6
ELECTRICAL CONNECTIONS
6.1
120V WIRING
The furnace must have a 120 V power supply properly
connected and grounded.
NOTE:
Proper polarity must be maintained for 120 V wiring. If
polarity is incorrect, the control LED status indicator light will
indicate an error code and the furnace will not operate.
Verify that the voltage, frequency, and phase correspond to the
specifications on the rating plate of the unit. Assert that the
service provided by utility is sufficient to handle load imposed
by this equipment. Refer to Table 23 for equipment electrical
specifications.
Use a separate, fused branch electrical circuit with a properly
sized fuse or circuit breaker for this furnace. See Table 23 for
fuse specifications. A readily accessible means of electrical
disconnect must be located within sight of the furnace.
6.2
24V THERMOSTAT WIRING
Make field 24 V connections at the 24 V terminal strip. Connect
terminal Y/Y2 for proper cooling operation. Use AWG No. 18,
color-coded, copper thermostat wire. For wire lengths over 100
ft., use AWG No 16 wire.
6.3
FUSE
The 24 V circuit contains an automotive type, 3-amp fuse
located on the control (R99G016). Any direct shorts during
installation, service, or maintenance could cause this fuse to
blow. Replace only with a fuse of the same ratings.
6.4
THERMOSTATS
A single-stage or two-stage thermostat may be used with the
furnace.
Consult the thermostat installation instructions for
specific information about configuring the thermostat.
6.4.1
Single-Stage thermostat
Use the DIP switches S7-1 and S7-2 (see table 7) to configure
for a single-stage thermostat . Options include a 10-minute
delay on second stage, 20-minute delay on second stage or
an auto setting allowing the module to calculate the time delay
for second stage based on average demand (between 1 and 12
minutes).
Table 7 – Single stage t-stat with 2 stage ECM furnace
S7-1
S7-2
TIME
OFF
OFF
N/A
ON
OFF
10 MIN
OFF
ON
AUTO
ON
ON
20 MIN
Figure 16
Single Stage t-stat and heat pump
6.4.2
Multi-Stage thermostat
The control is set from the factory to be used with a multi-
stage thermostat. Dettson recommend the 2-stage thermostat
R02P033 which can be wired has shown below.
This
configuration allows 2-Stage A/C, 2-Stage Heat pump as well
as 2-Stage gas heating (when configuring dipswitches S7-1 and
S7-2).
Figure 17
2-Stage t-stat and heat pump
6.5
ELECTRIC DIAGRAM
The wiring diagram is shown on figure 32.
6.6
ALTERNATE POWER SUPPLY
Dettson doesn’t recommend to operate the furnace on a
generator or other alternate power supply. If so it must produce
a smooth sinusoidal waveform for compatibility with the furnace
electronics.
The alternate power supply must generate the
same voltage, phase, and frequency (Hz) as shown on the
furnace rating plate.
Power from an alternate power supply that is non-sinusoidal
may damage the furnace electronics or cause erratic operation.
17
Summary of Contents for C105-2-V
Page 24: ...Figure 29 Direct vent clearance 23 ...
Page 25: ...Figure 30 Other than Direct vent clearance 24 ...
Page 32: ...Figure 31 Dimensions 31 ...
Page 33: ...Figure 32 Two Stage ECM Wiring diagram 32 ...
Page 36: ...Figure 33 Exploded view Cxx 2 V part 1 35 ...
