Specifications magic-pak: hw/hwc, Refer to figure 2-3 – Armstrong World Industries HWC PREMIER 183 User Manual
Page 28
SPECIFICATIONS
Magic-Pak: HW/HWC
2-18
SRM-HW/HWC 2/99
Detailed Sequence - HWC122, 182, 242, 302
(w/Fenwal Triton 2461D DSI Ignition Control)
Refer to Figure 2-3
POWER
Line Voltage
When the service disconnect switch is closed, power is
sent to the unit (unit in standby, no signal from the
thermostat
). Power (208 - 230 volts A/C) is supplied
to both black wires located in the junction block on top
of the unit.
Line voltage will be present at the following locations:
First black wire
1.
L-1
on the
ignition control
2.
L-1
on the
contactor
3.
L-1
on the
blower control board
4.
Terminal on the
transformer
marked
208V
or
240V
(whichever is being used)
Second black wire
1.
Supplies power to the
induced draft blower
2.
L-2
on the
contactor
3.
Common terminal on the
transformer
4.
T-2
on the
contactor
5.
Red wire on the
R
terminal of the
compressor
6.
Red wire to the common terminals on the
capaci-
tors
Low Voltage (24 VAC)
With the unit at rest (no call from the
thermostat
), 24
volts A/C will be found at these points:
1.
Red wire exiting the top of the unit
2.
Terminal marked
24 VAC
on the
ignition control
3.
Terminal
R
on the
blower control board
CALL FOR HEAT
Line Voltage
The
thermostat
closes the circuit between
R
and
W
.
The following is the sequence of operation for the line
voltage side of the unit:
1.
Terminal
TH
(24-volt) energizes on the
ignition
control
, causing the relay in the
ignition control
to close. This sends line voltage to the terminal
marked
IND
, causing the
induced draft blower
to
start.
2.
When
W
energizes, a 24-volt signal is also sent to
the
W
terminal on the
blower control board
. The
24-volt signal to the
blower control board
starts
the timer on the board. After 60 seconds, the heat
speed relay on the
blower control board
closes.
This sends line voltage from the terminal marked
HEAT
to the
circulating air blower
, starting the
blower. The
induced draft blower
and the
circu-
lating air blower
continue to operate until the heat
call is satisfied, interrupting the circuit between
R
and
W
. The
W
terminal de-energizes, causing the
blower relay to open approximately 90 seconds
later. This interrupts the line voltage to the
circulat-
ing air blower
and the blower shuts down.
Low Voltage
1.
A call for heat closes the circuit in the
thermostat
between
R
and
W
, sending a 24-volt signal to the
white wire on the unit.
2.
The white wire goes to the
C
terminal on the
limit
switch
,
ignition control
terminal
TH
and terminal
W
on the
blower control board
.
3.
When
W
energizes, the timer starts a countdown to
blower “on”. The blower starts in approximately 60
seconds.
4.
The 24-volt signal sent to terminal
TH
closes the
relay in the
ignition control
. This starts the
induced draft blower
by energizing terminal
IND
on the
ignition control
.
5.
As the
induced draft blower
comes up to speed
and creates enough negative pressure, the
pres-
sure switch
closes. The 24-volt signal from the
pressure switch
energizes terminal
P.SW
, causing
the
ignition control
to start a trial for ignition
(sparking).
6.
As the trial for ignition starts, the
V1
terminal on the
ignition control
energizes. At the same time, a 24-
volt signal is sent to the
gas valve
, opening the
valve. The unit continues to operate as long as
W
is
energized.
7.
When the call for heat is satisfied, the circuit be-
tween
R
and
W
is interrupted.
8.
With
W
de-energized, the
gas valve
closes immedi-
ately and the
induced draft blower
shuts down
several seconds later.
9.
The
blower control board
starts a countdown to
blower “off”. Approximately 90 seconds later, the
blower shuts down.