sop for preventive maintenance of air handling units

1.0 Objective 
To lay down a procedure for the Preventive Maintenance of AHU system, and Ventilation Exhaust and supply
2.0 Scope
This Standard Operating Procedure is applicable for the Preventive Maintenance of below mentioned equipments installed   to be followed at formulation plants
2.1 Air Handling System
2.2 Ventilation Unit (Supply & Exhaust)
3.0 Responsibility
3.1 Engineering Officer / Executive shall be responsible for the execution of this procedure.
3.2 Engineering Manager shall be responsible for the compliance of this SOP.
3.3 Head QA/designee shall be responsible for the compliance of this SOP.
4.0 Abbreviations and Definitions
SOP : Standard Operating Procedure
No : Number
QA : Quality assurance
Qty : Quantity
AHU : Air Handling Unit
HP/LP : High pressure and Low pressure
DX : Direct Expansion
5.0 Procedure
5.1 Inform the user department, put the main power supply of the unit to ‘OFF’ and display “UNDER MAINTENANCE” board over the panel and allow the blower to come to rest.
5.2 Preventive maintenance of AHU system should be carried out as per preventive maintenance master schedule.
5.3 Technician should carry out the Preventive Maintenance work on the AHU system as per Preventive Maintenance master schedule.
5.4 Technician has to visually check the machine and system should be in cleaned condition.
5.5 Take proper safety precautions/ measures prior to carry out the preventive maintenance work like Isolation of Electric power and Utilities (Compressed air, Chilled water) wherever applicable.
5.6 Lint free cloth to be used for cleaning.
5.7 Visually check the machine and the surrounding area is thoroughly cleaned after preventive maintenance work.
5.8 Officer / Executive should check the Preventive Maintenance work is done as per the preventive maintenance.
5.9 Incomplete preventive maintenance work due to shortage of spares and delay in fabrication / modification work to be recorded. The same should be communicated to the Engineering Manager by Engineering Officer / Executive.
5.10 The preventive maintenance of AHU system should be deferred by a week under the following conditions.
5.10.1 Non availability of machine
5.10.2 Non availability of critical spares.
5.10.3 Holiday
5.11 Any other reason, the reason for deferred preventive maintenance for the AHU systems should be mentioned by the officer in the preventive maintenance record and it should be acknowledged by Engineering Manager.
5.12 Quarterly maintenance shall be carried out as per following points.
5.12.1 Clean the filters as per the respective SOP.
5.12.2 Check and tight the motor & blower foundation bolts.
5.12.3 Check the “V” belt condition for tightness, if required replaces the same.
5.12.4 Check the Door gaskets for any leakage, if required replace the same.
5.12.5 Check the motor bearings. If required Lubricate with grease/ replace the bearings.
5.12.6 Check all electrical connections (control panel, all motors,) for any loose connections, burned contacts, signs of overheated wires etc. Tight/replace the same.
5.12.7 Check the manometer tube gauge tubes, if required replace the tubes.
5.12.8 Check and clean the cooling coil fills with compressed Air & water.
5.12.9 Check the proper earthing.
5.12.10 Start the unit and check the magnehaulic gauge the reading should be below 20mm.
5.13 Record all the observation in Preventive Maintenance checklist as per Annexure-1.
6.0 Forms and Records
6.1 Quarterly Preventive Maintenance Check list of AHU – Annexure-1
7.0 Distribution
7.1 Master copy – Documentation Cell (Quality Assurance)
7.2 Controlled copies – Engineering Department