Millennium Enterprises Z42 Air Conditioner User Manual


 
882108-YIM-B-1012
66 Johnson Controls Unitary Products
Example: By actual measurement, it takes 7 seconds for the
hand on the one cubic foot dial to make a revolution with just
a 570,000 Btuh furnace running. Read across to the column
in Table 24, headed 1 Cubic Foot where you will determine
that 525 cubic feet of gas per hour are consumed by the fur-
nace at that rate. Multiply 525 x 1050 (the Btu rating of the
gas obtained from the local gas company). The result of
551,000 Btuh is within 5% of the 570,000 Btuh rating of the
furnace.
ELECTRIC HEATING
The electric furnace is operational as shipped from the fac-
tory and does not receive any field adjustments.
COOLING OPERATING INSTRUCTIONS
COMPRESSOR
Compressors are factory mounted ready for operation (See
page 59 Compressor Rotation).
INTERNAL WIRING
Check all electrical connections in the unit control box;
tighten as required.
CONDENSER FANS
Check for proper condenser fan rotation; clockwise facing the
air discharge. If condenser fans are rotating backwards, line
voltage to unit single point power connection is misphased
(See page 59 Compressor Rotation).
SERVICE
REFRIGERATION SYSTEM
CHARGE: Each system is fully factory charged with R-410A.
The correct charge appears on the unit nameplate.
Thermal Expansion Valves: The 30 ton unit has 3 and the 40
ton unit has 4 independent refrigeration systems. These
TXVs are set to maintain 15°F superheat leaving the evapo-
rator coil. The superheat on each valve is adjustable, how-
ever, adjustments should only be made if absolutely
necessary.
FILTER DRIER: Each system is equipped with a filter drier.
The drier should be replaced whenever moisture is indicated
in the system.
COMPRESSORS
Each compressor is inherently protected from over current
and over temperature. High and low pressure switches are
installed on the discharge and suction lines respectively for
high and low pressure protection. Scroll compressors operate
in only one direction. If the compressor is experiencing low
amperage draw, similar discharge and suction pressure or
increased noise level, it is operating in reverse. Switch two
line voltage connections to correct (See Compressor Rotation
page 59).
MOTORS
INDOOR BLOWER MOTORS
All indoor blower motors are non-inherently protected three
phase motors. Overcurrent protection is provided by a man-
ual reset starter/overload relay and short circuit protection is
provided by fuses. Where there is a supply fan VFD, an auxil-
iary contact provides the overcurrent indication to the Sim-
plicity® control.
POWER EXHAUST OR RETURN AIR FAN MOTORS
All motors are non-inherently protected three phase motors.
Overcurrent protection is provided by a manual reset
starter/overload relay and short circuit protection is provided
by fuses.
CONDENSER FAN MOTORS
All condenser fan motors are inherently protected three
phase motors. Short circuit protection is provided by fuses.
DRAFT MOTOR (GAS FURNACE)
All draft motors are line voltage, inherently protected, single
phase PSC motors. Short circuit protection is provided by
fuses.
TABLE 45: GAS RATE - CUBIC FEET PER HOUR
Seconds for One
Rev.
Size of Test Dial
1/2 cu. Ft. 1 cu. Ft.
2 900 1800
4 450 900
6 300 600
8 225 450
10 180 360
FIGURE 26 - TYPICAL FLAME APPEARANCE
G A S
S U P P L Y
P I P E
B U R N E R
B U R N E R B R A C K E T
I G N I T O R
B U R N E R F L A M E
( B L U E O N L Y )
H E A T E X C H A N G E R T U B E