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Actuators
In the
AC.T.C
submenu, it will be possible to control and cali
-
brate actuators. Calibration is a mode in which the actuator
moves from 0% to the point at which the actuator stalls, and it
will then use this angular travel range as its “control angle.” It
will also be possible to view the “control angle” adopted by the
actuator after a calibration.
Within this submenu, the user may calibrate and control the 3
economizer actuators (2 outdoor air and 1 return air), hydronic/
steam or humidifier actuators.
NOTE: Once a calibration has been started, the user cannot
exit test mode or select any other test mode operation until
complete.
Humidi-MiZer
®
System
In the Humidi-MiZer (
HMZR
) submenu, it will be possible to
control and calibrate the Humidi-MiZer modulating valves (gas
bypass and condenser) while the unit’s compressors are OFF.
Calibration is a mode in which the unit software will first over-
drive each valve completely shut and establish the “zero” open
position. The controller then keeps track of the valve’s position
for normal operation. During this calibration phase, a light ratch
-
eting sound may be heard and will serve as proof of valve opera
-
tion and closure. Note that the calibration feature in Service Test
is only provided as an additional troubleshooting tool. This is to
ensure that the valve will automatically go through the calibra
-
tion process anytime the unit is powered down, unit power is cy
-
cled, or there is a loss of communication between the EXV board
and the valve. There should be no need to manually calibrate the
valves under normal circumstances.
This submenu also allows manual manipulation of RHV (re
-
heat 3-way valve), the bypass valve, and condenser valve. With
the compressors and outdoor fans off, the user should hear a
light ratcheting sound during movement of the 2 modulating
valves. The sound can serve as proof of valve operation.
Service Test
HMZR
RHV (Humidi-MiZer 3-Way Valve)
On Humidi-MiZer equipped units, this item allows the user to
switch the reheat valve from ON to OFF or OFF to ON when
compressors are in the OFF position. When
RHV
is switched
to the ON position, the 3-way valve will be energized. When
RHV
is switched to the OFF position, the 3-way valve will be
de-energized. To exercise this valve with a Circuit B compres
-
sor commanded ON, go to (
Service Test
COOL
RHV
). To
view the actual valve position at any time, the user can use the
Outputs menu (
Outputs
COOL
RHV
).
Service Test
HMZR
C.EXV (HMV-1: Condenser EXV
Position)
On Humidi-MiZer equipped units, this item allows the user to
exercise the valve that controls flow to the Circuit B condenser.
The valve default position is 100% (completely open). The
user will be able to adjust the valve from 0 to 100% through
this function. As confirmation that the valve is operational, the
user should hear a light ratcheting sound as the valve opens and
closes. Note that this function is only operational when Circuit
B compressors are OFF. To exercise this valve with a Circuit B
compressor commanded ON, go to (
Service Test
COOL
C.EXV
). To view the actual valve position at any time, the
user can use the Outputs menu (
Outputs
COOL
C.EXV
).
Service Test
HMZR
B.EXV (HMV-2: Bypass EXV Position)
On Humidi-MiZer equipped units, this item allows the user to
exercise the valve that controls discharge gas bypass around the
Circuit B condenser. The valve default position is 0% (complete
-
ly closed). The user will be able to adjust the valve from 0 to
100% through this function. As confirmation that the valve is
operational, the user should hear a light ratcheting sound as the
valve opens and closes. Note that this function is only operation
-
al when Circuit B compressors are OFF. To exercise this valve
when a Circuit B compressor is ON, go to (
Service
Test
COOL
B.EXV
). To view the actual valve position at any
time, the user can use the Outputs menu (
Out
-
puts
COOL
B.EXV
).
Service Test
HMZR
C.CAL (Condenser EXV Calibrate)
On Humidi-MiZer configured units, this item allows the user
to calibrate the valve that controls flow to the Circuit B con
-
denser. Switching C.CAL to ON will instruct the unit software
to over-drive the valve in the closing direction. This is to en
-
sure that the valve is completely shut and to establish the “ze
-
ro” open position. The controller then keeps track of the
valve’s position for normal operation. During this calibration
phase, a light ratcheting sound may be heard and will serve as
proof of valve operation and closure. Note that the calibration
feature in Service Test is only provided as an additional trou
-
bleshooting tool. The valves will automatically go through the
calibration process anytime the unit is powered down, unit
power is cycled, or there is a loss of communication between
the EXV board and the valve. There should be no need to man
-
ually calibrate the valves under normal circumstances.
Service Test
HMZR
B.CAL (Bypass EXV Calibrate)
On Humidi-MiZer configured units, this item allows the user to
calibrate the valve that controls discharge gas bypass around the
Circuit B condenser. Switching
B.CAL
to ON will instruct the
unit software to over-drive the valve in the closing direction.
This is to assure that the valve is completely shut and to establish
the “zero” open position. The controller then keeps track of the
valve’s position for normal operation. During this calibration
phase, a light ratcheting sound may be heard and will serve as
proof of valve operation and closure. Note that the calibration
feature in Service Test is only provided as an additional trouble
-
shooting tool. The valves will automatically go through the cali
-
bration process anytime the unit is powered down, unit power is
cycled, or there is a loss of communication between the EXV
board and the valve. There should be no need to manually cali
-
brate the valves under normal circumstances.
Cooling
The cooling submenu offers many different service tests.
•
Service Test
COOL
E.POS
(Econo Damper Command
Pos). It is possible to manually move the actuator during
the cooling test mode at all times, regardless if economizer
cooling is suitable or not.
•
Service Test
COOL
SP.SP
(Static Pressure Set Point).
Upon entering the cooling submenu, the static pressure
control item will default to the unit’s static pressure set
point. Thereafter, as mechanical cooling commences and
the fan starts, the static pressure can be manually adjusted
during the cool mode without affecting the configured set
point for normal runtime operation. By adjusting the static
pressure set point, the user can increase or decrease the
supply airflow. Do not use a static pressure that will ex
-
ceed the system limits.
•
Service Test
COOL
CL.ST
(Requested Cool Stage). If
this item is set to a non-zero value, the current assigned com
-
pression stage for this unit will be selected and enacted.
Thereafter, the individual compressor will be “read-only” and
reflect the current staging state. In addition, this item will au
-
tomatically clamp the cooling stages to its pre-configured
maximum.
• Manual relay control of individual compressors. If the cool
-
ing stage pattern request is set to zero, the user will have the
ability to manually control compressors. If the user energiz
-
es mechanical cooling, the supply fan and the outdoor fans
will be started automatically. During mechanical cooling,
the unit will protect itself. Compressor diagnostics are ac
-
tive, monitoring for high discharge pressure, low suction
pressure, etc. The user can also turn the minimum load valve
on and off and set the digital scroll capacity (on units
equipped with this device).
Summary of Contents for WeatherExpert 48N2
Page 135: ...135 Fig 18 48 50N Typical Power Schematic Nominal 075 Ton Unit Shown ...
Page 136: ...136 Fig 19 48 50N Typical Power Schematic Nominal Ton 90 150 Units Shown ...
Page 137: ...137 Fig 20 48 50N Main Base Board Input Output Connections ...
Page 138: ...138 Fig 21 48 50N RXB EXB CEM Input Output Connections a48 9307 ...
Page 139: ...139 Fig 22 48 50N EXV SCB Input Output Connections a48 9308 ...
Page 140: ...140 Fig 23 48N Typical Modulating Gas Heat Unit Control Wiring ...
Page 141: ...141 Fig 24 50N Typical Electric Heat Unit Control Wiring ...
Page 144: ...144 Fig 27 48N Typical Gas Heat Section Wiring Nominal Ton 120 to 150 Units ...
Page 145: ...145 Fig 28 48 50N Typical Power Component Control Wiring 460 v ...
Page 146: ...146 Fig 29 48 50N Component Control Wiring 575 v Nominal Ton 075 to 150 Units ...
Page 147: ...147 Fig 30 48 50N Component Arrangement Power Box ...
Page 148: ...148 Fig 31 48 50N Component Arrangement Control Box ...
Page 240: ...240 APPENDIX D VFD INFORMATION CONT Fig G VFD Bypass Wiring Diagram WHEN USED ...