Dettson Lowboy 154 Series, Installation Instructions And Homeowner'S Manual

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2.11 SUPPLY AIR ADJUSTMENTS
(ECM VARIABLE SPEED
MOTORS)
On units equipped with ECM variable speed blower mo-
tors, 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, airflow tables and the wiring
diagram in this manual for the proper settings.
Table 3 – Airflow adjustments - Heating mode
SW1-HEAT
INPUT
DIP Switch Positions
USGPH
1 2 POSITION
OFF OFF A
0.90
ON OFF B
1.10
OFF ON C*
N/A
ON ON D*
N/A
*Alternate adjustments for a higher air temperature rise
Table 4 – Airflow adjustments - Air conditioning
mode
SW2-COOL
INPUT
DIP Switch Positions
USGPH
1 2 POSITION
OFF OFF A
5.0
ON OFF B
4.0
OFF ON C
3.5
ON ON D
3.0
Table 5 – Airflow adjustments - All modes
SW3-ADJ (Adjustment)
CFM HT G. CFM A/G.
DIP Switch Positions
% Increase % Increase
1 2
POSITION
or decrease or decrease
OFF OFF A
0% 0%
ON OFF B
10% 10%
OFF ON C -10% -10%
ON ON D
N/A 0%
Table 6 – Delay adjustments - Heating mode
SW4-Delay
INPUT
DIP Switch Positions
USGPH
1 2 POSITION
OFF OFF A
0.90
ON OFF B
1.10
OFF ON C
1.10
ON ON D*
N/A
*Alternate adjustments for both input rate (refer to air-
flow table)
2.12 INSTALLATION OF
ACCESSORIES
WARNING
E
LECTRICAL SHOCK HAZARD
.
Turn OFF electrical power at the fuse box or ser-
vice panel before making any electrical connec-
tions and ensure a proper ground connection is
made before connecting line voltage.
Failure to do so can result in death or bodily injury.
2.12.1 Humidifier (HUM)
The electronic board supplies 120 VAC for a humidifier
on the HUM terminal. 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.
2.12.2 Electronic Air Cleaner (EAC)
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,
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