System Maintenance; General; Electrical Terminals - Daikin WGZ030DW Operating And Maintenance Manual

System Maintenance

General

To provide smooth operation at peak capacity and to avoid damage to package components, a program of
periodic inspections should be set up and followed. The following items are intended as a guide to be
used during inspection and must be combined with sound refrigeration and electrical practices to provide
trouble-free performance.
The liquid line sight glass/moisture indicator on all circuits must be checked to be sure that the glass is
full and clear and that the moisture indicator indicates a dry condition. If the indicator shows that a wet
condition exists or if bubbles show in the glass, even with a full refrigerant charge, the filter-drier element
must be changed.
Water supplies in some areas can tend to foul the water-cooled condenser to the point where cleaning is
necessary. The fouled condenser will be indicated by an abnormally high condenser approach temperature
(saturated discharge temperature minus leaving condenser water temperature) and can result in nuisance
trip-outs. To clean the condenser, mechanical cleaning or a chemical descaling solution should be used
according to the manufacturer's directions.
Remote air-cooled condensers require periodic cleaning of the finned surface of the condenser coil.
Cleaning can be accomplished by using a cold water spray, brushing, vacuuming, or high-pressure air. No
tools should be used that could damage the coil tubes or fins.
The compressor oil level must be checked periodically to be sure that the level is at the center of the oil
sightglass located in the compressor's equalizing line or on the compressor itself. Low oil level can cause
inadequate lubrication and if oil must be added, use oils referred to in the following "Compressor
Lubrication" section.
A pressure tap has been provided on the liquid line downstream of the filter-drier and solenoid valve but
before the expansion valve. An accurate subcooled liquid pressure and temperature can be taken here. The
pressure read here could also provide an indication of excessive pressure drop through the filter-drier and
solenoid valve due to a clogging filter-drier. Note: A normal pressure drop through the solenoid valve is
approximately 3 psig (20.7 kPa) at full load conditions.
Warranty may be affected if wiring is not in accordance with specifications. Before replacing
blown fuse or restarting compressor, the trouble must be found and corrected. It is important to
have a qualified control panel electrician service this panel. Unqualified tampering with the
controls can cause serious damage to equipment and void the warranty.
The panel is always energized to ground even when the system switch is off. To de-energize the
complete panel including crankcase heaters, pull the main unit disconnect. Failure to do so can

Electrical Terminals

To avoid injury from electric shock hazard, turn off all power and perform lockout and tag-out of
source before continuing with the following service. Note that the unit might be powered from
All power electrical terminals should be re-tightened every six months, as they tend to loosen due to
normal heating and cooling of the wire.
OMM 1130-2
CAUTION
!
DANGER
!
result in severe personal injury or death.
WARNING
!
multiple sources.
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