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60
Heating Control
The N Series
Comfort
Link controls offers control for 6 different
types of heating systems to satisfy general space heating re
-
quirements: 2-stage gas heat, 2-stage electric heat, SCR (mod
-
ulating) electric heat, steam heat, modulating gas heat, and hy
-
dronic heat. Heating control also provides tempering and re
-
heat functions. These functions are discussed in separate
sections. Reheat is discussed under Dehumidification and Re
-
heat section on page 89.
Variable air volume (VAV) type applications (
C.TYP
= 1 or 2)
require that the space terminal positions be commanded to
open to minimum heating positions when gas or electric heat
systems are active, to provide for the unit heating system’s
Minimum Heating Airflow rate.
Also, for VAV applications, the heat interlock relay (HIR)
function provides the switching of a control signal intended for
use by the VAV terminals. This signal must be used to
command the terminals to open to their Heating Open posi
-
tions. The HIR is energized whenever the Heating mode is ac
-
tive, an IAQ pre-occupied force is active, or if fire smoke
modes, pressurization, or smoke purge modes are active.
Hydronic and steam heating applications that use the unit’s
control require the installation of a communicating actuator on
the hydronic heating coil’s control valve. This actuator (with or
without matching control valve) may be separately shipped for
field installation.
All heating systems are available as factory-installed options.
The hydronic or steam heating coil may also be field-supplied
and field-installed; the actuator is still required if unit control
will be used to manage this heating sequence.
POST FILTER APPLICATION
Gas heat controls also use an airflow switch when post filter
option is installed in unit. Lack of airflow will prevent gas heat
from operating.
Electric heat controls add filter temperature switches at the post
filters. The filter temperature switches will prevent electric heat
from operating when high temperatures are experienced.
SETTING UP THE SYSTEM
The essential heating configurations located at the local display
under
Configuration
HEAT
.
See Table 34.
Table 34 —
Heating Configuration
*Some defaults are model number dependent.
ITEM
EXPANSION
RANGE
UNITS
CCN POINT
DEFAULT
HEAT
HEATING CONFIGURATION
HT.CF
Heating Control Type
0 to 5
HEATTYPE
0*
HT.SP
Heating Supply Air Setpt
65 to 120
dF
SASPHEAT
85
OC.EN
Occupied Heating Enabled
No/Yes
HTOCCENA
No
LAT.M
MBB Sensor Heat Relocate
No/Yes
HTLATMON
No
SG.CF
STAGED HEAT CONFIGS
HT.ST
Staged Heat Type
0 to 3
HTSTGTYP
0*
CAP.M
Max Cap Change per Cycle
5 to 45
HTCAPMAX
45*
M.R.DB
St.Ht DB min.dF/PID Rate
0 to 5
HT_MR_DB
0.5
S.G.DB
St.Heat Temp. Dead Band
0 to 5
^F
HT_SG_DB
2
RISE
Heat Rise dF/sec Clamp
0.05 to 0.2
HTSGRISE
0.06
LAT.L
LAT Limit Config
0 to 20
^F
HTLATLIM
10
LIM.M
Limit Switch Monitoring?
No/Yes
HTLIMMON
Yes
SW.H.T
Limit Switch High Temp
80 to 210
dF
HT_LIMHI
170*
SW.L.T
Limit Switch Low Temp
80 to 210
dF
HT_LIMLO
160*
HT.P
Heat Control Prop. Gain
0 to 1.5
HT_PGAIN
1
HT.D
Heat Control Derv. Gain
0 to 1.5
HT_DGAIN
1
HT.TM
Heat PID Rate Config
30 to 300
sec
HTSGPIDR
90*
HH.CF
HYDRONIC HEAT CONFIGS
HW.P
Hydronic Ctl.Prop. Gain
0 to 1.5
HW_PGAIN
1
HW.I
Hydronic Ctl.Integ. Gain
0 to 1.5
HW_IGAIN
1
HW.D
Hydronic Ctl.Derv. Gain
0 to 1.5
HW_DGAIN
1
HW.TM
Hydronic PID Rate Config
15 to 300
sec
HOTWPIDR
90
ACT.C
HYDR.HEAT ACTUATOR CFGS.
SN.1.1
Hydronic Ht.Serial Num.1
0 to 9999
HTC1_SN1
0
SN.1.2
Hydronic Ht.Serial Num.2
0 to 6
HTC1_SN2
0
SN.1.3
Hydronic Ht.Serial Num.3
0 to 9999
HTC1_SN3
0
SN.1.4
Hydronic Ht.Serial Num.4
0 to 254
HTC1_SN4
0
C.A.L1
Hydr.Ht.Ctl.Ang Lo Limit
0 to 90
HTC1CALM
0
SN.2.1
Humd/HTC2 Ser Num 1
0 to 9999
HTC2_SN1
0
SN.2.2
Humd/HTC2 Ser Num 2
0 to 6
HTC2_SN2
0
SN.2.3
Humd/HTC2 Ser Num 3
0 to 9999
HTC2_SN3
0
SN.2.4
Humd/HTC2 Ser Num 4
0 to 254
HTC2_SN4
0
C.A.L2
Humd/HTC2 Ctl Ang Lo Lim
0 to 90
HTC2CALM
0
SN.3.1
HTC3 Serial Number 1
0 to 9999
HTC3_SN1
0
SN.3.2
HTC3 Serial Number 2
0 to 6
HTC3_SN2
0
SN.3.3
HTC3 Serial Number 3
0 to 9999
HTC3_SN3
0
SN.3.4
HTC3 Serial Number 4
0 to 254
HTC3_SN4
0
C.A.L3
HTC3 Ctrl Angle Lo Limit
0 to 90
HTC3CALM
0
SN.4.1
HTC4 Serial Number 1
0 to 9999
HTC4_SN1
0
SN.4.2
HTC4 Serial Number 2
0 to 6
HTC4_SN2
0
SN.4.3
HTC4 Serial Number 3
0 to 9999
HTC4_SN3
0
SN.4.4
HTC4 Serial Number 4
0 to 254
HTC4_SN4
0
C.A.L4
HTC4 Ctrl Angle Lo Limit
0 to 90
HTC4CALM
0
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 ...