0 electrical supply and wiring, 1 general, 2 supply voltage and wiring – Reznor X Unit Installation Manual User Manual
Page 16: 3 thermostat and control wiring

Form I-X, P/N 150491 R10, Page 16
60°C. Be sure conduit from the disconnect switch will not 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 of currently manufactured heaters are on
pages 17-18.
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, energy
cutoff, and sensor
lead wires which
must be 150°C.
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 according to
1.25 times the maximum total input amps.
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 disconnect switch and removable panels.
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 (1.5M) 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
the instructions with the thermostat.
If more than one unit is cycled from one thermostat, separately activated relays must
be substituted at unit thermostat connections.
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.
If the low voltage (24 volt) thermostat is equipped with a heat anticipator to level out
unit cycling for optimum temperature control, set the anticipator at full load control
AMPS.
24 Volt Controls - Maximum Amps
(24 volt Transformer has 20 VA capacity)
Single-Stage Valve .7A
Fan Control Heater .12A
Two-Stage Valve
.33A Time Delay Relay
Heater
.1A
Maxitrol System
.5A
Spark Ignition
.1A
Relay Coil
.12A
7.0 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.
Run a separate line voltage supply with fused disconnect switch directly from the main
electrical panel to the furnace, making connection to leads in the junction box. All exter-
nal wiring must be within approved conduit and have a minimum temperature rise of