Reznor HRPD (Outdoor Duct Furnaces) Unit Installation Manual - Manual (Page 14)

Form I-RP/HRPD, P/N 132210 R14, Page 14
7.3 Thermostat and
Control Wiring
A thermostat is not standard equipment but is an installation requirement. Use either
an optional thermostat available with the heater or a field-supplied thermostat. Install
according to the thermostat manufacturer's instructions.
A 24-volt thermostat must be used to actuate low voltage gas controls. If line voltage
from the thermostat to the unit is desired, consult the factory representative.
Wiring between the thermostat and the heater must be suitable for a temperature rise
of 60°C. Labeled thermostat leads are provided in the heater junction box for connec-
tion of thermostat wiring.
Thermostats should be located five feet above the floor on an inside wall, not in the
path of warm or cold air currents and not in corners where air may be pocketed. Do
NOT install a thermostat on cold air walls. For specific connection details, refer to
instructions with the thermostat.
If more than one unit is cycled from one thermostat, separately activated relays must
be substituted at unit thermostat connections.
Low voltage (24 volt) thermostats may be equipped with heat anticipators which level
out unit cycling for optimum temperature control. Set anticipator at full load control
AMPS.
CAUTION: Make sure the thermostat has an adequate VA rating for the
total requirements. Add coil rating of all relays and match thermostat
rating. See Hazard Levels, page 2.
24V Controls - Maximum Amps
(24V Transformer has 20VA capacity)
Single-Stage Valve - .6
Two-Stage Valve - .6
Maxitrol System - .5
Spark Ignition System - .1
Fan Control Coil - .12
Time Delay Relay Heater - .1
Relay Coil - .12
All external wiring must be within approved conduit 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 furnace.
If the heater has field-installed options that require electrical connections, consult the
instruction sheet and wiring diagram supplied in the option package.
Specific wiring diagrams that include standard and factory-installed options are included
with the heater. Typical wiring diagrams are on pages 15 and 16.
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, optional bypass damper
combustion air safety circuit (Option AG39, AG40, AG41, or AG42), and
sensor lead wires which must be 150°C. See Hazard Levels, page 2.
Disconnect Switch
A disconnect switch is a required part of this installation. Switches are available, as
options or parts, or may be purchased locally. When ordered as an optional compo-
nent, the disconnect switch is shipped separately.
The disconnect switch may be fusible or non-fusible. When providing or replacing fuses
in a fusible disconnect switch, use dual element time delay fuses and size to 1.25 times
the maximum total input amps as stated on the unit rating plate. When installing, be
careful that the conduit and switch housing are clear of furnace panels and inspection
plates. Allow at least four feet (1.2M) of service room between the switch and remov-
able panels.
7.0 Electrical
Supply and
Connections
(cont'd)
7.2 Supply Voltage and Wiring (cont'd)