accessed by selecting “DATE AND TIME” from the Main Menu. The “DATE AND TIME”...
3.11 Analog/Digital Inputs Selecting ANALOG/DIGITAL INPUTS steps to the following menu: • READ ANALOG INPUTS • SETUP ANALOG INPUTS • READ DIGITAL INPUTS • SETUP DIGITAL INPUTS 3.11.1 Read Analog Inputs The four (4) analog sensor inputs can be monitored from the display. The inputs are filtered, then dis- played along with the text label assigned during setup.
3.12 View Run Hours Log Selecting VIEW RUN HOURS LOG will step to the following menu: • VIEW 24 HOUR RUN TIME HISTORY • VIEW TOTAL RUN HOURS 3.12.1 View 24 Hour Run Time History The history of each load for every hour during the past 24 hours is displayed in the run hour history. The percentage of each hour that the load was on is displayed from 0 to 100% in increments of 5% or 3 minutes.
3.13.1 LCD Display Contrast The level of contrast due to the viewing angle of the LCD display can be adjusted using a small thumb wheel at the upper left of the control board just under the cable going to the display. The control is labeled RA1.
ERFORMANCE WITH DVANCED ICROPROCESSOR ONTROLS This section provides details on how your Himod unit responds to user inputs and room conditions. Refer to this section when you need specific information. This section includes details on control. Temperature Control 4.1.1 Cooling/Heating Required, in Percent (%) The temperature control program for the advanced microprocessor is based on a calculated % require- ment for cooling/ heating.
Dual Cooling Source If dual cooling is available, the sensible cooling system operates in the same manner as a GLYCOOL system, except that it is assumed that 100% chilled water capacity is available any time the chilled water temperature is 3°F below the return air temperature. The control will not permit compressor operation if the chilled water temperature is below the minimum chilled water temperature selected through the SETUP OPERATION menu.
Control Types 4.3.1 Proportional Control This is a standard control method that maintains the room at a temperature proportional to the load. The temperature maintained increases as the room load increases. At full load the room would be con- trolled at a temperature equal to the temperature setpoint plus the temperature sensitivity. If propor- tional control is selected, the gain is factory set and cannot be adjusted by the user.
Input #3 (+) Input #3 (–) Input #4 (+) Input #4 (–) Consult your Liebert supplier for a field installation kit to add these connections after unit delivery, if required. Table 15 Additional connections available after unit delivery Input #1...
This strip is provided on units ordered with analog inputs. (If this strip is not installed, there is a field installation kit available from your Liebert representative.) The 4-20 mA output of the LT750 must be connected to the first analog input, as shown.
Ground Current Detector (GCD) This device has been approved for use in Liebert 28, 34 and 40 kW Himod units. It is intended to mon- itor only the reheat circuit. It is not for whole equipment ground current protection, other components or personal ground fault protection.
When a new alarm occurs, it is displayed on the screen and the audible alarm is activated. If commu- nicating with a Liebert Site Product, the alarm is also transmitted. The display will also show a mes- sage to “PRESS ENTER KEY TO SILENCE” the alarm. After the alarm is silenced, the display will return to the Normal Status Display.
5.1.3 Custom Alarms Custom alarm messages are programmed at the LCD display. The alarms may be specified by the customer at the time of order. Additional devices and wiring may be required at the factory or by oth- ers. The message displayed may be included in this alphabetical list of alarms, or it may be custom- ized text (for up to 2 alarms).
If the unit has lost power, or the disconnect switch was turned off before the unit ON switch was pressed (to turn the unit Off), this local alarm will occur when power is restored to the unit. A Liebert remote monitoring unit (optional) will immediately indicate loss of power.
An optional flow switch is required for this alarm. Check for service valves closed, pumps not working, etc. 5.2.2 Smoke Detected Smoke is detected in the return air by an optional Liebert Smoke Detector. Check for source of smoke or fire, and follow appropriate emergency procedures. 5.2.3 Standby GC Pump On The primary pump has failed, and the standby pump is activated (glycol cooled and GLYCOOL units only).
OMPONENT PERATION AND AINTENANCE System Testing 6.1.1 Environmental Control Functions The performance of all control circuits can be tested by actuating each of the main functions. This is done by temporarily changing the setpoints. Cooling To test the cooling function, set the setpoint for a temperature of 10°F (5°C) below room temperature. A call for cooling should be seen and the equipment should begin to cool.
NEC Class 2, 24 volt wiring. Run wires to the terminal strip on the wire raceway in the com- pressor compartment and connect them to terminals 24 and 50-56. Figure 7 Recommended liquid sensor locations Liebert unit Recommended Liquitect...
Turn the power off before replacing filters. Himod filters are 20" by 20" by 4" thick. The filter is replaced from the front of the unit. First remove the t-strip gaskets. Starting with the filters on the right side, slide the filter up and outward toward you to remove it.
360 (2482) 6.4.3 Superheat Himod units are designed for high sensible heat ratios. At design conditions, suction superheat values in the range of 20-35°F (11-19°C) can be expected. Superheat can be adjusted by the Thermostatic Expansion Value (TEV). To determine superheat: 1.
6.4.5 Hot Gas Bypass Valve Operation The hot gas bypass is inserted between the compressor discharge line and the leaving side of the expansion valve through the side outlet distributor. The system, with normal operation when the evaporator is under full load, will maintain enough pressure on the leaving side of the hot gas valve to keep the valve port closed.
6.4.6 Air Cooled Condenser Restricted airflow through the condenser coil will reduce the operating efficiency of the unit and can result in high compressor head pressure and loss of cooling. Clean the condenser coil of all debris that will inhibit air flow. This can be done with compressed air or commercial coil cleaner.
6.4.7 Glycol Cooled Condensers Brazed Plate Condenser Each glycol cooled unit has a brazed plate condenser. Brazed plate condensers do not normally require maintenance or replacement if the fluid supply is clean. See Section 4.4 in the Installation Manual for further recommendations. If your system oper- ates at high head pressure with reduced capacity, and all other causes have been eliminated, the con- denser may be obstructed and needs to be replaced.
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Valve Disassembly 1. Shut off the water supply by using isolating valves. 2. Relieve the tension on the main spring by turning the adjusting screw (or collar) as far as it will go (provide a container to catch water below the valve). 3.
6.4.8 Compressor Functional Check The following diagnostic procedure should be used to evaluate whether the compressor is working properly. 1. Proper voltage to the unit should be verified. 2. The normal checks of motor winding continuity and short to ground should be made to determine if the inherent overload motor protector has opened or if an internal motor short or ground fault has developed.
6.4.9 Compressor Replacement Infrequently a fault in the motor insulation may result in a motor burn, but in a properly installed system burnouts rarely occur. Of those that do, most are the effects of mechanical or lubrication fail- ures, resulting in the burnout as a secondary consequence. If problems that can cause compressor failures are detected and corrected early, a large percentage can be prevented.
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Compressor Replacement Procedure Replacement compressors are available from your Liebert supplier. They will be shipped in a reusable crate to the job site as required by the service contractor. Upon shipping a replacement compressor, the service contractor will be billed in full for the compres- sor until the failed compressor has been returned to the factory.
Steam Generating Humidifier 6.5.1 Principle of Operation When the humidistat calls, the cylinder fills to 100% of the Full Load Amperage (FLA) or to the top of the cylinder, whichever comes first. See Figure 9. If it reaches 100% FLA, the water heats and boils away to a level giving 85% FLA. Figure 9 Operation schematic CONDENSATE RETURN (OPTIONAL)
6.5.2 Water Supply and Plumbing 1. The orifice in the fill valve is sized for an extended water pressure range of 15 to 150 psi. 2. With extremely dirty or muddy water sources, e.g., some well sources, ensure proper filtration by adding an external filter to the water line entering the unit.
Capacity Adjustment The Himod humidifier comes with an adjustable capacity PC board. This board has an adjustment pot for 25 to 100%. Component Operation and Maintenance...
Failure to replace the cylinder at the end of cylinder life may result in unit damage. Liebert is not responsible for any damages resulting from, or attributable to, the failure to replace a used cylinder (see manufacturer’s warranty).
Installing the New Cylinder 1. The reverse procedure should be followed to install a new cylinder. The main disconnect is to be left open until the cylinder is completely installed and reconnected. 2. The white sensor plug on all units is for the sensor pin, which always goes on the single pin offset from the others.
ROUBLESHOOTING Use this section to assist in troubleshooting your unit. Also refer to 5.0 - Alarm Descriptions. Sug- gestions are grouped by product function for convenience. WARNING Only qualified personnel should perform service on these units. Lethal voltage is present in some circuits.
6.5.3 - Start-Up and Operation. For a more detailed understanding, please contact your Liebert representative. 3. When contacting your local representative or Liebert for troubleshooting assistance, please ensure the serial number has been obtained for reference purposes. 4. Whenever the troubleshooting steps indicate a problem with the main PCB, first check all connections at the main control board.
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Fill Rate Fill rates of suspect units should be checked. Fill rates should measure nominally at 1" to 1-1/2" of vertical rise in water level in the cylinder in one minute. Clogged fill valve will cause lower fill rate. The fill valve strainer is removable and can be cleaned. Drain Time Manual drain time of a half full cylinder takes approximately 43 seconds.
Other Parts/Systems - Troubleshooting Table 19 Blower troubleshooting Symptom Possible Cause Check or Remedy No main power Check L1, L2 and L3 for rated voltage. Blown fuse or tripped circuit Check fuses or CBs to main fan. breaker (CB) Push reset button on main fan overload. Check Overloads tripped amp.
Table 21 Compressor and refrigeration system troubleshooting (continued) Symptom Possible Cause Check or Remedy Dirty condenser or drycooler fins Clean coil. Condenser equipment not Check operation. operating High refrigerant charge Check refrigerant charge. High discharge pressure Hot gas bypass valve adjusted Adjust properly.
Table 21 Compressor and refrigeration system troubleshooting (continued) Symptom Possible Cause Check or Remedy Faulty low pressure switch Repair or replace. Dirt or restriction in tubing to Check and clean tubing. pressure stat Compressor continually cycles Defective liquid line solenoid Check valve and solenoid operator;...
Table 24 Reheat troubleshooting Symptom Possible Cause Check or Remedy Control not calling for heat Check monitor status. Reheat will not operate; Jumper between terminals P34-1 and P34-2. If contactor not pulling in One of reheat safety stats open reheat operates, a safety is open. Remove jumper. Find open safety.
NNUAL AINTENANCE NSPECTION HECKLIST Date:_______________________________________ Prepared by:_________________________________ Model #:_____________________________________ Serial #:____________________________________ Filters Steam Generating Humidifier ___ 1. Restricted air flow ___ 1. Check canister for deposits ___ 2. Check filter switch ___ 2. Check condition of steam hoses ___ 3. Wipe section clean ___ 3.
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All rights reserved throughout the world. Specifications subject to change Hong Kong without notice. 852 2572220 ® Liebert and the Liebert logo are registered trademarks of Liebert Corporation. All names referred to are trademarks Fax: 852 28029250 or registered trademarks of their respective owners.
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