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9
Figure 8: Blower start/stop delays, board #1158
2.12 SUPPLY
AIR
ADJUSTMENTS
(ECM
VARIABLE
SPEED
MOTORS)
On units equipped with ECM variable speed blower motors,
the air supply must be adjusted based on heating/air
conditioning output. The start/stop delays of the blower must
also be adjusted by positioning the DIP switches on the
electronic board. Refer to the following tables, air flow Table 8
and the wiring diagram in this manual for the proper settings:
Table 2: Air adjustments, heating mode
SW1 – HEAT
DIP Switch Positions
1 2
POSITION
Input
USGPH
OFF OFF
A
0.68
ON OFF
B
0.80
OFF ON
C
*
0.68
ON ON D
*
0.80
*
Alternate adjustment with higher temperature rise
Table 3: Airflow adjustments, air conditioning mode
SW2 – COOL
DIP Switch Positions
1 2
POSITION
Output
Tons
OFF OFF
A
3.5
ON OFF
B
3.0
OFF ON
C
2.5
ON ON
D
2.0
Table 4: Airflow adjustments, all modes
SW3 – ADJ (Adjustment)
DIP Switch Positions
1 2
POSITION
CFM HTG.
% increase
or decrease
CFM A/C
% increase
or decrease
OFF OFF
A
0%
0%
ON OFF
B
+10%
+10%
OFF ON
C
-10%
-10%
ON ON
D
N/A
0%
Table 5: Delay adjustments, heating mode
SW4 – Delay
DIP Switch Positions
1 2
POSITION
Input
USGPH
OFF OFF A
0.68
ON OFF B 0.80
OFF ON C ALL
ON ON D ALL
2.13 INSTALLATION
OF
ACCESSORIES
WARNING
Electrical shock hazard.
Turn OFF electrical power at the fuse box or service
panel before making any electrical connections and
ensure a proper ground connection is made before
connecting line voltage.
Failure to do so can result in death or bodily injury.
2.13.1 Humidifier
(HUM)
The 120 VAC HUM terminal on the electronic board of the
blower is tied directly to terminal 8 of the 9-terminal
connector of the electronic board. It supplies 120 VAC
electric power when the burner is in operation.
A 24 VAC signal can also be supplied from the W and C
terminals on the blower electronic board to activate a
switching relay.
Also refer to the instructions supplied with the accessory.
2.13.2 Electronic Air Cleaner (EAC) (PSC
Model)
The EAC terminal on the electronic board supplies 120
VAC when the blower is operating in the heating or air
conditioning mode. This signal can be used to activate an
electronic air cleaner that is not equipped with an air flow
switch. If the cleaner is equipped with an air flow switch,
the S terminal on the electronic board can be used to
provide a constant supply of 120 VAC.
Also refer to the instructions supplied with the accessory.
2.13.3 Air Conditioner (or Heat Pump)
An air conditioning coil may be installed on the supply air
side ONLY.
WARNING
Poisonous carbon monoxide gas hazard.
Install the evaporator coil on the supply side of the
furnace ducting ONLY.
An evaporator coil installed on the return air side of
the ducting can cause condensation to form inside
the heat exchanger, resulting in heat exchanger
failure. This in turn, can result in death, bodily injury
and/or property damage.
A clearance of 15 cm (6") is required between the bottom
of the coil drain pan and the top of the heat exchanger. If
a heat pump is installed, a “dual-energy” thermostat, or
Summary of Contents for OBM112 Series
Page 17: ...17 Figure 9 Furnace Dimensions ...
Page 18: ...18 Figure 10 Wiring Diagram 4 Speed Motor PSC ...
Page 19: ...19 Figure 11 Wiring Diagram Variable Speed Motor ECM ...
Page 20: ...Figure 12 Parts list with 4 speed motor PSC 20 B50091C ...
Page 22: ...22 Figure 13 Parts list with variable speed motor ECM B50092C ...
Page 24: ......
Page 42: ...Figure 9 Dimensions de la fournaise 18 ...
Page 43: ...19 Figure 10 Diagramme électrique avec moteur 4 vitesses PSC ...
Page 44: ...20 Figure 11 Diagramme électrique avec moteur vitesse variable ECM ...
Page 45: ...Figure 12 Liste de pièces avec moteur 4 vitesses PSC 21 B50091C 21 B50091C ...
Page 47: ...23 B50092C 23 B50092C Figure 13 Liste de pièces avec moteur vitesse variable ECM B50092C ...