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36
Table 43 — Unit Configuration
Discharge Pressure Transducers (
DP.XR
) — This configuration
configures the unit for use with discharge pressure transducers.
Suction Pressure Transducer Type (
SP.XR
) — This configu-
ration specifies the type of suction pressure transducer that is
being used. Set
SP.XR
to 0 for support of a pressure transducer
with a range of 0 to 135 psig. Set
SP.XR
to 1 for support of a
pressure transducer with a range of 0 to 200 psig.
MAT Calc Config (
MAT.S
) — This configuration gives the
user two options in the processing of the mixed-air temperature
(MAT) calculation:
•
MAT.S
= 0
There will be no MAT calculation.
•
MAT.S
= 1
The control will attempt to learn MAT over time. Any time
the system is in a vent mode and the economizer stays at a
particular position for long enough, MAT = EDT. Using
this, the control has an internal table whereby it can more
closely determine the true MAT value.
•
MAT.S
= 2
The control will not attempt to learn MAT over time.
To calculate MAT linearly, the user should reset the MAT
table entries by setting
MAT.R
to YES. Then set
MAT.S
= 2
.
The control will calculate MAT based on the position of the
economizer, outside air temperature, and return air tempera-
ture.
To freeze the MAT table entries, let the unit run with
MAT.S
= 1
. Once sufficient data has been collected, change
MAT.S
= 2
. Do not reset the MAT table.
Reset MAT Table Entries? (
MAT.R
) — This configuration
allows the user to reset the internally stored MAT learned con-
figuration data back to the default values. The defaults are set
to a linear relationship between the economizer damper posi-
tion and OAT and RAT in the calculation of MAT.
MAT Outside Air Position Default (
MAT.D
) — This config-
uration is used to calculate MAT when the economizer option
is disabled. The configuration is adjustable from 0 to 100%
outside air. This defines the fixed ventilation position that will
be used to correctly calculate MAT.
Altitude……..In Feet: (
ALTI
) — As the control does not in-
clude a barometric pressure sensor to define the calculation of
enthalpy and cfm, the control does include an altitude parame-
ter which will serve to set up a default barometric pressure for
use with calculations. The effect of barometric pressure in
these calculations is not great, but could have an effect depend-
ing on the installed elevation of the unit. If the rooftop is
installed at a particularly high altitude and enthalpy or cfm are
being calculated, set this configuration to the current elevation
of the installed rooftop.
Start Up Delay Time (
DLAY
) — This option inhibits the unit
from operating after a power reset. The configuration may be
adjusted from 0 to 900 seconds of delay.
TSTAT — Both Heat and Cool (
STAT
) — This option, if en-
abled, allows both heating and cooling requests to be made. If
the unit is configured for staged gas heat, and if a cooling
request is initiated (Y1 or Y2), then W1 initiates reheat and W2
initiates dehumidification.
Space Temp Sensor (
SPT.S
) — If a space temperature sensor
is installed (T55/T56), enable this configuration.
Space Temp Offset Sensor (
SP.O.S
) — If a T56 sensor is
installed with the space temperature offset slider, enable this
configuration.
Space Temp Offset Range (
SP.O.R
) — If a space tempera-
ture offset sensor is installed, it is possible to configure the
range of the slider by adjusting this range configuration.
Return RH Sensor (
RRH.S
) — If a return air relative humidi-
ty sensor is installed, enable this configuration.
Filter Status Switch Enabled? (
FLT.S
) — If a filter status
switch is installed, enable this configuration to begin the moni-
toring of the filter status input (
Inputs
→
GEN.I
→
FLT.S
). See
the Dirty Filter Switch section for more details on installation
and operation.
Cooling Control —
When mechanical cooling is required,
the A Series
Comfort
Link™ control has the capability to con-
trol the staging of the compressors in several different ways.
Three scroll compressors are used on sizes 020 to 027 and four
on sizes 030 to 060. In addition, the
Comfort
Link control sup-
ports the use of an optional minimum load hot gas bypass
valve (MLV) that is directly controlled by the
Comfort
Link
control, and provides an additional stage of capacity as well as
low load coil freeze protection. The control also integrates the
use of an economizer with the use of mechanical cooling to
allow for the greatest use of free cooling. When both mechani-
cal cooling and the economizer are being used, the control will
use the economizer to provide better temperature control and
limit the cycling of the compressors. The control also checks
on various other operation parameters in the units to make sure
that safeties are not exceeded and the compressors are reliably
operated.
ITEM
EXPANSION
RANGE
UNITS
CCN POINT
DEFAULTS
UNIT
UNIT CONFIGURATION
C.TYP
Machine Control Type
1 - 6
CTRLTYPE
4
CV.FN
Fan Mode (0=Auto, 1=Cont)
0 - 1
FAN_MODE
1
RM.CF
Remote Switch Config
0 - 3
RMTINCFG
0
CEM
CEM Module Installed
Yes/No
CEM_BRD
No
TCS.C
Temp.Cmp.Strt.Cool Factr
0 - 60
min
TCSTCOOL
0
TCS.H
Temp.Cmp.Strt.Heat Factr
0 - 60
min
TCSTHEAT
0
SFS.S
Fan Fail Shuts Down Unit
Yes/No
SFS_SHUT
No
SFS.M
Fan Stat Monitoring Type
0 - 2
SFS_MON
0
VAV.S
VAV Unocc.Fan Retry Time
0 - 720
min
SAMPMINS
50
SIZE
Unit Size (20-60)
20 - 60
UNITSIZE
20
DP.XR
Discharge Press. Transducers
Yes/No
DP_TRANS
No
SP.XR
Suct. Pres. Trans. Type
0 - 1
SPXRTYPE
0
MAT.S
MAT Calc Config
0 - 2
MAT_SEL
1
MAT.R
Reset MAT Table Entries?
Yes/No
MATRESET
No
MAT.D
MAT Outside Air Default
0-100
%
MATOADOS
20
ALTI
Altitude……..in feet:
0 - 60000
ALTITUDE
0
DLAY
Startup Delay Time
0 - 900
sec
DELAY
0
STAT
TSTAT-Both Heat and Cool
Yes/No
TSTATALL
No
SENS
INPUT SENSOR CONFIG
SPT.S
Space Temp Sensor
Enable/Disable
SPTSENS
Disable
SP.O.S
Space Temp Offset Sensor
Enable/Disable
SPTOSENS
Disable
SP.O.R
Space Temp Offset Range
1 - 10
SPTO_RNG
5
RRH.S
Return Air RH Sensor
Enable/Disable
RARHSENS
Disable
FLT.S
Filter Stat.Sw.Enabled ?
Enable/Disable
FLTS_ENA
Disable
Summary of Contents for WEATHERMAKER 48AJ020
Page 95: ...95 Fig 13 Typical Main Control Box Wiring Schematic A48 7787 ...
Page 96: ...96 TO NEXT PAGE Fig 14 Auxiliary Control Box Wiring Schematic A48 7294 ...
Page 98: ...98 Fig 15 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown A48 6866 ...
Page 102: ...102 TO NEXT PAGE Fig 18 Typical Power Schematic Size 051 and 060 Units Shown A48 7298 ...
Page 104: ...104 Fig 19 Controls Option Wiring Schematic A48 7810 ...
Page 105: ...105 Fig 20 Small Chassis Component Location Size 020 035 Units A48 7301 ...
Page 106: ...106 Fig 21 Large Chassis Component Locations Size 036 060 Units A48 7302 ...