Reznor B Unit Installation Manual - Manual (Page 23)

Form I-F/B, P/N 98126 R21, Page 23
4. Cut the crimped cap from the end of the wire that you intend to use and strip the
insulation.
5. Disconnect the factory-wired connection and re-wire, using the newly stripped
wire.
6. Put a wire nut on the end of the blower motor wire that was disconnected.
7. Replace the heater side panel and turn on the gas and the electric.
Blower Model Sizes 50-400 with Belt Drive
The belt drive on these units is equipped with an adjustable pulley which permits
adjustment of the blower speed. Follow these instructions to adjust the blower speed.
1. Turn off the gas and the electric power.
2. Loosen belt tension and remove the belt.
3. Loosen the set screw on the side of the pulley away from the motor.
4. To increase the blower speed, decreasing outlet temperature, turn the
adjustable half of the pulley inward. To decrease the blower speed, increasing
the outlet temperature, turn the adjustable half of the pulley outward. One turn of
the pulley will change the speed 8-10%.
5. Tighten the set screw on the flat portion of the pulley shaft.
6. Replace the belt and adjust the belt tension. Adjust tension by turning the adjusting
screw on the motor base until the belt can be depressed 1/2-3/4" (13-19mm). (See
FIGURE 23.) Re-tighten the lock nut on the adjusting screw.
7. Turn on the gas and electric. Light the heater following the instructions on the
lighting instruction plate.
8. Check the motor amps with an amp meter. The maximum motor amp rating on the
motor nameplate must not be exceeded.
CAUTION: An external duct system static pressure not within the
limits shown on the rating plate or improper adjustment of the
motor pulley or belt may overload the motor and/or damage the
heat exchanger.
Blower Rotation
Each blower housing is marked for proper rotation. Rotation may be changed on sin-
gle-phase motors by re-wiring in the motor terminal box. Three-phase motors may be
reversed by interchanging two wires on the 3-phase supply connections.
7. Electrical
Supply and
Wiring
7.1 General
All electrical wiring and connections, including electrical grounding MUST be made in
accordance with the National Electric Code ANSI/NFPA No. 70 (latest edition) or, in
Canada, the Canadian Electrical Code, Part I-C.S.A. Standard C22.1. In addition, the
installer should be aware of any local ordinances or gas company requirements that
might apply.
7.2 Supply Voltage
and Wiring
Check the rating plate on the heater for the supply voltage and current requirements.
A separate line voltage supply with fused disconnect switch should be run directly from
the main electrical panel to the heater. All external wiring must be within approved con-
duit and have a minimum temperature rise of 60°C. Conduit from the disconnect switch
must be run so as not to interfere with the service panels of the heater.
The electrical supply connects at the top back of the heater in the left corner (left when
facing the back of the heater). A threaded hole is provided for a standard 1/2" electrical
fitting. See FIGURE 24. The wiring access panel is easily removed for field connec-
tions. Consult the wiring diagram supplied with your heater. Replace the panel after the
wiring connections are made.
If the heater has field-installed options that require electrical connections, consult the
instruction sheet and wiring diagram supplied in the option package.
A fan-type heater may be equipped with a built-in fused disconnect switch (Option
AI-1). If the heater is equipped with a built-in disconnect switch, a two-position toggle
(on/off) switch is located near the electrical supply access panel (See FIGURES 24