Dunham-Bush ACXi 165-5SP-LN, Инструкция по установке, эксплуатации и обслуживанию

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5.0 MAINTENANCE
5.1 GENERAL
As with all mechanical equipment, a program of
regular inspection, cleaning and preventive
maintenance by trained personnel will contribute
greatly to the long satisfactory service life of this
product.
5.2 PERIODIC INSPECTION
Read essential temperatures and pressures
periodically to see that they indicate normal
operation. It is a good idea to record these
readings on a log sheet. If any abnormal
operation is observed, try to remedy it. See
Trouble Shooting Guide Section.
5.3 MONTHLY INSPECTION
Remote dirt and debris from condenser coil. Shut
unit down, open main disconnect, inspect control
panel, checking for loose wires, burned contacts,
signs of overheated wires, etc. Restart unit and
check performance of controls. Check sight
glasses for proper refrigerant charge, see
charging.
5.4 VESSEL MAINTENANCE
5.4.1 GENERAL
The efficient performance of the
evaporator and condenser heat transfer
surfaces is essential for efficient
performance of your packaged water
cooling machine. If these surfaces
accumulate a film of dirt, scale or slime,
their performance efficiency will
degrade substantially. The refrigerant
side of heat transfer surfaces does not
foul since refrigerant is a good solvent
and it is in a closed, filtered cycle. Water
side surfaces can foul from the water
system. A program of water treatment
can slow the rate of fouling on heat
transfer surfaces, but not eliminate it.
5.4.2 WATER SIDE CLEANING OF
EVAPORATOR
The effects of fouling of the evaporator
heat transfer surfaces can be detected by
recording full load performance data on
the log sheet. The best measure of
performance of evaporator is approach,
which is the difference between leaving
water temperature and saturated
refrigerant temperature at the pressure in
the vessel. At full load, read evaporator
pressure and leaving chilled water
temperature on the computer. Then use
Table 5.4.2 to find saturated temperature
in evaporator. Then calculate approaches
as follows:
Evaporator Approach = T lvg chilled
water - T sat Evaporator
If the approach increases by more than
2°F above the approach recorded at clean
conditions, the tubes should be cleaned.
It is generally advisable to clean the
water side surfaces at least annually and
more often if severely foul water is used.
In chemical cleaning, a caustic solution
is pumped through the heat exchanger,
which attacks dirt, slime and mineral
deposits and flushes then away.
Chemicals can be recommended by
water treatment specialists, but it is
important to rinse the system thoroughly
after cleaning to remove the chemicals
before they attack the metal surfaces.
5.5 AIR COOLED
CONDENSER CLEANING
The face of the condenser should be cleaned at
least once month during operation. If conditions
are bad and condensers pick up dirt very quickly,
it is suggested that they can be cleaned more
frequently. If the condenser is allowed to get too
dirty, the unit will run at high head pressure and
will not give satisfactory performance.
Dirty coils can be cleaned using a soft brush or
by flushing with cool water or commercially
available coil cleaners. DO NOT USE HOT
WATER OR STEAM. To do so will cause
excessive pressure in the system. The face of the
condenser should be cleaned at the beginning of
the season and periodically thereafter if
conditions require.
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