Dettson AMT154SDMA, Installation Instructions And Owner'S Manual

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2.10.1 Supply air adjustment (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 and the wiring
diagram in this manual for the proper settings:
Table 3: Heating Mode
SW1 – HEAT
DIP Switch Positions
1 2 POSITION
Input
USGPH
OFF OFF A 0.90
ON OFF B 1.10
OFF ON C* N / A
ON ON D* N / A
Table 4: Air Conditioning Mode
SW2 – COOL
DIP Switch Positions
1 2 POSITION
Output
Tons
OFF OFF A 5.0
ON OFF B 4.0
OFF ON C 3.5
ON ON D 3.0
Table 5: CFM adjustment - 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 6: Delay adjustments - Heating Mode
SW4 – Delay
DIP Switch Positions
1 2 POSITION
Input
USGPH
OFF OFF A 0.90
ON OFF B 1.10
OFF ON C 1.10
ON ON D
*
N / A
2.11 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.
2.11.1 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.
2.11.2 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,
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.
2.11.3 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
other control is recommended, in order to prevent the
simultaneous operation of the furnace and the heat pump.
It also prevents a direct transition from heating by way of
the heat pump to heating with oil. Refer to the thermostat
instructions or those of another control used for the proper
wiring.
If a coil blower compartment is used, install air tight,
motorized and automatic air dampers. Cold air coming
from the coil and passing across the furnace can cause
condensation and shorten the life of the heat exchanger.
2.11.4 Emergency Heating Mode – Variable
Speed Motor (ECM)
If the ECM blower motor is defect and that no spare are
available right away, you can temporarily replace it with a
conventional fractional PSC blower motor. Connect
neutral wire to neutral terminal on the control panel of the
machine and the hot line to the EAC terminal. This one is
working as long as heating or cooling is requested, and
the blower will work until a new ECM motor is installed.
IMPORTANT
We recommend to use this mode only for a short period
since it affects the efficiency of the unit and the user
comfort.