67
Table 52 — Modulating Gas Heat Control Steps (
HT.ST
= 5)
* ON when
Outputs
HEAT
H1.CP
> 54%, OFF when
Outputs
HEAT
H1.CP
< 46%.
Table 53 — SCR Electric Heat
Table 54 — SCR Electric Heat Control Steps
(HT.ST=6)
Table 55 — SCR Electric Heat Control Steps
(HT.ST=7)
Table 56 — SCR Electric Heat Control Steps
(HT.ST=8)
If the Limit Switch Monitoring configuration parameter
(
LIM.M
) is set to YES, all the modes will be monitored. If set
to NO, then only LAT Cutoff mode and Capacity Clamp mode
for
RISE
will be monitored.
If
S.G.LS
rises above
SW.L.T
or if (LAT – LAT last time
through the capacity calculation) is greater than (
RISE
) de-
grees F per second, the control will not allow the capacity rou-
tine to add stages and will turn on the Capacity Clamp mode.
If
S.G.LS
rises above
SW.H.T,
the control will run the capacity
routine immediately and drop all heat stages and will turn on
the Limiting mode.
If
S.G.LS
falls below
SW.L.T,
the control will turn off both Ca-
pacity Clamp mode and Limiting mode with one exception. If
(LAT – LAT last time through the capacity calculation) is
greater than “
RISE
” degrees F per second, the control will stay
in the Capacity Clamp mode.
If control is in the Limiting mode and then
S.G.LS
falls below
SW.L.T
, and LAT is not rising quickly, the control will run the
capacity calculation routine immediately and allow a full stage
to come back on if desired this first time through upon recovery.
This will effectively override the “max capacity stage” clamp.
In addition to the above checks, it is also possible at low cfm for
the supply-air temperature to rise and fall radically between ca-
pacity calculations, thereby impacting the limit switch tempera-
ture. In the case where supply-air temperature (LAT) rises above
the control point (
HT.C.P
) + the cutoff point (
LAT.L
) the control
will run the capacity calculation routine immediately and drop a
stage of heat. Thereafter, every time the capacity calculation rou-
tine runs, provided the control is still in the LAT cutoff mode
condition, a stage will drop each time through. Falling back be-
low the cutoff point will turn off the LAT cutoff mode.
CONTROL BOARD INFORMATION
Integrated Gas Control (IGC)
One IGC is provided with each bank of gas heat exchangers.
One is used on low heat size 030-050 units. Two are used on
high heat size 030-050 units and low heat 055-100 units. Three
are used on high heat 055-100 units. The IGC controls the di-
rect spark ignition system and monitors the rollout switch, lim-
it switches, and induced-draft motor Hall Effect switch. For
units equipped with modulating gas heat, the IGC in the modu-
lating gas section uses a pressure switch in place of the Hall Ef-
fect sensor. The IGC is equipped with a LED (light-emitting
diode) for diagnostics. See Table 57.
Table 57 — IGC LED Indicators
NOTES:
1. There is a 3-second pause between error code displays.
2. If more than one error code exists, all applicable error codes will be
displayed in numerical sequence.
3. Error codes on the IGC will be lost if power to the unit is interrupted.
Integrated Gas Control Board Logic
This board provides control for the ignition system for the gas
heat sections.
When a call for gas heat is initiated, power is sent to W on the
IGC boards. For standard 2-stage heat, all boards are wired in
parallel. For staged gas heat, each board is controlled separate-
ly. When energized, an LED on the IGC board will be turned
on. See Table 57 for LED explanations.
STAGE
RELAY OUTPUT
CAPACITY
%
Heat 1
Heat 2
Heat 3
Heat 4
Heat 5
Heat 6
MBB-RLY8
TR1-CR
SCB-RLY1
SCB-RLY2
SCB-RLY3
SCB-RLY4
IGC2
MGV2
IGC1
MGV1
IGC3
MGV3
MIN
MAX
0
OFF
OFF
OFF
OFF
OFF
OFF
0
0
1
ON
OFF/ON*
OFF
OFF
OFF
OFF
9
33
2
ON
OFF/ON*
ON
OFF
OFF
OFF
34
58
3
ON
OFF/ON*
ON
ON
OFF
OFF
43
67
4
ON
OFF/ON*
ON
OFF
ON
OFF
59
83
5
ON
OFF/ON*
ON
ON
ON
OFF
68
92
6
ON
OFF/ON*
ON
ON
ON
ON
76
100
NUMBER
OF
STAGES
HT.ST
CONFIG
UNIT
SIZE
50P
HEAT
SIZE
VOLTAGE
1
6
030-070
Low, Medium
208/230
6
030-070
All
380,460,575
2
7
030-050
High
208/230
8
055-070
High
208/230
STAGE
RELAY OUTPUT
CAPACITY (%)
Heat1
Heat2
Min.
Max.
0
OFF
OFF
0
0
1
ON
ON
0
100
STAGE
RELAY OUTPUT
CAPACITY (%)
Heat1
Heat2
Min.
Max.
0
OFF
OFF
0
0
1
ON
OFF
0
67
2
ON
ON
0
100
STAGE
RELAY OUTPUT
CAPACITY (%)
Heat1
Heat2
Min.
Max.
0
OFF
OFF
0
0
1
ON
OFF
0
50
2
ON
ON
50
100
ERROR CODE
LED INDICATION
Normal Operation
On
Hardware Failure
Off
Fan On/Off Delay Modified
1 Flash
Limit Switch Fault
2 Flashes
Fame Sense Fault
3 Flashes
Five Consecutive Limit Switch Faults
4 Flashes
Ignition Lockout Fault
5 Flashes
Ignition Switch Fault
6 Flashes
Rollout Switch Fault
7 Flashes
Internal Control Fault
8 Flashes
Software Lockout
9 Flashes
Summary of Contents for Weathermaster 48P2030-100
Page 130: ...130 Fig 19 Typical Power Schematic Sizes 040 075 Shown ...
Page 131: ...131 Fig 20 Main Base Board Input Output Connections ...
Page 132: ...132 Fig 21 RXB EXB CEM SCB Input Output Connections ...
Page 133: ...133 Fig 22 Typical Gas Heat Unit Control Wiring 48P030 100 Units Shown ...
Page 134: ...134 Fig 23 Typical Electric Heat Wiring 50P030 100 Units Shown ...
Page 135: ...135 Fig 24 Typical Power Wiring 115 V ...
Page 136: ...136 Fig 25 Typical Gas Heat Section Size 030 050 Units Shown ...
Page 138: ...138 Fig 27 Component Arrangement Size 030 035 Units ...
Page 139: ...139 Fig 28 Component Arrangement Size 040 075 Units ...
Page 140: ...140 Fig 29 Component Arrangement Size 090 100 Units ...
