System Maintenance Procedure for Walk in Type Stability Chamber

1. GENERAL MAINTENANCE

Only Trained and Skilled Persons Should Maintain the Machine

Follow the work permit procedure before any maintenance work. 

1. Clean the chamber from inside and outside after use.
2. Check the incoming electric supply of 230 V AC with Neutral and proper earthing.
3. The environment should be with proper exhaust fan or air conditioner.
4. Clean the condenser by blowing air through it after every 2 months.
5. Check whether the air-circulating blower in the AHU is tightened.
6. Check the operation of the safety thermostat with reference from OQ.
7. Connect proper earthling to the Walk in Type Stability Chamber
8. Connect drainpipe connection.
9. Close the chamber door properly.
10. Check whether the side port hole is properly fitted with rubber cock.
11. Calibration and Validation of the Walk in Type Stability Chamber should be done once in a year before the expiry of the due date mentioned.

2. TROUBLESHOOTING

No.	REASON	CORRECTIVE ACTIONS
2.1  HEATING EFFECT NOT ACHIEVED.
2.1.1	MCB may have trip.	Check the MCB (501&502) If found trip, switch ON it.
2.1.2	DC output not available.	Check the 24 VDC output from the SMPS (850&851). Check the MCB. If found trip, switch ON it.
2.1.3	SSR not working.	The DC supply goes from the CPU (951) to the input of SSR. The SSR is provided with phase connection (502&504) goes to the Air Heater. If the CPU (951) is giving 24 Volts DC to the SSR input and then checks which SSR output terminal (504) is not showing the phase (230 Volts) it means that SSR is not working, this has to be replaced.
2.1.4	Air heater not working.	The phase from the output of the SSR (504) is given to the heater and the neutral (400) is directly connected. In case the phase and neutral is provided and still heater is not heating up, it means, that heater is broken. Also check the heater continuity with the body. If not proper, then replace the heater.
2.1.5	Safety Thermostat is not Working.	Check the safety thermostat and if found not working replace it.
2.1.6	Chamber motor not working.	Check the Motor winding, if found burned out or found any problem replace it. Check the starting capacitor, If found faulty, replace it. Check the MCB (601&612) If found trip, switch ON it.
2.2   HUMIDITY EFFECT NOT ACHIEVED WITH REGULAR SYSTEM.
2.2.1	MCB may have trip.	Check the MCB (550&551) if found trip, switch ON it.
2.2.2	DC output not available.	Check the 24 VDC output from the SMPS (850&851) Check the MCB. If found trip, switch ON it.
2.2.3	SSR not working.	The DC supply goes from the CPU (952) to the input of SSR. The output of the SSR is provided with a phase connection coming from the relay RL5 (552) and the other output (554) goes to the Heater. If the CPU (952) is giving 24 Volts DC to the SSR input and the SSR output terminal is not showing the phase (230 Volts) it means that SSR is not working, it has to be replaced.
2.2.4	Relay not working.	The DC supply goes from the CPU (954) to the input of Relay (RL5). The common point of the Relay is provided with a phase connection (551) and the output (552/NO) goes to the SSR. If the CPU (954) is giving 24 Volts DC to the Relay input and also present the supply (551).But the Relay (NO/552) output terminal is not showing the phase (230 Volts) that means the Relay is not working, this has to be replaced.
2.2.5	Heating element not working.	The phase from the output of the SSR (554) is given to the heater and the neutral (400) is directly connected. In case the phase and neutral is provided and still heater is not heating up, that means, heater is broken. Also check the heater continuity with the body. If not proper, then replace the heater.
2.2.6	12 Volt DC output is not available to the RH sensor.	12 Volt DC to the sensor is supplied from a 12 VDC power supply if 12 V is not available at the output of the 12 VDC power supply replace it.
2.2.7	RH sensor is not working	RH sensor output should be between 0 to 1 VDC. Checking of RH sensor output should be done on Green and Black wire. If the output of RH sensor is not obtained replace it.

2.3   HUMIDITY EFFECT NOT ACHIEVED WITH STAND BY SYSTEM
2.3.1	MCB may have trip.	Check the MCB (550&571) if found trip, switch ON it.
2.3.2	DC output not available.	Check the 24 VDC output from the SMPS (850&851) Check the MCB. If found trip, switch ON it.
2.3.3	SSR not working.	The DC supply goes from the CPU (952) to the input of SSR. The output of the SSR is provided with a phase connection coming from the relay RL 6 (572) and the other output (573) goes to the Heater. If the CPU (952) is giving 24 Volts DC to the SSR input and the SSR output terminal is not showing the phase (230 Volts) it means that SSR is not working, it has to be replaced.
2.3.4	Relay not working.	The DC supply goes from the CPU (955) to the input of Relay (RL6). The common point of the Relay is provided with a phase connection (571) and the output (572/NO) goes to the SSR. If the CPU (955) is giving 24 Volts DC to the Relay input and also present the supply (571).But the Relay (NO/572) output terminal is not showing the phase (230 Volts) that means the Relay is not working, this has to be replaced.
2.3.5	Heating element not working.	The phase from the output of the SSR (573) is given to the heater and the neutral (400) is directly connected. In case the phase and neutral is provided and still heater is not heating up, that means, heater is broken. Also check the heater continuity with the body. If not proper, then replace the heater.
2.3.6	12 Volt DC output is not available to the RH sensor.	12 Volt DC to the sensor is supplied from a 12 VDC power supply if 12 V is not available at the output of the 12 VDC power supply replace it.
2.3.7	RH sensor is not working	RH sensor output should be between 0 to 1 VDC. Checking of RH sensor output should be done on Green and Black wire. If the output of RH sensor is not obtained replace it.
2.4  COOLING EFFECT NOT ACHIEVED WITH REGULAR REFRIGERATION SYSTEM
2.4.1	MCB may have trip.	Check the MCB (601&604), if found trip, switch ON it.
2.4.2	Relay not working.	The DC supply goes from the CPU (956) to the input of Relay (RL7). The common point of the Relay is provided with a phase connection (604) and the output (605/NO) goes to the SSR1. If the CPU (956) is giving 24 Volts DC to the Relay input and also presents the supply (604). But the Relay (605/NO) output terminal is not showing the phase (230 Volts) that means the Relay is not working, this has to be replaced.
2.4.3	Overload or the capacitor of the compressor not working.	Check compressor of regular cooling system for overload and starting and running capacitor for the supply to the compressor. If found faulty, replace it.
2.4.4	Condenser Motor not working	Check the Motor winding, if found burned out or found any other problem replace it. Check the starting capacitor, If found faulty, replace it
2.4.5	DC output not available.	Check the DC output from the temperature controller terminals 13 (344) and 14 (345). (Hydronic system)
2.4.6	SSR not working.                        (Hydronic system)	The DC supply comes from the temperature controller terminal 13 (344) and 14 (345) to SSR terminal 3(+) & 4(-). The output of the SSR is provided with a phase connection (605) coming from the relay RL 7 and the other output (606) goes to the compressor. If the controller is giving DC volt to the SSR input and the SSR output terminal is (606) not showing the phase (230 Volts) that means the SSR is not working, this has to be replaced.
2.4.7	Chilled water circulation pump not working. (Hydronic system) Note: - One number water pump is working at a time.	Check the water pump winding. Check the starting capacitor. Check for any water line chock up or dust accumulate inside the impeller.
2.4.8	Unavailability of chilled water.	Check the water level inside the Chiller tank. Check for any water leakage from the pipe connection.

2.5  COOLING EFFECT NOT ACHIEVED WITH STAND BY REFRIGERATION SYSTEM
2.5.1	MCB may have trip.	Check the MCB (601&623), if found trip, switch ON it.
2.5.2	Relay not working.	The DC supply goes from the CPU (957) to the input of Relay (RL8). The common point of the Relay is provided with a phase connection (623) and the output (624/NO) goes to the SSR2. If the CPU (957) is giving 24 Volts DC to the Relay input and also presents the supply (623). But the Relay (624/NO) output terminal is not showing the phase (230 Volts) that means the Relay is not working, this has to be replaced.
2.5.3	Overload or the capacitor of the compressor not working.	Check the compressor of stand by cooling system for overload and starting and running capacitor for the supply to the compressor. If found faulty, replace it.
2.5.4	Condenser Motor not working	Check the Motor winding, if found burned out or found any other problem replace it. Check the starting capacitor, If found faulty, replace it
2.5.5	DC output not available.	Check the DC output from the temperature controller terminals 13 (344) and 14 (345). (Hydronic system)
2.5.6	SSR not working.                       (Hydronic system)	The DC supply comes from the temperature controller terminal 13 (344) and 14 (345) to SSR terminal 3(+) & 4(-). The output of the SSR is provided with a phase connection (624) coming from the relay RL8 and the other output (625) goes to the compressor. If the controller is giving DC volt to the SSR input and the SSR output terminal is (625) not showing the phase (230 Volts) that means the SSR is not working, this has to be replaced
2.5.7	Chilled water circulation pump not working. (Hydronic system) Note: - One number water pump is working at a time.	Check the water pump winding. Check the starting capacitor. Check for any water line chock up or dust accumulate inside the impeller.
2.5.8	Unavailability of chilled water.	Check the water level inside the Chiller tank. Check for any water leakage from the pipe line connection.
2.5.9	Controller not working.                  (Hydronic system)	Check the Pt 100 sensor.(Inside the chiller tank) Check the set point. (as per the set condition)
2.6   CHAMBER MOTOR NOT WORKING
2.6.1	Chamber motor not working.	Check the MCB (601 & 612). If found trip, switch it ON.
2.6.2	Starting capacitor not working.	Check the starting capacitor, If found faulty, replace it.
2.6.3	Motor burned out.	Check the Motor winding, if found burned out or found any problem replace it.

2.7 PLC PUMA / PUME NOT WORKING
2.7.1	No 24V DC Power supply to PUMA / PUME	Check the MCB (312 & 313). If found trip, switch ON it. Check SMPS 24V DC. If found faulty replace it.
2.7.2	PUMA / PUME not function properly	PUMA / PUME program may be corrupt. Reload the program.
2.8  HMI (HUMAN MACHINE INTERFACE)
2.8.1	No Display	Check 24V DC power (850 & 851). If not check the wire for open, 24V DC output from SMPS. If not replace it.
2.8.2	Communication Failure	Communication cable faulty. Replace it.
2.8.3	No printing	Printer cable may be faulty or loose, reconnect or replace it.
2.8.4	Any of the Sensor values are not showing proper	Wiring connections may be loose or sensor may be faulty, reconnect or replace it
2.9   PLC NOT FUNCTIONING PROPERLY
2.9.1	PLC not functioning as per program	Check the electrical connection to PLC, if not proper then make proper connections as per electrical diagram, check whether any loose connections.

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