York YLPA 0115SE, Installation, Operation And Maintenance Manual

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68
JOHNSON CONTROLS
FORM 150.68-ICOM1
ISSUE DATE: 10/15/2020
SCHEDULED MAINTENANCE
The maintenance operations detailed in the following table should be performed on a regular basis by a suitably
qualified Service Engineer. It should be noted that the interval necessary between each ‘minor’ and ‘major’ service
can vary depending on, for instance, application, site conditions and expected operating schedule. Normally a ‘minor’
service should be carried out every three to six months and a ‘major’ service once a year. It is recommended that
your local Johnson Controls Service Center is contacted for recommendations for individual sites.
HEAT EXCHANGER IN-SERVICE INSPECTION
There is no corrosion on the refrigerant side therefore in-service inspection on the refrigerant side is not necessary.
For the water side, if the water used is treated in accordance with Section 4, in-service inspection is not necessary.
In the design of the vessels used in the unit, a 1 mm corrosion allowance has been used to consider slight corrosion
on the water side. This allowance is sufficient to cover the lifetime of the unit.
Johnson Controls believes that periodic in service proof testing (e.g.; hydro tests) is not required. However, Johnson
Controls recognizes that national regulations may require such testing to be conducted.
MAJOR SERVICE
All items under Minor Service plus:
Unit general: Check thermal insulation. Check main structure.
Check vibration isolators. Check paint-work.
Refrigerant systems general: Check relief valves. Check solenoid valves.
Check for pipework damage.
Check for leaks.
Check moisture indicator.
Check suction superheat.
Check liquid subcooling.
Compressors: Check oil level.
Check condition of oil.
Heat Exchanger: Check water flow. Check water pH / glycol strength.
Check water pressure drop.
Check heater mats.
Ambients coils: Check for airflow obstructions. Brush fins.
Check fins. Check fan motor bearings.
Check fans and fan guards.
Power & Control system general: Check panel condition. Check all connections.
Check mains and control wiring. Check compressor contactors.
Check sensor locations. Check fan contactors
Check mechanical HP cut-outs. Check sensor / transducer calibration.
Check motor protectors.
Check contactor contacts.
Microprocessor controls: Check fault history. Check fan control function.
Check program settings. Check ambient cut-out function.
Check HP / LP cut-out function’s.
Check load / unload function.
SERVICE SCHEDULE MINOR SERVICE