Baltimore Aircoil Company ICE CHILLER TSU-M Series Manual

TSU-M ICECHILLER® Thermal Storage Unit
for internal melt
OPERATING AND MAINTENANCE INSTRUCTIONS
MTSU-Mv01EN

Recommended Maintenance and
Monitoring Programme
Baltimore Aircoil Company's ICE CHILLER®Thermal Storage Units and Thermal Storage Coils have been
developed for long, trouble-free service when installed, operated and maintained properly. To ensure optimal
performance and maximum equipment life for your ICE CHILLER®Thermal Storage Unit, it is important that a
regular inspection/maintenance program be developed and implemented. This manual is provided as a guide to unit
operation and establishing an effective maintenance program for external melt systems.
Included in the manual are start-up and shutdown procedures, maintenance procedures and a schedule of
maintenance items and their recommended frequency for the ICE CHILLER®Thermal Storage Unit and its related
components. An illustration of the Thermal Storage Unit, with its major components identified, is provided in "ICE
Chiller®" on page5. All inspections, maintenance and monitoring actions should be recorded in a cooling system
logbook.
As part of your maintenance record, it is advisable to have a copy of the unit's certified drawing available for
reference during inspection and maintenance. If you do not have a copy of this drawing, or need further information
about the unit, contact your local BAC Service provider. You can find name, e-mail and phone number on the
website www.BACService.eu.
Checks and adjusments Start-Up Monthly Quaterly Every 6 Months Annually Shutdown
Operating Level X X
System Charging X
Inspections and Monitoring Start-Up Monthly Quaterly Every 6 Months Annually Shutdown
General condition X X
ICE CHILLER®Tank X X
ICE CHILLER®Water (1)
- Quality
- Level
X
X X
X
Ice Thickness X X
Coil X X
ICE LOGIC™ Ice Quantity controller:
- condition of sensor
- conductivity of tank water
X
X
X
X
Refrigerant:
- Glycol quality X
Cleaning procedures Start-Up Monthly Quaterly Every 6 Months Annually Shutdown
Disinfection X X X
Notes
1. Water Treatment and auxiliary equipment integrated in the cooling system may require additions to the table
above. Contact suppliers for recommended actions and their required frequency.
2. Recommended service intervals are for typical installations. Different environmental conditions may dictate
more frequent servicing.
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3. When operating in ambient temperatures below freezing, the unit should be inspected more frequently.
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Table of Contents
OPERATING AND MAINTENANCE INSTRUCTIONS
1 Construction Details 5
ICE Chiller® 5
2 General Information 6
Operating Conditions 6
Connecting Pipework 6
Safety Precautions 7
Disposal Requirements 7
3 Operating Instructions 8
General Information 8
Start-Up and Commissioning Procedures 8
Daily Operating Guidelines 9
Seasonal Shutdown 10
ICE LOGIC® Ice Quantity Controller 10
4 Water Care 17
About Water Care 17
Passivation 18
Special Water Treatment Considerations 18
5 Cold Weather Operations 19
About Cold Weather Operation 19
Protection of Operating Control Assembly 19
Insulation of Piping 19
Protection Against Coil Freezing 19
Ice due to Sub-Freezing Ambients 20
6 Maintenance Procedure 21
General 21
Checks and Adjustments 21
Inspections and Corrective Actions 24
Cleaning Procedures 26
7 Comprehensive Maintenance 27
About Comprehensive Maintenance 27
Prolonged Outdoor Stay 27
8 Further Assistance & Information 28
Balticare 28
More Information 28
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1 Construction Details
1 Construction Details W W W . B A L T I M O R E A I R C O I L . E U
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CONSTRUCTION DETAILS
ICE Chiller®
INTERNAL MELT APPLICATION
1. Wall Panel
2. Coil Support Beams
3. Glycol Connections
4. Galvanised Steel Coil
5. Watertight covers
6. Primary Liner
7. Extruded Polystyrene Insulation
8. Secondary Liner/Vapor Barrier
9. Sight Tube
Not shown: Ice Inventory Sensor - Ice Logic™ Ice Quantity Controller – Air Pump
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GENERAL INFORMATION
Operating Conditions
BAC cooling equipment is designed for the operating conditions specified below, which must not be exceeded
during operation.
•Wind Load: For safe operation of unshielded equipment exposed to wind speeds above 120 km/h installed at a
height above 30 m from the ground, contact your local BAC-Balticare representative.
•Seismic Risk: For safe operation of equipment installed in moderate and high hazard area's contact your local
BAC-Balticare representative.
ICE THERMAL STORAGE UNIT
1. For units designed to work with secondary coolants:
- Fluid Compatibility: Fluids circulated through the coil(s) must be compatible with the coil construction
material. Standard coils are constructed of black steel.
- Coil design pressure: max. 10 bar
- Max. temperature of fluid: +50°C
- Min. temperature of fluid: -20°C
PURGE REQUIREMENTS
The installer of BAC equipment must ensure proper system purging of air prior to operation. Entrained air can
obstruct the proper flow of glycol solution, resulting in higher operating pressures than design and reduced thermal
storage capacity.
Connecting Pipework
All piping external to BAC cooling equipment must be supported separately.
All connections in the external pipework (installed by others) must be leak free and tested accordingly. All piping
external to BAC cooling equipment must be supported separately.
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2 General Information
2 General Information

Safety Precautions
All electrical, mechanical and rotating machinery constitute a potential hazard, particularly for those not familiar
with its design, construction and operation. Accordingly, adequate safeguards (including use of protective
enclosures where necessary) should be taken with this equipment both to safeguard the public (including minors)
from injury and to prevent damage to the equipment, its associated system and the premises.
If there is doubt about safe and proper rigging, installation, operation or maintenance procedures, contact the
equipment manufacturer or his representative for advice.
When working on operating equipment, be aware that some parts may have an elevated temperature. Any
operations on elevated level have to be executed with extra care to prevent accidents.
AUTHORIZED PERSONNEL
The operation, maintenance and repair of this equipment should be undertaken only by personnel authorized and
qualified to do so. All such personnel should be thoroughly familiar with the equipment, the associated systems
and controls and the procedures set forth in this and other relevant manuals. Proper care, procedures and tools
must be used in handling, lifting, installing, operating, maintaining and repairing this equipment to prevent personal
injury and/or property damage.
MECHANICAL SAFETY
Mechanical safety of the equipment is in accordance with the requirements of the EU machinery directive.
Depending upon site conditions it also may be necessary to install items such as bottom screens, ladders, safety
cages, stairways, access platforms, handrails and toe boards for the safety and convenience of the authorized
service and maintenance personnel.
At no time this equipment should be operated without all access cover panels and access doors in place.
For more information consult your local BAC Balticare representative.
LOCAL REGULATIONS
Installation and operation of cooling equipment may be subject of local regulations, such as establishment of risk
analysis. Ensure regulatory requirements are consistently met.
Disposal Requirements
Dismantling of the unit and treatment of refrigerants, oil and other parts must be done with respect to the
environment whilst protecting workers from potential risks related to exposure to harmful substances.
National and regional legislation for material disposal and protection of workers should be taken into account with
regard to:
• Appropriate handling of construction and maintenance materials when dismantling the unit. In particular when
dealing with materials that contain harmful substances, such as asbestos or carcinogenic substances.
• Appropriate disposal of the construction and maintenance materials and components such as steel, plastics,
refrigerants and waste water according to local and national requirements for waste management, recycling
and disposal.
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2 General Information
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OPERATING INSTRUCTIONS
General Information
To ensure dependable, trouble-free, efficient operation of the thermal storage units, each system is provided with
factory installed, pre-set operating control assemblies. During normal operation a solid layer of ice at the top of the
tank will not form. However, should such a layer form due to unforeseen and unwanted operational circumstances,
the low level alarm can be activated. In such case melt out the ice completely.
Start-Up and Commissioning Procedures
For internal melt applications (TSU-M), the ice quantity is measured by measuring the difference in water level in
the tank that occurs due to ice build-up. Ice has a lower density than water, and therefore the water level increase
will be proportioned to the ice quantity inside the tank. The Analogue Ice Thickness Transmitter is factory installed
on the tank and consists of two major components:
- Transmitter box, for power supply and passive analogue 4-20 mA output signal.
- Sensor, which consists of a specially designed movable rod, installed in a PVC tube.
The movable rod detects the water level by measuring the difference in conductivity between air and water. The
displacement of this rod determines the water level and thus the ice quantity. In case the sensor is exposed to
subfreezing temperatures (outside installation), the sensor and connected PVC piping must be heat traced.
TANK FILLING AND ICE LOGIC CALIBRATION
The sensor is factory mounted and wired to the transmitter box, which is located at the connection end of the tank.
A “zero level” adjustment (=calibration) is needed at start-up. To follow the procedure for the correct calibration,
please refer to chapter: “Ice Logic™ Ice Quantity Controller”.
Make sure there is no ice left in the tank. Fill the Ice Thermal storage unit according to following instructions:
1. Open the ball valve so that the water can enter the water leve sensor. The water level in the sight tube must be
below the 0% level.
2. Use a hose through the hatch opening to fill the tank to the top of the coil. Water level must remain below 0%
level indicated on the label.
Caution
DO NOT OVERFILL
3. Continue to fill the tank slowly with a minimum of water turbulence until the water level in the sight tube
corresponds with the zero water level indicated on the label.
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Caution
MAKE SURE NO MORE WATER IS ADDED TO THE TANK.
4. Move the sensor upwards until the water level (0% ice) falls between the minimum and maximum calibration
lines indicated on the sensor tube.
5. Connect transmitter box to power supply, green led “POWER ON” lights up and the sensor starts measuring. If
not, please refer to “Troubleshooting” in this Manual in "ICE LOGIC® Ice Quantity Controller" on the next page.
6. Wait until the LCD-display says “WAITING”
7. Push the red button inside the transmitter box to enter the main menu, indicated on the display. See also
“Programming Mode” in chapter “Operating Instructions – Ice Logic™ Ice Quantity Controller”.
8. Choose “ZERO LEVEL” to enter the calibration menu.
9. Choose “CALIBRATE” to start the calibration.
SYSTEM CHECKS
Before initiating the first ice build cycle, check the following points:
1. Verify the system has been charged with a glycol solution of the type and concentration specified.
2. Confirm all circulating pumps are rotating in the proper direction.
3. Confirm there is sufficient load to discharge the tanks.
4. If any of the units are equipped with a heated enclosure around the operating control and sight tube, check to
ensure the heater and thermostat are wired and operational.
Once the checks are completed, start the initial ice build cycle and monitor the system throughout the cycle,
recording glycol temperatures and noting the duration of the build. Confirm the operating controls function properly
to terminate the build cycle and that once the build cycle is completed, the chiller is shut down and locked out until
the cooling cycle is initiated.
On multiple unit installations, once the initial ice build cycle has been completed, check all the sight tubes to verify
the water levels in each tank are equal. If the inventories are significantly out of balance, the flow rates of the
glycol solution to each of the thermal storage units should be checked and balanced. Then, after the next ice build
cycle, check the sight tubes once again to ensure balance has been achieved
Daily Operating Guidelines
BUILD CYCLE
For the most energy-efficient operation of the system, the controls should be designed to operate the build cycle as
follows:
Once the ice build cycle has been initiated, the glycol chiller(s) should run at full capacity without cycling or
unloading until the storage device is fully charged (recharged). At that point, the chiller and the glycol circulating
pump should be turned off and not allowed to restart until the discharge (cooling) cycle is initiated. Additionally, a
build cycle should not be re-initiated until approximately 15% of the ice has been melted.
DISCHARGE (COOLING) CYCLE
ICE CHILLER®Thermal Storage Units can be discharged in a variety of ways depending upon the system
configuration and objectives of the system designer. Consult the project drawings and specifications for direction
on how the system is to operate during the discharge (cooling) cycle. When the operating strategy calls for
operation of the chiller at any time during the discharge cycle, the operating control(s) used to control the ice build
cycle must be bypassed/deactivated when operating in the discharge cycle.
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It is recommended to completely melt-out the ice during each cooling cycle by pumping the warm glycol solution
through the coils. If complete melt-out cannot be accomplished, try to melt out as much ice as possible.
Caution
UNMELTED ICE IS WASTED ENERGY.
Seasonal Shutdown
ICE CHILLER® Thermal Storage Units installed indoors in a heated space (or outdoors where subfreezing
temperatures do not occur) do not require special attention or preparation for a seasonal or winter shutdown.
However, if subfreezing conditions do occur, please refer to section "About Cold Weather Operation" on page19
ICE LOGIC® Ice Quantity Controller
START-UP ICE LOGIC™
Analogue Ice Thickness Transmitter
The Analogue Ice thickness Transmitter measures the increase in water level that occurs when ice is build in a
tank. At regular times a metal rod is lowered towards the water level using a step motor, while another common rod
is already in the water. Once the moving rod reaches the water, a short circuit between both rods is detected by the
controller (conductivity measurement).The controller counts the number of steps taken by the step motor and
converts this to a mm value, a percentage and a 4-20mA output signal. Beside the display there is a green led
indicating power supply and two red leds for low and high water alarm. The screens below show what happens
when the power supply is activated.
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Baltimore Aircoil
Analogue
Ice Thickness Transmitter
When the power supply 220
v is switched on, following
screens appear on the
display
Range: 117mm
Sample Time: 8
Software Version
Busy...
->This means 100% ice
corresponds with 117mm
water level increase
->This means the time
interval between two
measurements is 8 minutes
Range: 117mm
Sample Time: 8
Software Version
Initialising done
At this moment the controller
is ready and the first sample
cycle can start
Level: mm.........%
Low level:
High level:
Status: Measuring
The rod is now moving
downwards till it reaches the
water level
Level: 28mm..........24%
Low level: OK
High level: OK
Status: Homing...
The rod has reached the
water level and has
measured a 28mm high
water level (corresponding
with 24% of the max range of
117mm) and the rod is
moving upwards to its home
position
Level: 28mm..........24%
Low level: OK
High level: OK
Status: Waiting 8
The rod has reached its
home position and the
controller is now waiting for 8
minutes till the next sample
PROGRAMMING MODE
Remove the lower cover (which must be removed for wiring up the Analogue ice thickness Transmitter)
Transmitter with loose cover
Press the red programming button for approximately 2 seconds until you hear a beep.
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3 Operating Instructions
3 Operating Instructions

Red button under lower cover of Analogue Ice Thickness Transmitter
Following screens will scroll. Press the red programming button to make your selection
Sequence of programming screens
1. Choose <Exit> to leave programming mode. When exiting the programming mode the controller will reset and
initialize again like in start-up mode. It will also perform a first measuring cycle
2. Choose <Sample time> to adjust the time interval between two measurements
3. Choose <Zero Level> to calibrate the ice sensor and set the zero ice level.
Caution
MAKE SURE THERE IS NO ICE LEFT IN THE TANK BEFORE SETTING THE ZERO LEVEL
SAMPLE TIME
Main Menu
<Sample time>
Press red program bottom when this screen appears
on display
Sample Time
Menu Current: 8 <5>
-> the current programmed sample time is 8 minutes -
> this value will change from <5> to <20> followed by
<exit>. Select the value you want for the new sample
time by pressing the red program button. Wait for
<exit> to leave this screen without changes.
CALIBRATION
Make sure there is NO ICE LEFT in the tank before setting the zero level. Check visually inside of the tank and
check water level on sight glass.
The water temperature should not be higher as 10°C during calibration to limit the influence of water density
variation as function of temperature change.
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Location of sensor, Control box and Sight glass on unit
1. Ice Logic® Sensor
2. Analogue Ice Thickness Transmitter
3. Water level Tube
OPERATING INSTRUCTIONS
The transmitter system is designed to be connected to an automatic system (like BMS, PLC, ...), using an
analogue output signal (4-20 mA)
The output of the transmitter system is a passive current loop signal. This output signal is connected to terminals 9
and 10. Terminal 9 is the negative output; terminal 10 is the positive output. Alarm signals are generated whenever
the water level is too low or too high:
ALARM ICE QUANTITY OUTPUT SIGNAL TERMINALS
low level below 0% 3.5 mA 14 (15) / 16
high level above 100% 24 mA 11 (12) / 13
Alarm signals
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WIRING SPECIFICATION
Terminal Fuse Description
LN L-N220VAC / max 10VA supply
Max. cable section is 2.5 mm2
1,2,3,4,5,6,7,8 Sensor terminals (Wiring done by B.A.C.). Wiring details see below wiring diagram.
9, 10 4-20mA passive current loop output.
External voltage: max. 24VDC / %o, 12VDC
Max. loop resistance at 24VDC: 600 Ohm.
Max. cable section 1.5 mm2
9 = negative, 10 = Positive
11, 12, 13 High level alarm contacts.
380VAC/10A - 24VDC/10A
Max. cable section is 2.5 mm2
- 11,13 = normally closed (NC)
- 12,13 = normally open (NO)
14, 15, 16 Low level alarm contacts.
380VAC/10A – 24VDC/10A
Mac cable section is 2.5mm2
- 14, 16 = normally closed (NC)
- 15,16 = normally open (NO)
Wiring specification
OUTPUT SIGNAL GRAPHICS
Output Signal graphic
1. Output signal (mA)
2. % Ice
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WIRING DIAGRAM
Wiring Diagram for Sensor
TROUBLE SHOOTING
1. Green “POWER” LED doesn’t light up.
- Check power supply (220VAC) at terminals L,N. If there is no power, check cables for damage.
- If the “POWER” LED still doesn’t light up, the control box is defective and must be repaired.
2. Ice level not corresponding
- If the indicated ice level is not corresponding to the actual ice percentage. The calibration should be done.
This adjustment is described in this manual in chapter Operating Instructions – Ice Logic® Ice thickness
controller
3. Check sensor
- Check if all wires of sensor cable are properly connected to terminals 1,2,3,4,5,6,7 and 8.
- All terminal screws should be properly tightened.
- None of these wires should be earthed.
- Check sensor cable for damages.
- If the control box is OK and all terminal connections are properly made, the sensor must be replaced.
- Read type number on the sensor to order a new one. One should know the maximum water level difference,
indicated in the first line of the LCD screen when starting the Analogue Ice Level Controller or at the side of
the transmitter.
4. Other
- If no output signal is registered from the controller, please note that this is a passive 4-20mA loop. The
supply voltage of this loop (24VDC) must be supplied by others.
- If incorrect measurements occur, most likely the water level has changed or the calibration was not done
correctly or wiring was not done right. So check water level in tank or do new zero level setting.
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3 Operating Instructions
3 Operating Instructions

- To check if the sensor works, the upper part of the sensor can be disassembled by unscrewing the 3 lower
screws of the PVC tube. The lower part can stay positioned on the tank. You can simulate a measuring
cycle by entering the main menu (press red button for 2 seconds until you hear a beep) and then exit it
again, or by switching the power supply of and on again.
Ice Logic® Sensor
- The measuring rod should move while the display is showing 'measuring'. If this is not the case the motor
could be damaged or the wiring to the control box is incorrect. (wire loose)
- To check if the sensor works hold it above water (the long rod should be in the water till half length). Once
the moving rod touches the water it should stop immediately and return to its home position. If this does not
happen, the rods are probably polluted. Clean them and recheck.
- When the sensor is stored for a long time under humid condition without being in operation, the motor-rod
system might corrode which makes it impossible for the motor to rotate. In that case you will get the alarm
'motor not responding'. You can check this by opening the sensor and see if the rod moves or not. When the
motor is corroded the sensor will need to be replaced. You could of course get the same failure message is
the step motor is out of operation (broken) or if the wiring towards the motor is not correct.
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4 Water Care
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WATER CARE
About Water Care
In the near freezing temperatures of the ICE CHILLER®Thermal Storage Unit, scale and corrosion are naturally
minimized. Therefore, for the tank water side of the units, a water treatment program to prevent scale or corrosion
is not normally needed, unless the water is corrosive in nature. To control biological growth, a biocide may be
needed on a periodic basis to prevent the growth of corrosive bacteria. In general, BAC recommends the following
guidelines. (See Table below).
Recommended Tank Water Quality
pH 7.0 to 9.0 *
Hardness (as CaCO3) 90 to 500 mg/l
Alkalinity (as CaCO3) 500 mg/l max.
Total Dissolved Solids 1000 mg/l max.
Chlorides 125 mg/l max.
Sulfates 125 mg/l max.
Conductivity 100-700 µS/cm
Water Quality Guidelines
* Tank water pH of 8.2 or higher will require periodic passivation of the galvanized steel coils to prevent "white rust", the accumulation of white,
waxy, non-protective zinc corrosion products on galvanized steel surfaces.
Minimum conductivity of 100 µS/cm and maximum of 700 µS/cm (at 0°C) is important for proper operation
of the ICE LOGIC™ ice quantity controller.
Caution
DO NOT TREAT THE TANK WATER WITH CHEMICALS THAT ALTER THE FREEZE POINT OF
WATER
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Passivation
When new systems are first commissioned, special measures should be taken to ensure that galvanized steel
surfaces are properly passivated to provide maximum protection from corrosion. Passivation is the formation of a
protective, passive, oxide layer on galvanized steel surfaces.
To ensure that galvanized steel surfaces are passivated, for the first 6-8 weeks of operation, the pH of the tank
water should be maintained between 7.0 and 8.2 and calcium hardness maintained between 100 and 300 mg/l (as
CaCO3). The passivation is complete and effective when the new zinc surfaces turn dull grey in colour. If white
deposits form on galvanized steel surfaces after the pH is returned to normal, this is a sign of white rust, and
therefore, the passivation process should be repeated to insure proper passivation and maximum corrosion
resistance.
In case that your water quality does not allow the pH to remain below 8.2, then you should consult a water
treatment specialist for advice on pH reduction or special passivation agents to promote proper passivation.
Special Water Treatment Considerations
ICE TANK WATER
• Since ice tanks can be on and off during the course of the year, it is possible for microbiological growth to
develop. Therefore, the best practice hygiene recommendation is for a dosage of non-oxidizing biocide
once/year. If the unit is an external melt, the biocide should be added after the unit is brought down for cleaning
and during the refill process, to insure proper mixing
• Following passivation, if the tank water is corrosive in nature (low hardness, low pH or alkalinity), the addition
of a corrosion 'non-precipitating' corrosion inhibitor is recommended. Examples of 'non-precipitating' corrosion
inhibitors are nitrites, molybdates and silicate based blends. Care must be taken not to use corrosion inhibitors
that raise the conductivity > 700 µS/cm, or alter the freezing point of the water. Therefore, such decisions need
to be taken with the advice of a water treatment specialist. For example, if the ice water needs food grade
approval because it could contaminant food products, then the silica based treatment programme is normally
used, if it meets food grade regulations.
GLYCOL SIDE OF THE ICE COIL
• Only use "inhibited" glycol that contains pH buffers. Never use industrial grade ethylene glycol. The reason for
this recommendation is that over time, glycol degrades and produces "glycolic acid" as a result. These acids
reduce the pH of the circulating water, and this will cause corrosion of steel materials of construction.
• As an added protection, the glycol loop should be treated with a nitrite, molybdate or silicate-based corrosion
inhibitor to promote metal passivation, and provide additional alkalinity to raise the pH above 9.0. Always
consult a water treatment specialist for recommendations on which corrosion inhibitor is most effective for your
specific water quality
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5 Cold Weather Operations
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COLD WEATHER OPERATIONS
About Cold Weather Operation
BAC equipment can be operated in subfreezing ambient conditions provided the proper measures are taken:
1. Insulation of piping.
2. Protection against coil freezing.
3. Elimination of ice due to sub-freezing ambient.
Listed below are general guidelines which should be followed to minimize the possibility of freeze-up. As these
guidelines may not include all aspects of the anticipated operation scheme, system designer and operator must
thoroughly review the system, location of the equipment, controls and accessories to ensure reliable operation at
all times.
When tanks are installed outdoors and exposed to subfreezing conditions, a minimum heat load must be applied to
the TSU to avoid solid ice formation inside the tank and prevent damage.
Protection of Operating Control Assembly
When the thermal storage unit will be exposed to subfreezing ambient temperatures, the Operating Control
Assembly, the sight tube assembly and, if so equipped, the Ice Inventory Sensor must be protected.
The sight tube and optional inventory sensor must be heat traced and insulated. It is not necessary to drain the unit
during cold weather. Freezing of the water contained in the tank during the winter will not damage the coil or unit.
Insulation of Piping
Precautions must be taken to protect the associated piping from freezing conditions. Heat tracing and insulation
should be installed on all piping connected to the unit to prevent cracking.
Protection Against Coil Freezing
TSU Ice Thermal Storage coil(s) must be protected from damage by freezing of the fluid inside the coil(s) when in
operation. Freeze protection must be obtained by the use of ethylene or propylene glycol or other anti-freeze
solutions in appropriate concentrations.
TSU Ice Thermal Storage units typically use a 30% (by weight) solution of industrially inhibited ethylene glycol for
both corrosion and freeze protection. The systems lowest operating temperature should be at least 3°C to 4°C
above the anti-freeze solution freeze point. Uninhibited ethylene glycol and automotive antifreeze solutions are
NOT to be used in TSU Ice Thermal Storage coil(s).
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% Ethylene Freeze Protection
20% -10°C
30% -16°C
40% -25°C
50% -39°C
Freeze Protection of Ethylene Glycol Solutions
The concentration of the glycol solution in the system should be verified to ensure it adequately protects the coils
and system piping from freezing. Adjust the concentration if necessary.
Ice due to Sub-Freezing Ambients
ICE CHILLER®tanks that have been exposed to severe or sustained subfreezing ambient temperatures, should
be checked before initiating an ice build cycle. Ice created by subfreezing ambient temperatures which
accumulates at the top of the tank and around the walls must be melted out before initiating a build cycle. This ice
can prevent normal water displacement during the build cycle, possibly leading to physical damage to the coil and
tank walls.
Ice melt can be confirmed visually, but it is recommended the temperature of the water in the tank be raised to
4,4°C to ensure all ice is melted.
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