Koldwave KWV-20, Инструкция по установке, эксплуатации и обслуживанию

Страница: 7 / 12

Subject to change without notice.
7
KWV-20G*ATA**
REV — 02/26/20
UNIT COMPONENTS
Optional Deflection Registers
The supply grilles are divided into 2 rows of
manually adjustable louvers.
The horizontal louvers are in the front row. These
are individually adjusted by hand.
The vertical louvers are the second or back row.
Each section has a louver adjustment tab. The
tab will adjust the vertical louvers as a section and
can be moved with your finger.
Optional Hour Meter
The unit may be equipped with an optional
hour meter. This meter indicates the cumulative
operating time of the system.
Sight Glass
Each refrigerant circuit has a sight glass to
determine that a liquid seal of refrigerant exists
going to the expansion valve.
The sight glass also has a moisture indicator to
detect the presence of moisture in the refrigerant.
The indicator is yellow if moisture is present and
green in color if there is no moisture.
If bubbles appear in the sight glass, the system is
either undercharged with refrigerant or there may
be a restriction in the liquid line upstream of the
sight glass.
NOTE: Bubbles will occur for a minute or two
when the compressor system starts.
Bubbles will also be present during low
ambient operation or on the 20-ton unit
circuit 1 when the hot gas bypass is
activated. Do not add charge to overcome
bubbles for these reasons.
Access Fittings
Each refrigerant circuit is provided with Schrader
type access fittings. These can be used to adjust
the refrigerant charge if necessary.
Air Flow
The units are provided with an air proving switch.
If air flow is not detected, the unit will not allow
the cooling circuit to function. This protects in the
case of a motor or belt failure.
Pressure Switches
Each refrigerant circuit is provided with a High
and a Low pressure switch. These are automatic
reset type.
These units contain lockout relays that activate
when the pressure switch(s) open the circuit. The
main power to the unit must be switched Off and
then On to reset the lock out relays
CAUTION: Unit power should be turned off
when doing any work on the unit
when one or both of the pres-
sure switches has been opened .
Unit may start when the pressure
switches automatically reset, thus
causing a hazard to the service
personnel .
Hot Gas Bypass
20-ton units have a Hot Gas Bypass valve on
System 1. This valve helps keep the system
running when the space load drops. It functions
by artificially loading the evaporator with some hot
discharge gas from the compressor into the inlet
of the evaporator.
MAINTENANCE
Bearings
Motor and Blower bearings are permanently
lubricated and require no maintenance.
Belts
The condenser and evaporator blowers are belt
driven and are provided with adjustable sheaves
to change the speed. The drive belts should be
examined periodically for wear and for correct
tension. If the belts are too tight it can cause