6
Figure 8: 2-stage heating & 1-stage air conditioning & heat
pump thermostat
Figure 9: 2-stage heating & 2-stage air conditioning & heat
pump ther dehumidification mode
2.5.1- Anticipator adjustment (if required) on thermostat
equipped with heat anticipator adjustment
Some thermostats are equipped with a heat anticipator that must
be adjusted according to the instructions supplied. This is to
ensure that the heating mode is comfortable and economical.
Generally speaking, on a single stage thermostat, a reading of
the current must be taken with an ammeter as follows:
1. Move the anticipator to its highest setting, rendering it
ineffective.
2. Remove the wire from the W1 terminal and connect an
ammeter between the terminal and the wire.
3. Call for heat by raising the set point on the thermostat and
allow the furnace to run for 3 to 4 minutes to reach its peak
output.
4. Once the current has stabilized, a reading should be taken
and the anticipator adjusted to that value. If longer heating
cycles are desired, the anticipator can be set to a higher
value
2.5.2- Air ducts
The ducts must be sized such a way as to accommodate the
specified airflow and the available static pressure. Refer to the
applicable local and/or national installation codes.
Insulate the ducts that lead through non-heated areas. Use
flexible supply and return air connectors to avoid the
transmission of vibration. To make the unit run even quieter, the
installer should:
a. Use two elbows between each outlet and the supply and
return air plenum;
b. Cover the vertical sections of the supply and return air duct
with soundproofing material;
c.
Use baffles in short radius elbows;
d. Use flexible hangers to suspend the ducts.
A heat pump or an air conditioner can be added to this furnace,
in either the supply or return air duct. Carefully follow the
instructions provided with these appliances to ensure proper
installation and hook-up to the electric furnace. Refrigerant and
drainage pipes must in no way hinder access to the furnace
panels.
2.6- SUPPLY AIR ADJUSTMENTS
Fan Control Board taps are used by the installer to configure a
system. The ECM motor uses the selected taps to modify its
operation to a pre-programmed table of airflows (Refer to Table
3 and Table 4). Airflows are based on system size or mode of
operation and those airflows are modified in response to
thermostat inputs such as dehumidification request.
The U
NIQUE
furnace must be configured to operate properly with
system components with which it is installed. To successfully
configure a system (see information printed on circuit board
label located next to select pins), move the 6 select wires to the
pins which match the components used. (Refer to Figure 10
below)
Figure 10 : Fan Control Board
2.6.1- HEAT KW/CFM adjustment
Installer must verify (factory set) the electric heat airflow
adjustment required for kW size heater installed.
The select pins are marked 25, 23/20, 18/15, 10 (for ½ HP ECM
motor unit) and 30/27, 25, 23, 20, (for 1.0 HP ECM motor unit).
Refer to the unit wiring diagram and select the pin for the kW
size heater being used (Refer to Figure 10 and Figure 16).
The airflow must be large enough for safe and continuous
operation. (Refer to Table 3 and 4 for airflow delivery CFM).
