maintenance of various equipments installed at 220 kv sub station hardoi and 132kv sub station shrimau - 1 following works is to be carried out for maintenance of ac installed at 220 kv sub station, hardoi and 132 kv sub-station, shrimau  cleaning and checking outdoor & indoor unit, washing and cleaning of air filter of 02 ton capacity hitachi make split air conditioner with nylon brush soap and repairing of deteriorated, if required with skilled technician. 2 checking of leakage for refrigerant ( r22 ) gas and brazing of any leakage joint perfectly & recharging of refrigerant gas in sufficient quantity in compressor of 02 ton capacity hitachi make split air conditioner including cost of material and skilled technician. 3 repairing / replacement of control unit ( pcb ) and oen relay of 5kva-230v stabilizer. 4 replacemnt of damaged refrigerant gas pipe made of copper outdoor to indoor unit including cost of material , skilled technician and t&p 5 replacement of damaged capacitor of electrically outdoor unit. 6 replacement of damaged pvc pipe from outdoor unit with best quality of pvc pipe for draining of water. 7 replacement of damaged compressor suitable for 02 ton split ac ( hitachi make ) 8 repairing of damage outdoor unit 9 replacement of damaged condensor heating coil alongwith broken blower.