(Figure 33 and 34) illustrate two examples of tying in to
existing duct work. Directing air in the right direction will
reduce reverse flow when the existing furnace blower is off.
Some reverse flow will not cause any problems.
CAUTION: Tie-ins into existing duct work must be
down stream from the existing furnace.
NOTE: When the central heating blower is in operation, it
removes air from the room containing the fireplace. If this
room can be closed off from the rest of the house (e.g. with
a door), a grille with at least a 100 square inch open area
must be installed to allow the air to return to the fireplace.
Otherwise periodic smoking from the fireplace will result.
9. Wire the blower to a 115 volt, 15 amp breaker through
the terminal block provided. The variable speed switch pro-
vided should be installed in a convenient location near the
fireplace so the blower can be shut off during refuelling.
The blower transformer relay should be placed in an
accessible location near the blower. It should be mounted
in a 4x4 electrician’s box. You have two options of how you
can connect the central heat blower to the blower control
assembly. Follow the wiring diagram on (Figure 42).
a) If you would like the blower to turn on when the thermo-
stat calls for heat, first locate the thermostat in the princi-
pal room heated by the duct system (this is the most pop-
ular use of the central heat blower). Do not install it in the
room where the fireplace is installed. We recommend an
electrician wire the following. There are yellow, black and
red wires coming out of the relay as shown in the wiring
diagram. Connect the wire from #4 of the terminal block to
the yellow relay wire and the black transformer wire with a
wire marrette. Connect the black relay wire to the variable
speed switch and leave the red wire unconnected with a
wire marrette attached for protection. Connect the neutral
(the white wire) to the wire from #6 terminal (see Figure
32).
b) If the fireplace is in a small room and/or you would like
the central heat blower to remove air from this room when
it becomes too hot, locate the thermostat in the room with
the fireplace (this is a less common use of the central heat
blower). We recommend an electrician wire the following.
There are yellow black and red wires coming out of the
relay as shown in the wiring diagram. Connect the wire
from #4 of the terminal block to the yellow relay wire and
the black transformer wire with a wire marrette. Connect
the red relay wire to the variable speed switch and leave
Page 23
DELTA
black
white
ground (bare)
speed
control
thermo-
stat
BLACK
for
heating ther-
mostat.
RED
for cool-
ing thermo-
stat.
to thermostat
to terminal
NBV
blower con-
trol detail
blower
blower con-
trol
terminal
terminal detail
Figure 32: Wiring for the central heat system
110 V
Colours are represented as fol-
lows (unless otherwise noted)
to speed
control
to blower
