Mestek IIEB-11, Installation & Parts Manual

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* Ther mostat wires tagged “W” and “G” must be
connected together except when using a general purpose
"SPDT" 24VAC relay and a standard thermostat with
subbase, or when using Honeywell T834H-1009 or
T834H-1017 thermostats. Also refer to Figure 8 for other
wiring connections.
Figure 8 - C1267G
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 as a guide. If
further information is needed, consult your thermostat
manufacturer's instructions.
Recommended Heat Anticipator Setting Ranges:
25 ft. (7.6m) 50 ft. (15.2m)
Gas Ignition Type T'stat Wiring T'stat Wiring
For Power Vented Units: 0.85 to 0.90 A 0.90 to 1.1 A
Intermittent (Spark) Max. Setting
on T'stat
FAN TIME DELAY CONTROL
Leads from time delay controls are factory wired to
the junction box. The fan control is a time delay relay
(approximately 45 seconds ON, 65 seconds OFF). The
fan control is rated at 17 amps.
NOTICE: The start-up fan delay must not exceed 90
seconds from a cold start.
IMPORTANT: For all wiring connections, refer to the
wiring diagram that your unit is equipped with (either
affi xed to the side jacket or enclosed in your unit's
installation instruction 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.
Should any high limit switch wires have to be
replaced, they must be replaced with wiring material
having a temperature rating of 200°C minimum.
11
ELECTRICAL CONNECTIONS
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 on the transformer should be checked
before energizing the unit heater electrical system. All
external wiring must conform to the latest edition of
the 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 the terminals to check for power.
Use a voltmeter.
The transfor mer supplied with this unit heater is
internally fused. Any overload or short circuit will ruin
the transformer.
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 for each unit heater 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
Electric Code, ANSI/NFPA No. 70 or CSA Standard
C22.1.
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 (1.5 m) 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 control operation.
3. Dead areas - Areas where air cannot circulate freely,
such as behind doors or in corners.