Sterling TUBULAR GAS FIRED DIRECT SPARK PROPELLER UNIT HEATERS GG-30 - Manual (Page 10)

10
HAZARDOUS VOLTAGE!
DISCONNECT ALL ELECTRIC
POWER INCLUDING REMOTE
DISCONNECTS BEFORE
SERVICING. Failure to
disconnect power before
servicing can cause severe
personal injury or death.
Standard units are shipped for use on 115 volt, 60 hertz,
single phase electric power. The motor name-plate and
electrical rating of the transformer should be checked
before energizing the unit heater electrical system. All
external wiring must conform to the latest edition of
ANSI/NFPA No. 70, National Electrical Code, and
applicable local codes; in Canada, to the Canadian
Electrical Code, Part 1, CSA Standard C22.1.
Do not use any tools (i.e. screwdriver,
pliers, etc.) across terminals to check for power. Use
a voltmeter.
It is recommended that the electrical power supply to
each unit heater be provided by a separate, fused, and
permanently live electrical circuit. A disconnect switch of
suitable electrical rating should be located as close to
the gas valve and controls as possible. Each unit heater
must be electrically grounded in accordance with the
latest edition of the National Electrical Code, ANSI/NFPA
No. 70, or CSA Standard C22.1. Refer to Figures 7, 8,
9, 10A, 10B, 10C, 11A, 11B and 11C.
ELECTRICAL CONNECTIONS
THERMOSTAT WIRING AND LOCATION:
NOTICE: The thermostat must be mounted on a
vertical, vibration-free surface, free from air currents,
and in accordance with the furnished instructions.
Mount the thermostat approximately 5 feet (1.5m) above
the floor, in an area where it will be exposed to a free
circulation of average temperature air. Always refer to
the thermostat instructions, as well as our unit wiring
diagram, and wire accordingly. Avoid mounting the
thermostat in the following locations:
1. Cold Areas- Outside walls or areas where drafts may
affect the operation of the control.
2. Hot Areas- Areas where the sun's rays, radiation,
or warm air currents may affect the operation of the
control.
3. Dead Areas- Areas where the air cannot circulate
freely, such as behind doors or in corners.
THERMOSTAT HEAT ANTICIPATOR ADJUSTMENTS:
The initial heat anticipator setpoint should equal the
thermostat's current amperage draw when the unit is
firing. This setpoint should be measured for the best
results. Use the recommended ranges for a guide. If
further information is needed, consult your thermostat
manufacturer's instructions.
Recommended heat anticipator setting .35 Amps
NOTICE: The start-up fan delay should not exceed
30 seconds from a cold start.
IMPORTANT: For all wiring connections, refer to the
wiring diagram shipped with your unit (either affi xed
to the side jacket or enclosed in the installation
instructions envelope). Should any original wire
supplied with the heater have to be replaced, it
must be replaced with wiring material having a
temperature rating of at least 105° C.
Figure 9 - T834H or T834N
Thermostat Wiring
Figure 7 - Low-voltage Thermostat Wiring
Single Stage
R G W1 W2
W R
G
D6922C
Figure 8 - Low Voltage Thermostat Wiring
Two Stage