Accu EQ Series User manual

Copyright Thermal Care Inc. 2010
EQ Series
Portable Chillers
Installation, Operation and Maintenance Manual

Table of Contents
Foreword.............................................................................................................................................................................1
Installation ..........................................................................................................................................................................1
Receiving Inspection ................................................................................................................................................................1
Rigging, Handling, and Locating Equipment.............................................................................................................................1
Electrical Power........................................................................................................................................................................1
Table 1 - Voltage Utilization Range.......................................................................................................................................2
Water Cooled Condenser Lines................................................................................................................................................3
(Water Cooled Units Only) .......................................................................................................................................................3
Table 2 - Condenser Water Flow Requirements...................................................................................................................3
Air Cooled Chillers Condenser Air ............................................................................................................................................3
(Air Cooled Units Only).............................................................................................................................................................3
Chilled Water Lines ..................................................................................................................................................................3
Table 3 - EQ Series Chilled Water Flow Requirements .........................................................................................................3
Figure 1 - Recommended Overhead Piping ..........................................................................................................................4
Interconnecting Refrigerant Piping ..........................................................................................................................................4
Start-Up...............................................................................................................................................................................4
Table 4 - Recommended Glycol Solutions ............................................................................................................................5
Controller Operation ...........................................................................................................................................................7
Table 5 - Microprocessor Control Fault Logic .......................................................................................................................7
Power .......................................................................................................................................................................................8
Start..........................................................................................................................................................................................8
Stop ..........................................................................................................................................................................................8
Alarm Reset ..............................................................................................................................................................................8
Alarm Silence............................................................................................................................................................................8
Lower Set Point Temperature ..................................................................................................................................................8
Raise Set Point Temperature....................................................................................................................................................8
No Flow ....................................................................................................................................................................................8
High Refrigerant Pressure ........................................................................................................................................................9
Low Refrigerant Pressure .........................................................................................................................................................9
Freezestat.................................................................................................................................................................................9
Low Oil Pressure.......................................................................................................................................................................9
Over Set Point ..........................................................................................................................................................................9
Under Set Point ........................................................................................................................................................................9
Pump On...................................................................................................................................................................................9
Compressor On.........................................................................................................................................................................9
Partial Load ............................................................................................................................................................................10
Water Make-Up......................................................................................................................................................................10
Low Water Level.....................................................................................................................................................................10
High Water Temperature .......................................................................................................................................................10
Probe Fault .............................................................................................................................................................................10
Changing Temperature Display Scale.....................................................................................................................................10
Diagnostic Error Codes ...........................................................................................................................................................12
Table 6 - Diagnostic Error Codes.........................................................................................................................................12
Control Options .................................................................................................................................................................13
Return Water Temperature Display .......................................................................................................................................13
Remote On/Off Contacts........................................................................................................................................................13
Remote Alarm Contacts .........................................................................................................................................................13
Alarm Horn .............................................................................................................................................................................13
Remote Control Panel ............................................................................................................................................................13
SPI Communications...............................................................................................................................................................13
Table 7 - SPI Baud Rate Adjustment ...................................................................................................................................14
Chiller Operation ...............................................................................................................................................................14
Coolant Circuit........................................................................................................................................................................14
Refrigerant Circuit ..................................................................................................................................................................14

Chiller Construction ...........................................................................................................................................................15
Compressor ............................................................................................................................................................................15
Air Cooled Condenser.............................................................................................................................................................15
(Air Cooled Units Only)...........................................................................................................................................................15
Water Cooled Condenser .......................................................................................................................................................15
(Water Cooled Units Only) .....................................................................................................................................................15
Condenser Water Regulating Valve (Water Cooled Units Only) ............................................................................................16
Condenser Remote Air-Cooled...............................................................................................................................................16
Evaporator..............................................................................................................................................................................16
Thermostatic Expansion Valve (TXV)......................................................................................................................................16
Refrigerant Sight Glass ...........................................................................................................................................................16
Refrigerant Filter Drier ...........................................................................................................................................................16
Hot Gas Bypass Valve .............................................................................................................................................................16
Reservoir ................................................................................................................................................................................17
Coolant Pump.........................................................................................................................................................................17
Pressure Gauge ......................................................................................................................................................................17
Y-Strainer................................................................................................................................................................................17
High Refrigerant Pressure Switch...........................................................................................................................................17
Low Refrigerant Pressure Switch ...........................................................................................................................................17
Freezestat...............................................................................................................................................................................17
Coolant Pressure Switch.........................................................................................................................................................18
Automatic Water Make-Up (Optional)...................................................................................................................................18
Upgraded Pumps (Optional)...................................................................................................................................................18
Preventive Maintenance ...................................................................................................................................................18
Once a Week ..........................................................................................................................................................................18
Once a Month ........................................................................................................................................................................18
Every Three Months ...............................................................................................................................................................19
Preventive Maintenance Checklist.....................................................................................................................................20
Troubleshooting ................................................................................................................................................................21
Charts and Drawings..........................................................................................................................................................23
Table 8 - EQ Air Cooled Chiller Electrical Specifications .....................................................................................................23
Table 9 - EQ Water Cooled Chiller Electrical Specifications................................................................................................24
Figure 2 - 60 Hz Pump Curves (water) ................................................................................................................................25
Figure 3 - 50 Hz Pump Curves (water) ................................................................................................................................26
Warranty ...........................................................................................................................................................................27

1
Foreword
The intent of this manual is to serve as a guide for placing your portable chiller in service and operating and maintaining it
properly. This manual is supplemented as required to accommodate any special items that may have been provided for a
specific application. The written information contained in this manual, as well as various drawings, are intended to be
general in nature. The schematics included in this manual are typical only. Actual schematics are included in the electrical
enclosure of the chiller and should be referred to for troubleshooting and servicing of the unit. Additional copies of wiring
diagrams are available upon request. We strive to maintain an accurate record of all equipment during the course of its
useful life. While every effort is made to standardize the design features of these chillers, the various options may make it
necessary to rearrange some of the components; therefore, some of the general drawings in this manual may differ from
your specific unit.
Specific references to current applicable codes, ordinances, and other local laws pertaining to the use and operation of this
equipment are avoided due to their ever-changing nature. There is no substitute for common sense and good operating
practices when placing any mechanical equipment into operation. We encourage all personnel to familiarize themselves
with this manual's contents. Failure to do so may unnecessarily prolong equipment down time.
The chilling equipment uses chemical refrigerants for heat transfer purposes. This chemical is sealed and tested in a
pressurized system containing ASME coded vessels; however, refrigerant gas can be released if there is a system failure.
Refrigerant gas can cause toxic fumes if it is exposed to fire. These units must be placed in a well-ventilated area, especially
if open flames are present.
Failure to follow these instructions could result in a hazardous condition. Consult the unit serial tag for information about
the refrigerant type and charge amount. Customers are advised to immediately implement a refrigerant management
program including a survey of all equipment to document the type and quantity of refrigerant in each machine. All
refrigeration service technicians must be certified by an EPA approved organization. It is recommended that good piping
practices are followed and that the information in this manual is adhered to. We cannot be held responsible for liabilities
created by substandard piping methods and installation practices external to the chiller.
We trust your equipment will have a long and useful life. If you should have any questions, please contact our Customer
Service Department specifying the serial number and model number of the unit as indicated on the nameplate.
Installation
Receiving Inspection
Each unit is skid mounted and boxed or crated to protect it during shipping. If the chiller has a remote air-cooled
condenser, the chiller and the condenser will ship skid mounted and will contain a holding charge of nitrogen. Before
accepting delivery, check the box or crate for visible damage. If damage is evident, it should be properly documented on
the delivery receipt and the box or crate should be immediately removed to allow for detailed inspection of the unit. Check
for broken refrigerant lines, oil leaks, damaged controls, or any other major component torn loose from its mounting point.
Any sign of damage should be recorded and a claim filed immediately with the shipping company. In order to expedite
payment for damages it is important to record and document damage. An excellent way to do this is by taking pictures.
Our Customer Service Department will provide assistance with the preparation and filing of your claims, including arranging
for an estimate and quotation on repairs.
Rigging, Handling, and Locating Equipment
Proper rigging methods must be followed to prevent damage to components. Avoid impact loading caused by sudden
jerking when lifting or lowering the chiller. Use pads where abrasive surface contact is anticipated.
The unit is designed for indoor use. If it is necessary to store the chiller in an unheated area when not in use, be sure that
all water is drained or that an adequate amount of antifreeze is added to prevent freeze-up of the unit. A primary concern
when designing your unit was serviceability, therefore, the chiller should be located in an accessible area.
Electrical Power
All wiring must comply with local codes and the National Electric Code. Minimum circuit ampacities and other unit
electrical data are on the unit nameplate and are shown in the Electrical Specification section at the back of this manual. A

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specific electrical schematic is shipped with the unit. Measure each leg of the main power supply voltage at the main
power source. Voltage must be within the voltage utilization range given in Table 1.
Table 1 - Voltage Utilization Range
Rated Voltage
Utilization Range
230
208 to 254
460
414 to 506
575
516 to 633
If the measured voltage on any leg is not within the specified range, notify the supplier and correct before operating the
unit. Voltage imbalance for three-phase systems must not exceed two percent. Excessive voltage imbalance between the
phases of a three-phase system can cause motors to overheat and eventually fail. Voltage imbalance is determined using
the following calculations:
% Imbalance = (Vavg –Vx) x 100 / Vavg
Vavg = (V1+ V2+ V3) / 3
Vx= phase with greatest difference from Vavg
For example, if the three measured voltages were 442, 460, and 454 volts, the average would be:
(442 + 460 + 454) / 3 = 452
The percentage of imbalance is then:
(452 –442) x 100 / 452 = 2.2 %
This exceeds the maximum allowable of 2%.
A terminal block is provided for main power connection to the main power source. The main power source should be
connected to the terminal block through an appropriate disconnect switch. A separate lug for grounding the unit is also
provided in the main control panel. Electrical phase sequence must be checked at installation and prior to start-up for all
three-phase systems. Operation of the compressor with incorrect electrical phase sequencing will result in mechanical
damage to the compressors. The phasing must be checked with a phase sequence meter prior to applying power. The
proper sequence should read “ABC” on the meter. If the meter reads “CBA”, open the main power disconnect and switch
two line leads on the line power terminal blocks (or the unit mounted disconnect). All components requiring electric power
are wired in-phase at the factory. Do not interchange any load leads that are from the unit contactors or the motor
terminals.
WARNING: It is imperative that L1-L2-L3 are connected in the A-B-C phase sequence to prevent equipment damage due to reverse
rotation.
CAUTION: The unit requires the main power to remain connected during off-hours to energize the compressor’s crankcase heater if
equipped. Disconnect main power only when servicing the chiller. The crankcase heater should remain on when the compressor is off
to ensure liquid refrigerant does not accumulate in the compressor crankcase.
WARNING: The control panel and safeties are wired such that connecting the appropriate power source to the main terminal block
energizes the entire electric circuitry of the chiller. A control transformer has been factory wired to step down the incoming power to
the 115-volt control power. Electric power at the main disconnect should be shut off before opening access panels for repair or
maintenance. The unit must be properly grounded in compliance with local and national codes.

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Water Cooled Condenser Lines
(Water Cooled Units Only)
The performance of the condenser is dependent on maintaining the proper flow and temperature of water through the
heat exchanger. Insufficient water flow or high condenser water supply temperatures will result in the reduction of cooling
capacity of the chiller. Extreme conditions will eventually result in the chiller shutting down due to high refrigerant
pressure. Performance can be adversely affected if the condenser is allowed to plug up from contaminants in the
condenser water stream. In order to reduce maintenance costs and chiller downtime, a water treatment program is highly
recommended for the condenser cooling water. If any condenser does become plugged, contact our Customer Service
Department for assistance in the proper procedure for cleaning out the condenser.
The standard cooling capacity is based upon 85°F (29°C) condenser cooling water supply. Under normal operating
conditions there will be a 10°F (6°C) rise through the condenser resulting in 95°F (35°C) exiting water temperature from the
condenser. To ensure proper water flow through the condenser, the condenser water pump should be able to handle up to
25 PSI (172 kPa) pressure drop through the condenser. While the design pressure loss is much lower than 25 PSI (172 kPa),
we recommend the pumping system be sized for this loss to ensure there will be sufficient supply pressure to the
condensers. To prevent damage to the condenser or regulating valve, the condenser water pressure should not exceed 150
PSIG (1034 kPa). The condenser water regulating valve controls the condenser water flow. The chiller loading and
condenser water inlet temperature will determine the actual flow. Table 2 shows minimum condenser water flow
requirements for the different size chillers at different supply temperatures under fully loaded conditions.
Table 2 - Condenser Water Flow Requirements
EQ2W02
EQ2W03
GPM (L/min) @ or below 70°F (21°C)
2.2 (8.3)
3 (11.3)
GPM (L/min) @ 75°F (24°C)
3 (11.3)
3.8 (14.3)
GPM (L/min) @ 80°F (27°C)
4.2 (15.9)
5.4 (20.4)
GPM (L/min) @ 85°F (29°C)
6.4 (24.2)
8.2 (31)
GPM (L/min) @ 90°F (32°C)
Call factory
Call factory
The minimum flows are determined using the condenser water regulating valve setting of 210 PSI (1.45 Mpa) for a given
supply temperature. The supply temperature range is from 40°F (4.4°C) to 90°F (32°C). Supply temperatures beyond this
range are not recommended and may lead to improper chiller operation.
Air Cooled Chillers Condenser Air
(Air Cooled Units Only)
In order to accommodate the air-cooled condenser, the chiller must be located in a well-ventilated area. A minimum of
three feet of clearance is recommended at both the condenser air inlet and condenser air discharge. The air cooled chillers
were not designed to have the condenser air discharge ducted. Improper clearance or poor ventilation will reduce the
cooling capacity of the chiller and may cause high refrigerant pressure problems. The condenser air inlet temperature
should be maintained above 50°F (15°C) in order to avoid possible low refrigerant pressure safety trips during start-up.
Chilled Water Lines
All chilled water piping should be adequately insulated to prevent condensation. If water is allowed to condense on the
piping, the state change of the water from gas to liquid will result in a substantial heat load that becomes an additional
burden for the chiller. Standard portable chillers have been designed to provide 50°F (10°C) coolant to the process. Under
normal operating conditions there will be a 10°F (6°C) rise through the process resulting in 60°F (16°C) return coolant
temperature to the chiller.
Table 3 - EQ Series Chilled Water Flow Requirements
Model
Nominal Flow
GPM (L/min)
Pressure Drop
PSI (kPa)
EQ3A01
2.4 (9)
1 (6.89)
EQ2A02
4.8 (18.1)
3 (20.68)
EQ2A03
EQ2W02
EQ2W03
7.2 (27.2)
4.8 (18.1)
7.2 (27.2)
5 (34.47)
3 (20.68)
5 (34.47)
The importance of properly sized piping between the chiller and process cannot be overemphasized. See the ASHRAE
Handbook or other suitable design guide for proper pipe sizing. In general, run full size piping out to the process and then
reduce the pipe size to match the connections on the process equipment. One of the most common causes of

4
unsatisfactory chiller performance is poorly designed piping. Avoid unnecessarily long lengths of hoses or quick disconnect
fittings that offer high resistance to water flow. When manifolds are required for water distribution, they should be
installed as close to the use point as possible. Provide flow-balancing valves at each machine to assure adequate water
distribution in the entire system. Typically when piping is overhead with a total run length over 25 feet (8 M) there should
be a check valve in the supply line and an inverted P trap with a vacuum break valve installed as shown in Figure 1. The
height of the return line must not exceed 25 feet (8 M) when using an inverted P trap configuration. If a vertical rise
greater than 25 feet (8 M) is required, a solenoid valve must be installed in the return line at the chiller instead of inverted P
trap with vacuum break.
Figure 1 - Recommended Overhead Piping
Interconnecting Refrigerant Piping
(EQR Models Only) The chiller unit is shipped with a nitrogen holding charge and has a full charge of oil, excluding the
additional charge for field piping. Proper evacuation is required prior to charging with refrigerant. The chiller is for use only
with the air-cooled condenser provided with the unit. The following section covers the required piping between the chiller
and the provided air-cooled condenser.
Caps are located on the discharge and liquid lines. These line sizes do not necessarily reflect the actual line sizes required
for the piping between the chiller and the air-cooled condenser. The installing contractor need only provide the
interconnecting piping between the chiller and the air-cooled condenser.
Refrigerant piping size and piping design has a significant effect on system performance and reliability. For specific pipe
sizing and configuration, refer to the EQR Series Chiller Remote Air Cooled Condenser Installation Guidelines Manual. All
piping should conform to the applicable local and state codes. Use refrigerant grade copper tubing only and isolate the
refrigeration lines from building structures to prevent transfer of vibration. Do not use a saw to remove end caps. This
might allow copper chips to contaminate the system. Use a tube cutter or heat to remove the caps. When sweating copper
joints it is important to flow dry nitrogen through the system. This prevents scale formation. Do not use soft solders. For
copper-to-copper joints use a phos-copper solder with 6% to 8% silver content. Use a high silver content brazing rod for
copper-to-brass or copper-to-steel joints. Only use oxy-acetylene brazing.
Start-Up
Every unit is factory set to deliver chilled water in accordance with the standard operating specifications for that particular
chiller. Due to variables involved with different applications and different installations, minor adjustments may be required
during the initial start-up to ensure proper operation. The following start-up procedure should be followed in sequence. If
trouble is encountered during start-up, the fault can usually be traced to one of the control or safety devices. This outline
can be used as a checklist for the initial start-up and for subsequent start-ups if the chiller is taken out of service for a
prolonged period of time.

5
1. Assure the main power source is connected properly, that it matches the voltage shown on the nameplate of the unit,
and that it is within the voltage utilization range given in Table 1. Electrical phase sequence must be checked at
installation and prior to start-up for three-phase systems. Operation of the compressor with incorrect electrical phase
sequencing will result in mechanical damage to the compressors. The phasing must be checked with a phase sequence
meter prior to applying power. The proper sequence should read “ABC” on the meter. If the meter reads “CBA”, open
the main power disconnect and switch two line leads on the line power terminal blocks (or the unit mounted
disconnect). All components requiring electric power are wired in-phase at the factory. Do not interchange any load
leads that are from the unit contactors or the motor terminals. Once proper power connection and grounding have
been confirmed, turn the main power on.
WARNING: Disconnect main power while working inside electrical enclosure or cabinet. Electrical shock or sudden start of
mechanical components may result in severe injury or death.
WARNING: It is imperative that L1-L2-L3 are connected in the A-B-C phase sequence to prevent equipment damage due to
reverse rotation.
Note: If chiller is equipped with a compressor crankcase heater, the main power must be on for 24 hours prior to starting the compressor to allow the
crankcase heater to sufficiently vaporize any liquid refrigerant that may be present in the compressor.
2. Check to make sure that all process chilled water piping connections are secure. Open the cabinet and fill the chilled
water reservoir with the proper water or water/glycol solution. See Table 4 for recommended glycol solutions. 25%
glycol is recommended even if running at temperatures higher than 25°F to help protect the evaporator from potential
freezing. Use glycol with a corrosion inhibitor only. The external sight glass located at back of unit may also be used to
fill or drain tank.
Table 4 - Recommended Glycol Solutions
Chilled Water Temperature
Percent Glycol By Volume
50°F (10°C)
Not required
45°F (7.2°C)
5 %
40°F (4.4°C)
10 %
35°F (1.7°C)
15 %
30°F (-1.1°C)
20 %
25°F (-3.9°C)
25 %
20°F (-6.7°C)
30 %
15°F (-9.4°C)
35 %
10°F (-12.2°C)
35 %
5°F (-15°C)
40 %
0°F (-17.8°C)
40 %
3. (EQ2W02 and EQ2W03 only) Check the condenser water lines to make sure all connections are secure. Make sure
sufficient condenser water flow and pressure are available, the condenser water supply is turned on, and all shut-off
valves are opened.
4. (EQR Models Only) Check the refrigerant lines to make sure all connections are secure and that a proper evacuation of
the chiller, the field piping, and the remote condenser has occured.
5. Charge the chiller with refrigerant. For EQR chillers, please refer to the EQR Series Chiller Remote Air-Cooled Condenser
Installation Guidelines Manual to determine the required refrigerant charge. EQA and EQW chillers come factory
charged and should require no additional refrigerant.
6. (EQR Models Only) Check the remote condenser main power and control wiring to ensure all connections are secure.
7. Verify that any existing refrigerant valves are open. Most units as standard contain no refrigerant valves.
CAUTION: Do not operate the unit with the compressor or liquid line service valves “CLOSED”. Failure to have these “OPEN”
may cause serious compressor damage.

6
8. (EQ2 series only) Make sure the Freezestat is set appropriately for the operating conditions of the chiller. The
Freezestat is located inside the main electrical control panel. It should be set at 10°F (5°C) below the minimum chilled
water temperature setting that the chiller will be operating. Reference Table 4 to be sure the coolant solution has
sufficient freeze protection (glycol) to handle at least 10°F (2.8°C) below the Freezestat setting. All chillers are shipped
from the factory with the Freezestat set at 38°F (3°C). This is done to protect against a possible freeze-up if no glycol
has been added to the coolant. Once the proper glycol solution has been added, the Freezestat can be adjusted to the
appropriate setting.
Note: The manufacturer’s warranty does not cover the evaporator from freezing. It is vital that the Freezestat is set properly.
9. Turn on the control power by pressing the Power button located on front display panel. The panel displays should now
be illuminated.
10. Due to extreme ambient temperatures that the unit may be exposed to during shipment, the High Refrigerant Pressure
switch may have tripped. If this is the case, disconnect the main power and reset the High Refrigerant Pressure by
depressing the manual reset button located on the switch. Reconnect the main power and turn the control power on
by pressing the Power button.
WARNING: Under no circumstance should the High Refrigerant Pressure or the Low Compressor Pressure switch be deactivated.
Failure to heed this warning can cause serious compressor damage, severe personal injury or death.
11. Establish flow through the evaporator. Standard units are provided with an internal pump and a coolant bypass to help
protect pump from dead-heading and the evaporator from freezing. The EQ3A01 contains an automatic pressure
actuated bypass which requires no adjustment under normal operating conditions. On all other models, the bypass
must be throttled open to accommodate a “no flow to process” situation. The internal pump can be energized by
pressing the Start button. If the unit has been customized and does not have an internal pump, the external pump
should be energized to establish flow through the evaporator.
Note: The compressor will not start as long as the coolant pressure switch is open. A positive flow must be established through the evaporator before
the compressor can operate. Under certain conditions the pressure loss in process lines may not be great enough to allow the pressure switch to close.
A process throttling valve must be installed to regulate process pressure if this condition appears.
12. Set water flow through the evaporator as indicated in Table 3. A significant increase in flow beyond the recommended
rate may damage the evaporator and create excessive pressure drops that influence the overall efficiency of the
system.
13. Set the desired leaving water temperature on the control panel using the Up and Down buttons. The chiller should
now be controlling to the selected temperature. Please note that if there is insufficient load the compressor may cycle
on and off causing swings in temperature.
14. Regulation of the chiller temperature is based on leaving water temperature. Unless otherwise specified, it is factory
set to deliver coolant at 50°F (10°C). Adjust to the desired operating temperature. Resetting the temperature will
change the operating conditions of the chiller. Any lower readjustment of the controller must be done only after
referencing Table 4 to ensure that the coolant has adequate antifreeze protection.
15. Operate the system for approximately 30 minutes. Check the liquid line sight glass. The refrigerant flow past the sight
glass should be clear. Bubbles in the refrigerant indicate either low refrigerant charge or excessive pressure drop in the
liquid line. A shortage of refrigerant is indicated if operating pressures are low and subcooling is low. Normal
subcooling ranges are from 10°F (5.5°F) to 20°F (11°C). If subcooling is not within this range, check the superheat and
adjust if required. The superheat should be approximately 10°F (5.5°C). Since the unit is factory charged, adding or
removing refrigerant charge should not be necessary. If the operating pressures, sight glass, superheat, and subcooling
readings indicate a refrigerant shortage, gas-charge refrigerant as required. With the unit running, add refrigerant
vapor by connecting the charging line to the suction service valve and charging until operating conditions become
normal.
CAUTION: A clear sight glass alone does not mean that the system is properly charged. Also check system superheat,
subcooling, and unit operating pressures. If both suction and discharge pressures are low but subcooling is normal, a problem
other than refrigerant shortage exists. Do not add refrigerant, as this may result in overcharging the circuit.

7
Once proper flow and temperature are achieved, press the Stop button. The unit is now ready to be placed into service.
Controller Operation
The chiller includes a microprocessor controller designed to
perform all control functions directly from the front panel. When a
button is depressed, a click will be felt and the corresponding LED
will be energized. Only one button should be pressed at a time.
Table 5 shows the basic control fault logic for the microprocessor
controller.
Table 5 - Microprocessor Control Fault Logic
Fault
Alarm
Indication
Compressor
Shutdown
Pump
Shut Off
Alarm
Reset
Required1
Manual
Reset
Required2
Remote
Alarm
Activated3
No Flow
LED
Yes
Yes
No
No
Yes
High Refrigerant Pressure
LED
Yes
Yes
Yes
No
Yes
Low Refrigerant Pressure
LED
Yes
No
Yes
No
Yes
Freezestat
LED
Yes
No
Yes
Yes
Yes
Low Oil Pressure
LED
Yes
Yes
Yes
Yes
Yes
Over Set Point
LED
No
No
No
No
Yes
Under Set Point
LED
Yes
No
Yes
No
Yes
Low Water Level
LED
No
No
No
No
No
High Water Temperature
LED
No
No
No
No
No
Probe Fault
LED
Yes
Yes
Yes
No
Yes
Low Power
Pr OFF
Yes
Yes
Yes
No
Yes
Pump Overload
Err 126
Yes
Yes
Yes
Yes
Yes
Compressor Overload
Err 127
Yes
Yes
Yes
No
Yes
High Temperature Safety
Err 128
Yes
Yes
Yes
No
Yes
1 Alarm Reset button or Stop button on control panel must be pressed.
2 Safety control must be manually reset before the controller can be reset.
3 Activates the alarm horn (if included) and closes the alarm contact (if included).