Watlow FIREBAR Circulation Heater - Manual (Page 4)

WATLOW IND.
FIREBAR® Circulation Heater Installation & Maintenance Manual
I&M Number: 316-42-1-1 Page: 4
Date: 06-11-08 Rev: 2.00
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WATLOW IND.n # 6 INDUSTRIAL LOOP RD. n HANNIBAL MO, 63401n PHONE 573-221-2816 n FAX 573-221-3723
When installing piping connections, care should be taken to avoid supporting the tank by the nozzles.
Mounting blocks are provided to help prevent this. Provisions for thermal expansion and contraction
should be considered, slotted bolt holes in one of the mating mounting pads would do adequately.
Installation of an isolation valve and pressure relief valve is recommended but not provided. Rating of
valves should not exceed the ANSI class 150 flange rating. Two 1/2" FNPT couplings are provided for
drainage and installation of valves.
DANGER: HAZARD OF FIRE. Electric heaters are capable of developing high temperatures so extreme
care should be taken to locate heaters in safe environments. Mounting heaters in atmospheres
containing combustible gases and vapors should be avoided. According to article 501 of the NEC, the
maximum surface temperature of the heater shall not exceed 80 % of the auto-ignition of the surrounding
atmosphere when the heater is continuously energized. Care should also be taken to keep combustible
materials far enough away to be free of the effects of high temperatures.
5. Wiring
WARNING; HAZARD OF ELECTRIC SHOCK. Any installation involving electric heaters must be
grounded to earth to eliminate shock hazard.
Electrical wiring to the heaters must be installed in accordance with the National Electric Code and any
state and local electrical code by qualified personnel.
Consult wiring diagram supplied with the unit for correct feeder or leadwire connections. If wiring
diagram is not supplied, the factory should be consulted for the appropriate wiring diagram. Feeder wire
should be properly selected based on amperage, electrical power rating, ambient temperature, and type
of environment. Feeder wire should also be housed in either rigid or flexible conduit which carries the
same classification as the heater enclosure. It is the users responsibility to properly size and install
feeder wire.
Feeder wire line connections may be made directly to stud terminals or box type compression fittings.
Box type compression fittings will accept a #4 AWG maximum wire while stud terminals will accept a
#10 ring connector(T&B, Amp, etc.). It is essential that these connections be tight. Stud terminals should
be tightened to a maximum torque of 20 in-lbs while the bottom nut is supported. Ground connection
(color coded "green") is supplied inside the housing for ground wire.
Line voltage must be equal to or less than rating stamped on the heater assembly. Some units are
supplied as dual voltage . Example: 240V / 480V, check wiring diagram supplied with the unit to make
sure which scheme was used. In most cases (unless specified by customer) units are wired for the
higher voltage.
Thermostats can be supplied with flange heaters. Consult the wiring diagram supplied with the heater
for the suggested wiring of thermostats. For safe operation of thermostats, consult Installation and
Maintenance manual for thermostats that is attached.
Thermostats should not be used as an "OFF" device; the use of a disconnect switch or circuit breaker is
recommended. The disconnect switch will allow isolation of the heater when maintenance of the heater
is required.
Start Up
Before energizing the heater the following items should have been checked with the heater power
disconnected:
1. Electrical termination is tight and wiring is per wiring diagram supplied with heater
2. Proper disconnecting means and fusing have been installed
3. The voltage rating of the heater is the same as that being applied