Air PreciseAIR PCA Series, Инструкция по установке, эксплуатации и обслуживанию

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IOM-PreciseAIR
Page 42 of 50
4.5. Filters
It is important to check filters on a regular basis and change when necessary, to ensure proper
operation of the unit.
Air Filter
Some units come with dirty filter indicator, which will show when the filters become obstructed.
Although this should not be relied on as the only determinant for replacing filters. A maladjusted
filter differential pressure switch may not give a proper indication of a clogged filter.
To check the filter differential pressure switch for proper adjustment, temporarily cover about
75% of the return air opening using heavy cardboard or similar material. The alarm should
energize when 75% of the air is blocked, simulating dirty filters. If the alarm energizes prematurely
or does not energize at all, the pressure switch should be adjusted. Doors must remain closed
when determining if an adjustment is necessary.
Clogged filter can restrict air flow and create problems such as coil icing or poor air distribution.
Liquid Line Filter Drier
The filter drier core normally does not need to be changed. However, after intervention at any
device in the refrigerant line, such as copper lines and fittings, compressor, condenser, valves, or
coils, it is important to replace the filter drier core. Startup the machine, operate for several
minutes, stop the machine, and replace the filter drier core.
4.6. Drives (sheaves and belts)
V-belt drives need periodic inspection and occasional belt replacement. When inspecting drives,
look for dirt buildup, burrs or obstructions which can cause premature belt or drive replacement.
If burrs are found, use fine emery cloth or a stone to remove the burr. Be careful that dust does
not enter the bearings.
Check the sheaves for wear. Excessive slippage of belts on sheaves can cause wear and vibration.
Replace worn sheaves with new ones. Carefully align sheaves to avoid premature sheave failure.
Observe belts for wear. If fraying or other wear is observed to be mostly on one side of the belts,
the drives may be misaligned. Reinstall the drivers according to instructions below. Never use belt
dressing on any belts.
When replacing belts, replace the entire set. After initial replacement and tensioning, recheck belt
tension after a few days to adjust belt tension again. New belts require a break-in period of
operation.
Refer to technical bulletin TB-33 for belt tension adjustment and sheave alignment.