Lennox CHA16, Руководство по обслуживанию

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LIFTING BRACKETS (4)
TWO EACH SIDE
FIGURE 9
LIFTING BRACKETS
SIDE VIEW
Page 16
FIGURE 8
CHA16-2553, 2753, 3003 UNIT CONTROL BOX
F10
TB13
K3
S42
F16
K10 K68 K2 K1
S3
A9
A10
T1
T18
A11
TB17
PILOT RELAY BOARD
A11
INDOOR BLOWER
CONTACTOR K3
CONTACTOR
TRANSFORMER T18
CONTROL
TRANSFORMER T1
TERMINAL
STRIP TB17
COMPRESSOR
PROTECTOR A9
COMPRESSOR
PROTECTOR
A10
POWER DISTRIBUTION
BLOCK TB13
OUTDOOR FAN
MOTOR FUSE F10
INDOOR BLOWER
MOTOR FUSE F16
INDOOR
BLOWER MOTOR
OVERLOAD
RELAY S42
2nd STAGE
CONDENSER FAN
CONTACTOR K68
2nd STAGE
COMPRESSOR CON
TACTOR K2
1st STAGE
COMPRESSOR
CONTACTOR K1
1st STAGE
CONDENSER FAN
CONTACTOR K10
COMPRESSOR
MONITOR/
LOW TEMP LIMIT
S3
FUSE F1
FUSE F18
I-APPLICATION
CHA16 15 ton units are available in a single cabinet size
(refer to the Engineering Handbook for more specific ap
plication data). All units are factory equipped with the hard
ware required for installing Lennox optional thermostat
control systems. Lennox' optional thermostat control sys
tems are the same controls, harnesses, and harness
plugs used in all previously released CHA16 commercial
units. For example, a Honeywell W973 control will plug in
to a CHA16-1853 as easily as it will plug in to a CHA16-411
(and no field wiring is required for either).
II-UNIT COMPONENTS
An overview of CHA16 series unit components are shown
in figures 1, 2, 3 and 4.
A-Lifting Brackets
Each unit is equipped with factory
installed lifting brackets as shown
in figure 9. Brackets are used for
lifting the unit during installation or
when servicing. Lifting lugs can be
removed from the unit and reused.
If unit must be lifted for service, use
only lifting brackets to lift unit.
B-Control Box Components
CHA16 control box is shown in figures 5, 6, 7 and 8. The
control box is located in the upper portion of the compressor
compartment behind the compressor compartment access
panel. In larger units, a hinged door with magnetic latch lo
cated behind the compressor access panel, provides access
to control components.
1-Power Distribution Terminal Block TB13
(1853, 2553, 2753, 3003)3003)
All Larger CHA16 units use a power distribution terminal
block to provide a line voltage electrical connection be
tween the control box components and the power entry
area in the heating compartment. Line voltage cables con
nect TB13 with the unit terminal block TB2 located in the
heating compartment.
2-Terminal Block TB17 (2553, 2753, 3003)
TB17 is a low voltage terminal block located in the control
box of 18.5 ton and larger units. The terminal strip is de
signed for diagnostic troubleshooting and test running the
unit from the control box area. TB17 terminals are desig
nated as shown in table 1.
TABLE 1
TERMINAL
NUMBER
TB17 TERMINAL DESIGNATIONS
1 24VAC Power
2 First stage thermostat Y1
3
Input to pilot relay K66
(24VAC applied here will energize 1st stage cooling)
4 Second stage thermostat Y2
5
Input to pilot relay K67
(24VAC applied here will energize 2nd stage cooling)
6 24VAC common
3-Transformer T1 (all units)
All CHA16 series units use a single line voltage to 24VAC
transformer mounted in the control box. The transformer
supplies power to control circuits in the unit (except the
heating section). Transformer is rated at 70VA. 208/230
(P) voltage transformers use two primary voltage taps as
shown in figure 10.