SRL Service Manual Revision 00 July 2007 Table of Contents 1. General Description 2. Specifications 2.1 Model Range 2.1.1 60 Hz Models 2.1.2 50 Hz Models 2.2 Operating Limits 2.3 Technical Specifications 2.3.1 60 Hz Air Cooled Models 2.3.2 60 Hz Water Cooled Models 2.3.3 50 Hz Air Cooled Models 2.3.4...
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SRL Service Manual Revision 00 July 2007 4. Control System 4.1 Power Supply 4.3 Microprocessor Controls 4.2.1 Inputs 4.2.2 Outputs 4.2.3 Electrical Specifications 4.2.4 User Interface 4.2.4.1 Lights 4.2.4.2 Buttons 5. Installation 6. Start Up 7. Operation & Control 7.1 Turning the Dryer On or Off 7.2 User Parameter List 7.3 Accessing &...
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SRL Service Manual Revision 00 July 2007 10.3 Service Required Warning (Sr) 10.3.1 How to Reset the Service Required (Sr) Warning 10.3.2 How to Change the Service Required (Sr) Warning Interval 10.4 Alarm History Report 10.4.1 Viewing the Alarm History Report 10.3.2 Resetting the Alarm History Report 10.5...
Revision 00 July 2007 1. General Description The Sullair SRL Refrigerated Air Dryer reduces the dew point of a compressed air stream by reducing the temperature causing water and oil vapour (along with other evaporated contaminants) to condense into liquids. These liquids are then separated from the air and discharged from the system.
SRL Service Manual Revision 00 July 2007 Specifications 2.1 Model Range 2.1.1 60 Hz Models Rated Pressure Absorbed Port Sullair Voltage Condenser Flow [1] Drop Power Size Model Part # Volt Ph Hz AC/WC (scfm) (psid) (kW) (in) 02250169-434 02250169-435 SRL-250 1.78...
SRL Service Manual Revision 00 July 2007 2.1.2 50 Hz Models Rated Pressure Absorbed Port Sullair Voltage Condenser Flow [1] Drop Power Size Model Part # Volt Ph Hz AC/WC (m3/min) (mbar) (kW) (in) SRL-120 02250169-405 400 1.41 2" SRL-140 02250169-406 400 1.37...
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SRL Service Manual Revision 00 July 2007 2.3.2 60 Hz Water Cooled Models Type R407C Refrigerant Charge lb (kg) 9.26 (4.2) 7.72 (3.5) 14.33 (6.5) Quantity Expansion Capillaries 3.18 Internal Diameter Length 1200 2800 2000 psig (barg) 62.4 (4.3) Hot Gas Valve Setting psig (barg) 66.7 (4.6) 33.8 (1)
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SRL Service Manual Revision 00 July 2007 2.3.3 50 Hz Air Cooled Models Type R407C Refrigerant Charge Quantity Expansion Capillaries Internal Diameter 3.18 3.18 Length 1500 4000 1500 1000 2800 barg Hot Gas Valve Setting barg °C Suction Temperature °C °C Discharge Temperature °C...
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SRL Service Manual Revision 00 July 2007 2.3.4 50 Hz Water Cooled Models R407C Type Refrigerant Charge Quantity Expansion Capillaries Internal Diameter 3.18 3.18 Length 4000 2000 1000 2800 barg Hot Gas Valve Setting barg °C Suction Temperature °C °C Discharge Temperature °C °C...
SRL Service Manual Revision 00 July 2007 3. System Design The SRL dryer consists of two circuits: the Air Circuit and the Refrigeration Circuit: Refrigerant Circuit Circuit The refrigerant The liquids condense cools the air. & are drained away. • The Air Circuit: Consisting primarily of: A.
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SRL Service Manual Revision 00 July 2007 3.1 The Air Circuit The SRL is unique in that it’s entire air circuit is combined into a single compact 4-in-1 unit, combining: • the Air-to-Air Heat Exchanger, • the Air-to-Refrigerant Heat Exchanger, •...
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SRL Service Manual Revision 00 July 2007 3.1.1 Air-to-Air Heat Exchanger The Air-to-Air Heat Exchanger is an aluminium fin, cross flow exchanger. The Air-to-Air Heat Exchanger is also often called a “Pre-cooler / Re-heater” because the hot air entering the dryer is pre- cooled by the cold air exiting the dryer;...
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SRL Service Manual Revision 00 July 2007 3.1.5 Dew Point Temperature Sensor All models have a Dew Point Temperature Sensor that measures the temperature of the air leaving the Air-to-Refrigerant Heat Exchanger. At this point in the dryer, the temperature of the air is theoretically equivalent to what the outlet dew point will be.
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SRL Service Manual Revision 00 July 2007 3.2.1 The Thermal Mass Concept The combined air side heat exchanger assembly serves an additional purpose as a “Thermal Mass” – that is a mass of material with high thermal retention – or the capacity to absorb a significant quantity of heat without a rapid rise in temperature.
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SRL Service Manual Revision 00 July 2007 3.2.3 Condenser The condenser cools the refrigerant causing it to condense back to a liquid. The SRL-700 through 6000 (60Hz) and SRL-220 through 1800 (50Hz) can be purchased with either an air cooled or water cooled condenser.
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SRL Service Manual Revision 00 July 2007 3.2.5 Expansion Device The expansion device reduces the pressure (and therefore temperature) of the refrigerant and regulates it’s flow into the Air-to-Refrigerant Heat Exchanger. All models use a capillary tube expansion device. The capillary tube is a copper tube of precise length and diameter that provides a specific pressure drop and choked flow rate.
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SRL Service Manual Revision 00 July 2007 3.2.9 Fan Pressure Switch (Air Cooled Models) Settings: On: 275 psig (19 barg), Off: 203 psig (14 barg). Controls operation of the condenser fan which keeps the pressure (and therefore temperature) of the refrigeration circuit within design limits. Turns the fan on when the refrigerant pressure reaches 275 psig (19 barg) and off when it reaches 203 psig (14 barg).
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SRL Service Manual Revision 00 July 2007 3.2.12 Liquid Accumulator The SRL-700 to 6000 (60Hz) and SRL-220 to 1800 (50Hz) have a liquid accumulator in the refrigerant suction line before the compressor. Even though the compliant scroll compressor can handle some liquids, this prevents large volumes of liquids from reaching the inlet.
All 50 Hz models are 400V/3ph/50Hz +/-10%. Microprocessor Controls The microprocessor controls on the Sullair SRL Dryers allow you to turn the dryer on and off, controls the operation of the dryer, and continuously monitors the working parameters, informing the user of possible problems through lights, alarms and a digital display.
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SRL Service Manual Revision 00 July 2007 4.2.1 Inputs Consists of both analog inputs (J2) and digital inputs (J1 & J3). Analog Inputs (J2) 1 GND Ground for temperature sensors. 2 B1 Dewpoint Temperature Sensor (B1) 3 B2 Evaporator Temperature Sensor (B2) 4 B3 Compressor Discharge Temperature Sensor (B3) 5 B4...
SRL Service Manual Revision 00 July 2007 4.2.3 Electrical Specifications Power Supply 24 Vac ± 20% Temperature Sensors B1,B2 & B4: Reading Range C to +90°C ± 1°C Temperature Sensor B3: Reading Range 0°C to 150°C ± 5°C Input for HP, LP, CP & Remote On-Off 24 Vac Output for Drain Level Sensor 5Vc.c.
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SRL Service Manual Revision 00 July 2007 4.2.4.1 Lights Power LED o Yellow: indicates the dryer is off, but connected to a power supply. o Green: indicates the dryer is operating. Warning LED o Red: indicates the dryer has a warning or alarm. Drain LED o Green: indicates the drain valve is open.
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SRL Service Manual Revision 00 July 2007 4.2.4.2 Buttons Alarm Reset / Up o Standard Function: Resets Alarm or Warning. o In Alarm Menu: Scrolls up to previous alarm or item. o In Parameter Menu: Scrolls up to previous parameter or increases a value (when modifying a parameter).
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OFF position. • Install a Sullair 1 micron coalescing pre-filter (SCF or PF) immediately upstream of the dryer to prevent rust, pipe scale, bulk water, oil or other pollutants from entering the system and clogging the heat exchangers, separator, or condensate drain.
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SRL Service Manual Revision 00 July 2007 • If necessary, protect the dryer from vibration using vibration dampeners and/or flexible hoses on the inlet and outlet. • Also if necessary, protect the dryer from pulsation in the air stream by installing a upstream wet air receiver.
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SRL Service Manual Revision 00 July 2007 6. Start-up Before starting up the dryer, make sure that the air inlet and outlet isolation valves are closed, and the bypass valve is open. This will ensure there is no air flow through the dryer. For water cooled units do not open the isolation valves to allow cooling water to flow of water through the condenser until immediately before start up, otherwise, the HP (high pressure) alarm may occur.
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SRL Service Manual Revision 00 July 2007 7. Operation & Control 7.1 Turning the Dryer On or Off Turn the main switch to the “I/ON” position. For the first few seconds, the controller does an internal check, during which time the display shows “d.t.3”, indicating the version of the software installed.
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SRL Service Manual Revision 00 July 2007 7.2 User Parameter List Parameter Description Units Default Temperature Unit of Measure Dryer Working Hours Dryer Working Hours x 1000 hr x 10 Compressor Working Hours Compressor Working Hours x 1000 hr x 10 High Dewpoint (Hd) Warning Setting 0 / 32 70 / 158...
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(1) Parameters B3, B7 & B9 are passcode protected and cannot be changed or reset without the proper code. Contact Sullair for further information. (2) If you press Exit without first pressing Enter to save your changes, you will exit without saving and the parameter will revert to it’s previous value.
SRL Service Manual Revision 00 July 2007 8. Dryer Operating Modes In most applications, the air stream passing through the refrigerated dryer changes in pressure, temperature and flow rate throughout the day and throughout the year. This is due to external influences such as ambient temperature, and the pattern of usage of the air in the application.
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SRL Service Manual Revision 00 July 2007 8.2 Cycling Mode When Parameter C7 is set to “CYC” the dryer operates in cycling mode. In this mode the microprocessor reads the dew point, the temperature of the evaporator, and the time since the compressor was last turned off, and cycles the refrigerant compressor on and off as required to keep the temperature of evaporator between preset upper and lower temperature limits.
SRL Service Manual Revision 00 July 2007 9. Condensate Drain Operation 9.1 SRL-250 The SRL-250 has a solenoid valve (coil YV3) that is controlled as a timed drain by the microprocessor on the dryer. The user can adjust the operation of the drain by changing User Parameters D1 (Duration) and D2 (Interval) on the dryers control panel.
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SRL Service Manual Revision 00 July 2007 Every 100 cycles (Parameter D7 – Extended Cycle Interval), the microprocessor goes through an extended cycle, keeping the drain open for 10 seconds (Parameter D6 –Drain Close Delay [Extended Cycle]) after the level Sensor stops sending a signal. This allows the drain to periodically clean itself. If the drain has been open for 30 seconds and the Level Sensor still senses liquid (Parameter D8 –...
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SRL Service Manual Revision 00 July 2007 9.3 Drain Operating Mode (Parameter D3) Parameter D3 changes the operating mode of the condensate drain. There are 3 settings available for this parameter: Capacitive (Zero Air Loss): The drain solenoid valve (output YV3) is controlled by the level sensor (input ID4) found inside the integrated or external condensate chamber.
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SRL Service Manual Revision 00 July 2007 Alarms & Warnings 10.1 Alarm & Warning List Code Description Type Delay Action High Pressure Alarm None Stops Dryer. Low Pressure Alarm 2 min Stops Dryer. Low Dewpoint (B1) Alarm 3 min Stops Dryer. High Discharge Temperature (B3) Alarm None...
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SRL Service Manual Revision 00 July 2007 10.2 Troubleshooting Alarms & Warnings 10.2.1 High Pressure (Alarm) What it means: High pressure switch registers a refrigerant pressure above 406 psig (28 barg). What it does: Cuts power to compressor contactor & alarm contacts. Turns the dryer OFF. Turns on Warning Light &...
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SRL Service Manual Revision 00 July 2007 10.2.2 Low (Evaporator) Pressure (Alarm) What it means: Low pressure switch registers a refrigerant pressure below 22 psig (1.5 barg) for 2 minutes or more. What it does: Cuts power to compressor compressor contactor & alarm contacts. Turns dryer OFF.
SRL Service Manual Revision 00 July 2007 10.2.3 Low dewpoint (Alarm) What it means: Temperature sensor B1 (dew point temperature) registers a temperature below 28.4 F (-2 C) for 3 minutes or more. What it does: Cuts power to compressor contactor & alarm contacts. Turns dryer OFF. Turns on Warning Light &...
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SRL Service Manual Revision 00 July 2007 10.2.4 High (Discharge) temperature (Alarm) What it means: Temperature sensor B3 (compressor discharge temperature) registers a temperature above 248 F (120 What it does: Cuts power to compressor contactor & alarm contacts. Turns dryer OFF. Turns on Warning Light &...
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SRL Service Manual Revision 00 July 2007 10.2.5 Low (Evaporation) temperaure (Alarm) What it means: Temperature sensor B2 (evaporation temperature) registers a temperature below 27.5 F (-2.5 C) for 1 minute or more. What it does: Cuts power to compressor contactor & alarm contacts. Turns dryer OFF. Turns on Warning Light &...
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SRL Service Manual Revision 00 July 2007 10.2.6 Compressor Protection (Alarm) What it means: The compressor protection module registers a motor winding temperature above the allowable limit. What it does: Cuts power to compressor contactor & alarm contacts. Turns dryer OFF. Turns on Warning Light &...
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SRL Service Manual Revision 00 July 2007 10.2.8 High Dewpoint (Warning) Cause: Temperature sensor B1 (dewpoint temperature) is registering a temperature above the High Dewpoint Warning Setting (parameter A6: Default 15 C [59 F]) for more than 3 minutes. Result: Cuts power to the alarm contacts.
SRL Service Manual Revision 00 July 2007 10.2.9 drain Error (Warning) What it means: Drain Operating Mode (Parameter D3) is set to Capacitive (Zero Air Loss) Mode, and although the drain valve has been open for 30 seconds, the condensate level sensor is still registering condensate in the chamber.
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SRL Service Manual Revision 00 July 2007 10.2.10 Dewpoint Sensor Error (Warning) What it means: Temperature sensor B1 (dewpoint temperature) is short circuited, open, or a signal outside it’s range (-10 C to +90°C). What it does: Cuts power to the alarm contacts. Turns on Warning Light & alternates between “dSE”...
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Press ALARM RESET. Power restored to alarm relay & Warning Light goes off for 24 hours. To reset the alarm for another 6000 hours, contact Sullair or your authorized Sullair distributor and ensure the dryer & filters are inspected and maintained in accordance with the schedules in their respective user guides.
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SRL Service Manual Revision 00 July 2007 10.3 Resetting or Modifying the Service Required Warning (Sr) Every 6000 hours the dryer will display the “Sr” (Service Required) warning. The dryer will continue to function normally while this warning is displayed. The purpose of this warning is to ensure that the dryer is maintained in accordance with the maintenance schedule outlined in Section 10.1.
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SRL Service Manual Revision 00 July 2007 10.3.2 How to Change the Service Required (Sr) Warning Interval: 1) Press the Alarm Reset & Alarm Report buttons simultaneously to access the User Parameter & Menu. The display will show you are at Parameter “A1”. 2) Press the Down button repeatedly to scroll down to Parameter “B9”.
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SRL Service Manual Revision 00 July 2007 10.4 Alarm History Report 10.4.1 Viewing the Alarm History Each alarm or warning (with the exception of the Service Required Warning “Sr”) is recorded in the alarm report. The controller stores the last 8 alarms or warnings. New alarms will overwrite the oldest. For each alarm or warning, the controller stores the following data: •...
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SRL Service Manual Revision 00 July 2007 10.4.2 Resetting the Alarm History Please Note: The purpose of the Alarm History Report warning is to provide critical information to service personnel when troubleshooting the unit. For this reason, the procedure presented below is intended ONLY for authorized factory and distributor service technicians.
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SRL Service Manual Revision 00 July 2007 10.5 Remote Monitoring Option The SRL-250 to 6000 can be simply connected to an external supervisor system (otherwise known as BMS or Building Management System). To do so an (optional) RS485 serial card is fitted to the back of the microprocessor. This allows direct connection to a BMS using the MODBUS RTU protocol, without the need for any intermediate Gateway.
SRL Service Manual Revision 00 July 2007 11.2 Preventative Maintenance Kits In addition to the service requirements outlined above, proactive preventative maintenance can ensure continuous trouble free operation without unexpected alarms or failures. Three year preventative maintenance kits are available which include: •...
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SRL Service Manual Revision 00 July 2007 12. Maintenance Procedures 12.1 Replacing a Pressure Switch • When removing any pressure switch (High Pressure Switch [3.3.7], Low Pressure Switch [3.3.8] or Fan Pressure Switch [3.3.9]) use two spanners to avoid cracking the weld on the T joint. •...
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SRL Service Manual Revision 00 July 2007 12.4 Replacing the Control Board • Open the electrical box. • Remove the white connector containing the electrical supply & digital inputs & outputs. • Disconnect the temperature sensor wires. • Disconnect the level sensor (SRL-325 to 6000 ONLY) Pull firmly on the connector, being careful not to damage it.
SRL Service Manual Revision 00 July 2007 12.4 Adjusting the Hot Gas Bypass Valve The adjustment of the hot gas by-pass valve must be done without air flowing through the dryer. The 4.3 to 4.6 barg) for all models. pressure should be set between 62.4 and 66.7 psig ( •...
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In addition the sizing software can provide actual performance criteria of the dryer at the input operating conditions. Contact Sullair for further information. Page 59 of 56...
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SRL Service Manual Revision 00 July 2007 13.1 Correction Factors Ambient Temperature Correction Factor (A) Ambient Temperature ( Correction Factor “A” 1.30 1.23 1.16 1.08 0.92 0.89 Air Inlet Temperature Correction Factor (B) Air Inlet Temperature ( Correction Factor “B” 1.26 0.80 0.63...
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High Dew point alarm. You can tell him that he needs to call his local Sullair distributor and order an SRL-500, which would adequately handle his 300 cfm at these warm conditions (since 500 cfm x 1 x 0.63 x 1.03 = 324 cfm).
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