SMC-050 to SMC-150 Series
0.5 to 1.5 hp Portable Chillers
Operation and Installation Manual
Sterling, Inc./Sterlco
P. O. Box 245018
5200 West Clinton Avenue
Milwaukee, WI 53224-9518
( )
Tel 414 354-0970
( )
Fax 414 354-6421
Part No. A0544325
Bulletin No. SC2-615.1
Safety Considerations
SMC Series Chillers are designed to provide safe and reliable operation when installed and
operated within design specifications, following national and local safety codes.
To avoid possible personnel injury or equipment damage when installing, operating or
maintaining this equipment, use good judgment and follow these safe practices:
; Follow all SAFETY CODES.
; Wear SAFETY GLASSES and WORK GLOVES.
; Use care when LOADING, UNLOADING, RIGGING, or MOVING this equipment.
; Operate this equipment within design specifications.
; OPEN, TAG, and LOCK ALL DISCONNECTS before working on equipment. It is a good
idea to remove the fuses and carry them with you.
; Make sure the chiller is properly GROUNDED before switching power on.
; When welding or brazing in or around this equipment, be sure VENTILATION is
ADEQUATE. PROTECT adjacent materials from flame or sparks by shielding with sheet
metal. An approved FIRE EXTINGUISHER should be close at hand and ready for use if
needed.
; The refrigeration system can develop refrigerant pressures in excess of 500 psi (3,450 kPa).
DO NOT CUT into the system without first relieving pressure.
; Do not jump or bypass any electrical safety control.
; Do not restore power until all tools, test equipment etc. have been removed and the panels
replaced.
; Only PROPERLY TRAINED personnel familiar with the information within this manual
should work on this equipment.
SMC Series Chillers
Page 3
Table of Contents
1 General Information................................................. 7
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
1-9
Introduction
Necessary Documents
Models Covered
Available Options
Uncrating Your New Chiller
In the Event of Shipping Damages
If the Shipment is Not Complete
If the Shipment is Incorrect
Returns
2 Chiller Installation.................................................. 13
2-1
2-2
2-3
2-4
2-5
Electrical Connections
Process Water Connections
SMC Condenser Air Supply
Water Reservoir
Overhead Process Considerations
3 Sequence of Operation.......................................... 17
3-1
3-2
3-3
3-4
3-5
Chilled Water Circuit
Refrigeration Circuit
High Pressure Cutout
Low Pressure Cutout
Remote Start/Stop Interlock
Page 4
SMC Series Chillers
Table of Contents
4 Startup Checklists.................................................. 23
4-1
4-2
4-3
Introduction
SMC Pre-Startup Checklist
SMC Startup Checklist
5 Microprocessor Control ........................................ 25
5-1
5-2
5-3
Introduction
Setting the Process Water Temperature
Setting the Alarm Value
6 Optional Graphic Panel ......................................... 27
6-1
6-2
Indicator Lights
Switches
7 Routine Maintenance............................................. 29
7-1
7-2
Lubrication
Condenser Maintenance
8 Troubleshooting Guide.......................................... 33
SMC Series Chillers
Page 5
Charts and Figures
1
2
3
4
5
6
7
8
SMC050A Process Pump Curves
10
10
11
12
15
16
19
20
21
22
24
26
28
29
30
31
35
SMC100A Process Pump Curves
SMC150A Process Pump Curves
SMC Series Chiller Specifications
Ethylene Glycol Curve
Overhead Piping
SMC Component Identification
Piping Schematic — 1 Pump with Reservoir
9
Piping Schematic — 1 Pump without Reservoir
10
11
12
13
14
15
16
17
Piping Schematic — No Pump, No Reservoir
SMC Water Circuit Pressure Drop Table
SMC Control
Optional Graphic Panel
Typical SMC Subpanel
Typical SMC Wiring Schematic
SMC Wiring Schematic for Chillers with No Pump or Reservoir
SMC Spare Parts List
Page 6
SMC Series Chillers
1
General Information
1-1 Introduction
SMC Series Water Chillers are reliable, accurate, and easy-to-use air cooled chillers designed for
use with water/glycol. Standard range of operation is 30°F (-1°C) to 65°F (18°C). A crankcase
pressure regulating valve option is available for processes requiring a leaving water temperature
of up to 75°F (24°C). SMC models are available in ½ hp (373 W), 1 hp (746 W), and 1½ hp
(1,118 W) models and have an internal six gallon (23 liter) reservoir. All models are self
contained, fully assembled, and shipped ready to use.
A properly installed, operated, and maintained SMC Series Chiller will provide many years of
reliable operation. To get the most satisfaction from your new chiller, read and follow the
instructions in this manual.
1-2 Necessary Documents
The following documents are necessary for the operation, installation and maintenance SMC
Series Chillers. Additional copies are available from Sterlco. Familiarize the appropriate
personnel with these documents:
; This manual.
; The electrical schematic and connection diagram mounted inside the control enclosure.
Typical schematics for general reference are provided in Figures 14 and 15 on Pages 32 and
33.
; The operation and installation manuals for installed accessories and options.
; The Customer Parts List included in the information packet.
1-3 Models Covered
This manual provides operation, installation, and maintenance instructions for SMC Series
Chillers. Model numbers are on the serial tag. Please know the model number, serial number and
operating voltage of your chiller if you need to contact Sterlco.
SMC Series Chiller models are designated by approximate compressor horsepower. A SMC050
chiller has a ½ hp (373 W) compressor, a SMC100 chiller has a 1 hp (746 W) compressor, and a
SMC150 chiller has a 1½ hp (1,118 W) compressor.
SMC Series Chillers
Page 7
1-4 Available Options
SMC Series Chillers are available with options that tailor the unit to your requirements. Some are
factory installed, some can be retrofitted in the field. Consult your local Sterlco Sales
Representative. Some of these options are:
Special Pumps
Special pump options are available for greater pressure and flow rates. Bronze and stainless steel
wetted surface standard flow pumps ranging from 30 psi (207 kPa) to 60 psi (414 kPa) are
available.
Reservoirs
SMC Series Chillers are available without a reservoir for processes that use their own reservoir.
Power Cord
A 10 foot (3 meter) power cord is available to speed SMC installation.
Casters
Four 2-inch (5 cm) swivel casters add mobility to the SMC unit.
CPR Valve
A crankcase pressure regulating (CPR) valve is available for leaving water temperatures up to
75°F (24°C).
1-5 Uncrating Your New Chiller
SMC Series Chillers are shipped mounted on a skid, enclosed in a plastic wrapper, and open
crated on all four sides and top.
; Pry the crating away from the skid and remove. Use a pry bar to remove the blocks securing
the unit to the skid.
; Lift the unit off the skid with a fork truck. Insert forks between skid and chiller from the side
until they protrude beyond the opposite side of the unit. The forks must be equidistant from
the center line of the unit and the unit must be balanced on the forks.
; Lift slowly and only high enough to clear the skid. Use a pry bar if necessary to remove the
skid from the unit.
; Lower slowly. The unit will land on its feet or casters and can be moved into position.
Page 8
SMC Series Chillers
1-6 In the Event of Shipping Damages
Important!
According to the contract terms and conditions of the Carrier,
the responsibility of the Shipper ends at the time and place of shipment.
The Carrier then assumes full responsibility of the shipment.
; Notify the transportation company’s local agent.
; Hold the damaged goods and packing material for the examining agent’s inspection. Do not
return any goods to Sterlco before the transportation company inspection and authorization.
; File a claim against the transportation company. Substantiate the claim by referring to the
agent’s report. A certified copy of our invoice is available upon request. The original Bill of
Lading is attached to our original invoice. If the shipment was prepaid, write us for a
receipted transportation bill.
; Advise Sterlco regarding your wish for replacement.
1-7 If the Shipment is Not Complete
Check the packing list. The apparent shortage may be intentional. Back-ordered items are noted
on the packing list. You should have:
; SMC Series Chiller
; Bill of Lading
; Packing List
; Operating and Installation Packet
Re-inspect the container and packing material to see if smaller items have been missed during
unpacking. Determine that the item was not taken from the area before the shipment was checked
in. Notify Sterlco immediately of the shortage.
1-8 If the Shipment is Incorrect
; If the shipment is not what you ordered, contact Sterlco immediately. Include the order
number and item.
; Hold the items until shipping instructions are received.
SMC Series Chillers
Page 9
1-9 Returns
Important!
Do not return any damaged or incorrect items until
you receive shipping instructions from STERLCO.
Figure 1
SMC050A Process Pump Curves
SMC050A - PROCESS PUMPS SELECTIONS
60 HERTZ PUMP CURVE
TOTAL HEAD
MTRS PSI FEET
49 69 160
37 52 120
24 35 80
12 18 40
BZ050C
BZ050A
BZ050B
U. S. GALLONS
PER MINUTE
LITRES
0.4
1.5
0.8
3.0
1.2
4.5
1.6
6.1
2.0
7.6
2.4
9.1
2.8
3.2
3.6
4.0
4.4
4.8
10.6
12.1
13.6
15.1
16.7
18.2
PER MINUTE
CURVES REPRESENT PUMP DISCHARGE ADJUSTED FOR INTERNAL BY-PASS
Do not extrapolate pump curves.
Figure 2
SMC100A Process Pump Curves
SMC100A- PROCESS PUMPS SELECTIONS
60 HERTZ PUMP CURVE
TOTAL HEAD
PSI
MTRS
FEET
49 69 160
37 52 120
24 35 80
12 18 40
BZ100C
BZ100B
BZ100A
U. S. GALLONS
PER MINUTE
LITRES
1.6
2.0
7.6
2.4
9.1
2.8
3.2
3.6
4.0
4.4
4.8
5.2
5.6
6.0
6.4
6.1
10.6
12.1
13.6
15.1
16.7
18.2
19.7
21.2
22.8
24.2
PER MINUTE
CURVES REPRESENT PUMP DISCHARGE ADJUSTED FOR INTERNAL BY-PASS
Do not extrapolate pump curves.
Page 10
SMC Series Chillers
Figure 3
SMC150A Process Pump Curves
SMC150A - PROCESS PUMPS SELECTIONS
60 HERTZ PUMP CURVE
TOTAL HEAD
MTRS PSI FEET
49 69 160
37 52 120
24 35 80
12 18 40
BZ150B
BZ150C
BZ150A
U. S. GALLONS
PER MINUTE
LITRES
2.0
2.4
9.1
2.8
3.2
12.1
3.6
4.0
4.4
16.7
4.8
5.2
5.6
6.0
6.4
6.8
7.6
10.6
13.6
15.1
18.2
19.7
21.2
22.7
24.3
25.8
PER MINUTE
CURVES REPRESENT PUMP DISCHARGE ADJUSTED FOR INTERNAL BY-PASS
Do not extrapolate pump curves.
SMC Series Chillers
Page 11
Figure 4
SMC Series Chiller Specifications
Optional gauge package
Optional gauge package
Power cable entrance,
either side
Side cover
handle
Sight glass
Drain plug
PUMP
PRESSURE
(3/4" NPT)
Mini Chiller
PC Series
Portable Chiller
ON
LOW
HIGH
PUMP
ON
COMPRESSOR
ON
REFRIGERANT
PRESSURE
REFRIGERANT
PRESSURE
POWER
To Process
(3/4" NPT)
No Flow indicator
(for pumpless
units only)
OFF
A0537868
NO FLOW
34"
18 7/16"
From Process
(3/4" NPT)
13 7/16"
Rear View
Optional Casters
26"
Right Side View
20"
Front View
Capacity
@ 65°F
LWT 75°F LWT 90°F
Capacity
@ 50°F
Nominal
Chilled
Water
Amp
Draw
Process
Dimensions
(inches)
Operating Shipping
Model
Ambient
Ambient
Compressor
Pump
Connection 230/1/60
Weight
Weight
Number
(Btuh)
(Btuh)
(gpm)
(hp)
(inches NPT) Running
L
W
H
(lbs)
(lbs)
1/3 hp,
1.2 gpm @
24 psig
1/3 hp,
2.4 gpm @
34 psig
1/3 hp,
3.6 gpm @
24 psig
SMC-050
8,100
4,800
9,550
1.2
2.4
3.6
8A
20 26 34
20 26 34
20 26 34
265
325
345
265
325
345
½
¾
SMC-100 14,000
SMC-150 25,400
10A
1
¾
1½
16,000
12A
¾
Capacity
@ 18°C
Capacity
@ 10°C
Nominal
Amp
LWT, 24°C LWT, 32°C Chilled
Process
Connection 230/1/60
(inches NPT) Running
Draw
Dimensions
(cm)
Operating Shipping
Model
Number
Ambient
Ambient
Water
Compressor
(watts)
Pump
Weight
Weight
(watts)
(watts)
(lpm)
L
W
H
(kg)
(kg)
224 watts,
4.5 lpm
@ 207 kPa
SMC-050
SMC-100
SMC-150
2,374
4,103
7,444
1,407
2,800
4,690
4.5
9.0
373
746
8A
51 66 86
51 66 86
51 66 86
120
147
156
120
147
156
¾
224 watts,
9.0 lpm
@ 234 kPa
10A
¾
224 watts,
13.6 lpm
@ 207 kPa
13.6
1,118
12A
¾
Page 12
SMC Series Chillers
2
Chiller Installation
2-1 Electrical Connections
Check serial tag voltage and amperage requirements and make sure your electrical service
conforms. See Figure 4 on Page 12 for total running amps.
Bring properly sized power leads and ground from a fused disconnect (installed by your
electrician) to the main power terminal in the chiller’s electrical enclosure.
; Electrical connections must comply with all applicable electrical codes.
; The chiller must be grounded in accordance with NEC Article 250.
; Voltage must be within 10% of the chiller’s nameplate rating.
2-2 Process Water Connections
; All external chilled water connections to the process must be of adequate size.
; See Figure 6 on Page 18 for sizing recommendations.
; The largest possible openings and passages should be provided for the flow of chilled water
through platens, dies, molds or other pieces of equipment.
Important!
Keep any pressure drop in external process piping
to an absolute minimum for optimum unit operation.
To Process
Connect the TO PROCESS chilled water supply outlet to the process being cooled.
From Process
Connect the FROM PROCESS chilled water return inlet to the return from the process back into
the chiller for cooling and recirculation.
; Sterlco recommends a strainer on the FROM PROCESS return line.
SMC Series Chillers
Page 13
Process Water Bypass
All SMC chillers have an internal bypass device (patent pending). If the process flow becomes
blocked during chiller operation, this component allows water to flow through the chiller. This
protects the chiller from freeze-up, excessive pressures, and pump damage, and allows other
safety features to remain effective.
2-3 SMC Condenser Air Supply
SMC chillers use the surrounding air to cool the condenser.
; Condenser air entering the SMC unit should be at least 65°F (18°C). Operation with air
below 65°F (18°C) can cause the low pressure cutout to shut down the chiller due to the low
refrigerant pressure.
; Install the chiller in an area where there is free passage of air for condensing.
; Provide 18” (46 cm) or more clearance for the chiller’s air intake.
; Make provisions to exhaust the heated air discharged from the chiller.
; Do not put the SMC unit where steam, hot air or fume exhausts will be drawn into the
condenser.
; Air-cooled condensers must be cleaned frequently. Neglect reduces capacity, increases
operating costs, and leads to possible chiller failure. See Chapter 7 on Page 31 for cleaning
instructions.
; Normal condensing pressure with 95°F (35°C) air is approximately 180 psi (1,241 kPa) for
the SMC050A and SMC100A; 275 psi (1,897 kPa) for the SMC150A.
SMC Ambient Temperature Ranges
Ambient temperature range
Operation
Minimum temperature
65°F (18°C)
Maximum temperature
100°F (38°C)
Storage
40°F (4°C)
120°F (49°C)
2-4 Water Reservoir
During startup and when additional solution is required, see Figure 5 on Page 17 for the
recommended ethylene glycol/water solution. This chart shows the proportions needed to
provide freeze protection to 20°F/°C below the desired process setpoint.
; Add a pre-mixed solution to provide freeze protection to a temperature 20°F/°C below the
normal operating temperature of the chiller.
; Use industrial quality (not automotive) ethylene glycol.
Page 14
SMC Series Chillers
; A corrosion inhibitor suitable for the materials in the system should be added to the
glycol/water solution.
; If straight water use is desired, contact the Sterlco Engineering Department.
; The six gallon (23 liter) reservoir is not designed to withstand water pressure above 5 psi (34
kPa).
; The fill opening and vent line must be vented to the atmosphere for proper operation.
Figure 5
Ethylene Glycol Curve
Ethylene glycol required
for evaporator freeze protection
30%
20%
Ethylene
glycol
percent
by
volume
10%
0%
0º
30º
40º
50º
60º
70º
Chilled water
operating temperature °F
(set point)
Normal operating range is between 30°F and 70°F
SMC Series Chillers
Page 15
2-5 Overhead Process Considerations
If your application has chilled water or process piping above the reservoir fill and vent level,
install a standpipe to a point 1’ (30 cm) above the highest point in the system.
In applications where the process or its piping is 15 feet (4.6 m) or more above the reservoir, you
must take steps to prevent over-pressurization of the reservoir. This condition can occur on
system shutdown when the water in the system drains into the reservoir.
To prevent this, install a check valve in the unit TO PROCESS line and a vacuum breaker at the
high point of the return FROM PROCESS line. See Figure 6 on Page 18 for more information.
Note: The reserve capacity of the reservoir can hold a volume equal to 20 feet (6.1 m) of 1-inch
(2.5 cm) pipe.
Figure 6
Overhead Piping
Vent
The reservoir vent & fill line
to be piped 12" above the highest
point of the system. The vent line
Vacuum Breaker
Assembly
Cap
must remain open to the atmosphere.
12"
Check
Valve
1/8"
Hole
1/4"
6" Min.
Process Return
Process Supply
Strainer
Add check valve
if system piping
extends 15 feet
above reservoir.
Indicates end of STERLCO piping
Page 16
SMC Series Chillers
3
Sequence of Operation
Important!
• The SMC unit has a leaving water temperature range of 30°F (-1°C) to 65°F
(18°C). Do not attempt to run the SMC unit outside this temperature range or
damage to the unit may occur.
• When operating the SMC unit between 30°F (-1°C) and 40°F (5°C), you must
use a solution of 75% water and 25% industrial-grade ethylene glycol with a
suitable corrosion inhibitor to protect the SMC unit from freeze-up. See
Figure 5 on Page 17 for more information. Such damage is not covered by
the Sterlco warranty.
3-1 Chilled Water Circuit
Figures 8, 9, and 10
; Process cooling water supply and return connections are made at the pipe stubs at the rear of
the chiller.
; Warm water returns from the process and enters the reservoir tank.
; The process water is pumped through the evaporator where it is cooled.
; The coolant flows to the process and returns to repeat the cycle.
; A chilled water bypass assembly (patent pending) between the supply and return lines
guarantees a constant flow through the evaporator during intermittent low or no-flow
conditions.
; A flow switch in units without pumps will prevent the compressor from running without
adequate flow through the evaporator
3-2 Refrigeration Circuit
„ Liquid refrigerant from the condenser passes through a filter/dryer which removes moisture
and other contaminants.
„ The refrigerant then passes through the thermal expansion valve which allows the
refrigerant to expand and cool the inside of the heat exchanger. The refrigerant flows
through the suction line to the compressor.
„ The refrigerant gives up its heat as it re-condenses to a liquid in the condenser and the cycle
starts over again.
SMC Series Chillers
Page 17
3-3 High Pressure Cutout
The high pressure cutout is an electro-mechanical safety feature that opens the control circuit if
the system condensing pressure exceeds a safe level. The chiller will automatically restart when
the pressure drops back to an acceptable level.
Model
Cuts out if condensing pressure exceeds:
275 psi (1,897 kPa)
SMC050A
SMC100A
SMC150A
275 psi (1,897 kPa)
400 psi (2,759 kPa)
Important!
Call a refrigeration service technician to analyze
the problem if high pressure recurs.
3-4 Low Pressure Cutout
The low pressure cutout is an electro-mechanical safety feature that prevents compressor suction
pressure from dropping below a preset point.
It is factory set to open the control circuit when pressure drops below a safe level. The chiller
will automatically restart when the suction pressure reaches an acceptable level.
Model
SMC050
A
Cuts out if suction pressure falls below:
15 psi (103 kPa)
SMC100
A
SMC150
A
15 psi (103 kPa)
35 psi (241 kPa)
3-5 Remote Start/Stop Interlock
A contact is provided to allow interlocking of the SMC Series Chiller with process controls. To
use this feature, remove the jumper between Terminals X1 and 1 on Terminal Block 1. Supply a
switch or dry contact interlock connected in series between these two terminals. See Figures 14
and 15 on Pages 32 and 33 for more information.
Page 18
SMC Series Chillers
Figure 7
SMC Component Identification
SMC Series Chillers
Page 19
Figure 8
Piping Schematic — 1 Pump with Reservoir
Air-cooled condenser
Discharge line
Liquid line
Refrigeration
evacuation valve
Relief
valve
Refrigeration
evacuation valve
Filter
Filter
Suction
Line
Drier
Expansion Sight
valve
glass
Evaporator
Legend
Refrigeration lines
Equalizing line
Power element
Chilled water piping
Condenser water piping
Refrigeration
access valve
End of unit piping
Optional
pressure
gauge
Temperature
probe
TC
High
pressure
control
S
P
To
Process
Low
pressure
control
Bypass
Optional
CPR valve
Refrigeration
access valve,
compressor-mounted
Compressor
Vent
Fill
Sight
glass
Tank
Drain
Pump
From
Process
Page 20
SMC Series Chillers
Figure 9
Piping Schematic — 1 Pump without Reservoir
Air-cooled condenser
Discharge line
Liquid line
Refrigeration
evacuation valve
Relief
valve
Refrigeration
evacuation valve
Filter
Filter
Suction
drier
Legend
line
Refrigeration lines
Chilled water piping
Condenser water piping
End of unit piping
Expansion
valve
Sight
glass
Evaporator
Equalizing line
Power element
Refrigeration
access valve
Optional
pressure
gauge
Temperature
probe
TC
High
pressure
control
S
P
To
Process
Low
pressure
control
Optional
CPR valve
Bypass
Refrigeration
access valve,
Compressor
compressor-mounted
From
Process
Pump
SMC Series Chillers
Page 21
Figure 10
Piping Schematic — No Pump, No Reservoir
Air-cooled condenser
Discharge line
Liquid line
Refrigeration
evacuation valve
Relief
valve
Refrigeration
evacuation valve
Filter
Filter
drier
Suction
line
Expansion
valve
Legend
Sight
glass
Refrigeration lines
Chilled water piping
Condenser water piping
End of unit piping
Evaporator
Equalizing line
Power element
Refrigeration
access valve
Optional
pressure
gauge
Temperature
Probe
TC
High
pressure
control
P
S
To
Process
Low
pressure
control
Bypass
Optional
CPR valve
Refrigeration
access valve,
Compressor
compressor-mounted
Flow
switch
From
Process
Page 22
SMC Series Chillers
4
Startup Checklists
4-1 Introduction
Follow the check lists below for the startup of your new chiller. These lists assume the
installation information elsewhere in this manual has been read and followed. New chillers
should be started up and checked by a qualified refrigeration service technician.
4-2 SMC Pre-Startup Checklist
1. Check the shipping papers against the serial tag to be sure chiller size, type and voltage is
correct for the process that will be controlled.
2. Check the transformer primary voltage connections to be sure they are configured for the
electrical power you are using. The voltage at the main power connection must read
within +/-10% of the voltage listed on the serial tag. Electrical connections must conform
to all applicable codes.
3. The chilled water TO PROCESS and FROM PROCESS connections should be completed.
4. Be sure the reservoir tank and chilled water circuit piping are filled with water.
5. The air-cooled condenser should have an adequate supply of air for proper operation.
6. Connect main power to the chiller and run the chiller just long enough to see if the pump
is generating normal pressure.
7. Check your work and proceed to the SMC Startup Checklist section below.
4-3 SMC Startup Checklist
1. Turn ON the chiller. The SMC chiller should continue to run until the switch is turned
OFF.
2. Put the SMC chiller under a process load.
3. Set the microprocessor control to the desired process temperature setpoint using the
,
, and
buttons. See Chapter 5 on Page 27 for more information.
4. Check the pump amp draw and pump pressure. The amp draw reading must be within the
running load and service factor amps.
5. Operate the chiller, looking for leaks and listening for unusual noises or vibrations that
could indicate improper operation.
SMC Series Chillers
Page 23
Figure 11
SMC Water Circuit Pressure Drop Table
Model
Gallons per minute
∆P (psig)
2.5
2.0
2.4
3.6
4.8
2.0
2.4
3.6
4.8
2.0
2.4
3.6
4.8
4.0
7.5
12.5
2.5
2.5
3.0
5.0
2.5
2.5
SMC050A
SMC100A
SMC150A
3.0
3.5
Page 24
SMC Series Chillers
5
Microprocessor Control
5-1 Introduction
Standard SMC Series chillers use a microprocessor based controller. The controller is a modular,
self-contained unit that can slide from its mounting housing. It is factory set and adjusted; no
field adjustment to the internal controls is necessary.
5-2 Setting the Process Water Temperature
• Press
until the SP indicator lights.
or to raise or lower the setpoint to the desired leaving water
• Press
temperature.
Note: SMC leaving water temperature range of operation is 30ºF (-1°C) to 65ºF (18°C).
• Press to display the current process temperature (SP and AL are off).
5-3 Setting the Alarm Value
• Press
until AL lights.
or to raise or lower the alarm value. The factory setting is 10, and
• Press
should be correct for most processes. Setting the alarm value to 10 creates an alarm if the
process temperature rises or falls 10ºF/ºC or more from the chiller process setpoint.
• Press
to display the current process temperature (SP and AL are off).
SMC Series Chillers
Page 25
Figure 12
SMC Control
Lights when the display
shows the alarm value
Lights if Process Temperature
is above the set point
Compressor On indicator
C°
ON
AL
Process temperature is 10°
or more above the set point
Lights when Process Temp is
within +/- 1% of the full scale
Lights if Process Temperature
is below the set point
Increases the process set point
or alarm value
SP AL
Lights when the display
Lowers the process set point
or alarm value
shows the process set point
OMRON E5CS
Scroll -- Steps Through Process
set point, actual temperature,
and alarm value displays
Page 26
SMC Series Chillers
6
Optional Graphic Panel
6-1 Indicator Lights
PUMP ON (green)
This indicator is lit when the pump runs.
COMPRESSOR ON (green)
This indicator is lit when the compressor operates.
HIGH REFRIGERANT PRESSURE (red)
This indicator lights if the condensing pressure exceeds a safe level. The chiller goes to Idle
mode until the high refrigerant pressure cutout resets. The light then goes out and the chiller
automatically restarts. Call a qualified refrigeration service technician for service.
LOW REFRIGERANT PRESSURE (red)
This indicator lights if the refrigerant pressure drops below a safe level. The compressor will stop
and remain off until the pressure reaches a safe level. The light will go out and the chiller will
then resume operation automatically.
LOW WATER FLOW (red), SMC units without pump only
This indicator lights if the flow switch senses chilled water/glycol flow through the evaporator
dropping to an unacceptable level. The compressor will stop until the flow switch senses
adequate flow and restarts the chiller.
6-2 Switches
POWER
This switch energizes the control circuit; it also turns off the chiller.
SMC Series Chillers
Page 27
Figure 13
Optional Graphic Panel
SMC Series
Portable Chiller
ON
LOW
HIGH
ON
PUMP
ON
COMPRESSOR
ON
REFRIGERANT
PRESSURE
REFRIGERANT
PRESSURE
AL
POWER
O
RO E5CS
OFF
A0537868
Page 28
SMC Series Chillers
7
Routine Maintenance
7-1 Lubrication
Every three months, grease all fan motors and pump motors that do not have permanently sealed
bearings. Remove grease relief plug (motors only) before adding grease. Failure to do so may
result in dislodging the bearing grease retainer, eventually causing bearing failure.
Compressors are hermetically sealed; no oiling is required.
7-2 Condenser Maintenance
Dirty condenser heat exchange surfaces reduce system capacity.
Brush or vacuum light dirt accumulations. Avoid bending or damaging the fins. Heavy soil
accumulations on the coil require professional steam cleaning; washing from the outside only
makes matters worse.
Figure 14
Typical SMC Subpanel
Distribution
Block
Grounding
Lug
Terminal
Blocks
Control Voltage
Transformer
Pump
Contactor
Condenser
Contactor
SMC Series Chillers
Page 29
Figure 15
Typical SMC Wiring Schematic
1C
1L1
1T1
Pump
1MTR
2MTR
3MTR
1L2
1T2
2T1
2C
1L1
Compressor
1L2
2T2
3T1
Earth
ground
Fan
3T2
Remote
interlock
by others
1L2
1L1
230V
Control
power
ON/OFF
1T
Subpanel
ground
Jumper
1FU
1S-1LT
2
1
X1
115V
2
1S-1LT
"Power On"
G
Pump
starter
3
1C
"Low Refrig
Pres"
"Hi Refrig
Pres"
2LT
G
"Pump On"
3LT
4LT
R
R
1PS
2PS
Condensing unit
contactor
4
5
6
2C
G
5LT
"Compressor On"
6
1
7
2
8
9
4
10
5
1CNTL
Jumper
3
Legend
Customer wiring/Customer-supplied components
Optional components
(+)
YEL
(-)
RED
Type K Thermocouple
Page 30
SMC Series Chillers
Figure 16
SMC Wiring Schematic for Chillers with No Pump or Reservoir
1C
1L1
1T1
Compressor
1MTR
2MTR
1L2
1T2
2T1
1L2
1L1
Fan
Remote
interlock
by others
Earth
ground
2T2
230V
115V
Control
power
ON/OFF
1T
Subpanel
ground
Jumper
1FU
1S-1LT
2
2
1
X1
1S
1S-1LT
G
"Power On"
"Low Refrig
Pres"
"High Refrig
Pres"
31
"No Flow"
2LT
3LT
4LT
R
R
R
1FLS
1PS
2PS
Condensing unit
contactor
4
5
5
6
7
1C
G
5LT
"Compressor On"
2
Legend
6
7
2
8
9
4
10
5
Customer wiring/Customer-supplied components
Optional components
Jumper
3
1CNTL
1
(+)
(-)
YEL
RED
Type K thermocouple
SMC Series Chillers
Page 31
- Notes -
Page 32
SMC Series Chillers
8
Troubleshooting Guide
Problem
Possible cause
No power.
Solution
Check main disconnect
fuses, wiring, and power lead
to the unit.
Voltage must be within plus
or minus 10% of the
nameplate rating.
Replace.
Wrong voltage supplied to
the chiller.
Chiller will not run.
Defective on/off switch.
Replace, check the
transformer.
Control circuit fuse blown.
Defective control transformer. Replace.
No process load on the
chiller.
Refrigerant is low.
Refrigerant is low.
Increase the process load.
Pump runs, compressor
cycles at short intervals.
Check the refrigerant charge.
Check the refrigerant charge.
Make sure that the coolant
solution is right for the
process — must be 75%
water and 25% glycol.
The leaving water
temperature is too high.
Improper water/glycol
solution.
See Figure 5 on Page 17 for
more information.
Pump pressure is low (see
pump curves).
Check for foreign matter.
Restricted water flow.
Clean the system.
Check for partially closed
valves, etc. Be sure all lines
are properly sized.
Pump pressure is too high.
SMC Series Chillers
Page 33
Problem
Possible cause
Refrigerant is low.
Solution
Check the refrigerant charge.
Sight glass should be clear
Pressure switch contacts are while compressor runs. Call
open.
for service if bubbling or
foaming.
Refrigerant high pressure
cutout switch contacts are
open.
Check for dirty condenser.
Check for condenser air
obstruction.
Pump runs, compressor will
not.
Defective fan motor.
Repair or replace.
Check for high/low voltage.
Compressor internal overload Must be within plus or minus
is open. Allow time to cool
and reset.
10% of the nameplate rating.
Check for poor compressor
electrical connections.
Broken wire in the
compressor control circuit.
Locate and repair.
Restricted condenser airflow. Clean the condenser.
Unit low on refrigerant.
Inefficient compressor.
Unit undersized for
application.
Call Service.
Call Service.
Unit runs continuously, but
not enough cooling power.
Call Sales Representative.
Page 34
SMC Series Chillers
Figure 17
SMC Spare Parts List
Part number
A0537868
A0537899
A0534584
A0534586
A0500857
A0534269
A0537955
A0533873
A0539409
A0103778
A0537900
A0537908
A0537915
A0543063
A0537916
A0537917
A0501642
A0104093
A0537974
Description
SMC graphic
BZ pressure gauge
Red neon graphic light *
Green neon graphic light *
2” swivel casters
1/16 DIN digital temperature controller
Process water flow switch
Thermocouple, 8’
150 VA transformer
Rubber feet
Tank sight glass assembly
Handles
SMC050A-SMC100A low refrigerant pressure switch
SMC150A low refrigerant pressure switch
SMC050A-SMC100A high refrigerant pressure switch
SMC150A high refrigerant pressure switch
SMC050A-SMC100A high refrigerant pressure safety relief valve
SMC150A high refrigerant pressure safety relief valve
Bronze Y strainer
* Units with the optional SMC graphic panel.
SMC Series Chillers
Page 35
Service Notes
Page 36
SMC Series Chillers
Service Notes
SMC Series Chillers
Page 37
Parts Department
[
]
[
]
Call toll-free 7am–6pm CST 800 783-7835 or call 414 354-0970
The Sterling/Sterlco Parts Department at Sterling, Inc. is ready to provide the parts to keep your systems up and
running. Sterling/Sterlco replacement parts ensure operation at design specifications. Please have the model and
serial number of your equipment when you call. Consult the Customer Parts List included in your information packet
for replacement part numbers.
Service Department
[
]
[
[
]
]
Call toll-free 8am–5pm CST 800 783-7835 or call 414 354-0970
Emergencies after 5pm CST, call 847 439-5655
Sterling/Sterlco has a qualified service department ready to help. Service contracts are available for most Sterling/
Sterlco products.
Sales Department
[
]
Call 414 354-0970Monday–Friday, 8am–5pm CST
Sterling/Sterlco products are sold by a world-wide network of independent sales representatives. Contact our Sales
Department for the name of the sales representative nearest you.
Sterling/Sterlco
5200 West Clinton Avenue
Sterling
Milwaukee, WI 53224-9518
[
]
[
]
414 354-0970 • Fax 414 354-6421
Page 38
SMC Series Chillers
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