Reznor UDBS Unit Installation Manual - Manual (Page 20)

Form I-UDB, P/N 202658 R14, Page 20
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, with CSA Standard C22.1. In addition, the installer should be aware of any
local ordinances or gas company requirements that might apply.
7.0 Electrical
Supply and
Wiring
6.0 Mechanical
(cont’d)
6.4 Blowers, Belts,
and Drives
(cont’d)
6.4.3 Blower and Belt Guards
Guard options are designed to provide complete protection from the rotating drive and
blower. Guards ordered as Option AZ6 or AZ7 are factory installed. Guards ordered as
Option CD10 or CD12 are shipped separately for field installation. The blower guard
only (Options AZ7 and CD12) is for Sizes 30-125 which have a direct drive motor. Both
guards are used on Sizes 150-400 which have a belt drive. The belt guard includes
a ground wire and screw. When the belt guard is field installed, be sure to attach the
ground wire and insert the screw into one of the holes in the blower housing.
Blower Guard
in Options
AZ6, AZ7,
CD10, and
CD12
Belt Guard in
Option AZ6 and CD10
FIGURE 14 - Optional
Belt and Blower Guards
are either factory or
field installed
(3) #10
Sheetmetal
Screws
(with the
transformer)
500V
A
Transformer Transformer
Bracket
(factory
installed)
Side of
Heater
Opposite
the Control
Compartment
FIGURE 15 - Sizes 150-
400 with 460 or 575
supply voltage require
installation of a 500VA
Stepdown Transformer
Instructions for Installing the 500 VA Transformer
supplied with Size 150-400 units ordered for 460V or
575V supply (Components listed in Paragraph 3.2)
1. The transformer is shipped in its own carton. Remove the
transformer and the screws.
2. On the side of the heater opposite the access door, locate
the factory-installed bracket. Position the transformer on the
bracket and use the screws to attach the transformer.
3. Refer to the wiring diagram on the heater and the
connection information on the transformer. The transformer
has dual primary and secondary voltages, so be careful to
make the connections correctly.
Route the supply wiring in conduit from the transformer to
the entrance at the rear of the heater. Conduit retainers may
be attached to the edges of the heater cabinet or blower
back.
CAUTION: If any of the original wire as supplied with the appliance must be replaced,
it must be replaced with wiring material having a temperature rating of at least 105°C,
except for limit control, flame rollout, and sensor lead wires which must be 150°C.
See Hazard Levels, page 2.
7.2 Supply Wiring Check the rating plate on the heater for the supply voltage and current requirements.
A dedicated line voltage supply with disconnect switch should be run directly from the
main electrical panel to the heater. All external wiring must be within approved conduit
and have a minimum temperature rise rating of 60°C . Conduit must be run so as not to
interfere with the heater access panel.
If an optional stepdown transformer, Option CG2 or CG4, was ordered, follow the
instructions shipped with the option package for attaching the transformer to the heater.
For wiring connections, refer to the transformer and the wiring diagram on the heater.
If the unit is a Size 150-400 with a 460 or 575 supply voltage, a stepdown transformer
is shipped separately and must be field installed on the unit. See the shipped-separate
list of parts in Paragraph 3.2 and follow the instructions in FIGURE 15.