L.B. White HW 120 Therma Grow - Manual (Page 12)

Follow steps 1 - 6 on initial start-up after heater installation
by a qualified gas heater service person. For normal start-
up, simply turn thermostat above room temperature. The
heater will start.
1. Open all manual fuel supply valves and check for gas
leaks using approved leak detectors. The gas control
valve on the heater has a manual shut-off feature
incorporated into the valve assembly. Make sure the
indicator on the valve is turned to the “on” position.
See Fig. 9.
FIG. 9
2. Connect the electrical cord to an approved electrical
outlet.
3. Set the thermostat (if supplied) to desired room
temperature.
4. This heater includes a hot surface ignition (HSI)
control module for purposes of controlling the timing
of the ignition process of the heater as well as
monitoring of the safety functions. The HSI module is
contained within the control enclosure.
When the selector switch is positioned to heat, the red
light emitting diode (LED) on the ignition control will
be on. This LED indicates the status of the heater.
The LED is visible through the plastic window of the
control box. A constant light from the LED is an
indicator that the heater is functioning correctly.
Any flash pattern by the LED indicates there is a
problem in the operation of the heater. Refer to the
troubleshooting decal adjacent to the control box for
assistance in troubleshooting. Only qualified and
properly trained personnel shall service or repair the
heater.
On a call for heat, the motor will start and run for five
(5) seconds and then stop. This pre-purge is a safety
feature and a normal operational characteristic prior
to ignition taking place. After the motor has stopped,
the igniter will heat up (approximately 17 seconds).
After igniter warm up time has been achieved, the
motor will start again and shortly thereafter ignition
will occur.
NOTE: It is normal for air to be trapped in the gas
hose on new installations. The heater may
attempt more than one trial for ignition
before the air is finally purged from the line
and ignition takes place.
4. The HSI control will make up to three trials for ignition.
Each trial for ignition will take approximately 20
seconds. The first two trials for ignition will occur
within 40 seconds if ignition is not achieved. A 15
minute wait period will then begin after the second
trial for ignition has taken place. After the 15 minute
time has passed, the third and final trial for ignition
will take place. If ignition is not achieved at this final
trial, the system will lock out, and a three flash pattern
will be indicated by the LED.
6. Do not exceed input rating stamped on nameplate or
manufacturer’s recommended burner orifice pressure
for size orifice(s) used. Make certain that the primary
air supply to main burner is open and free of dust, dirt
and debris for complete, proper combustion.
If the heater is to be shut down for cleaning, maintenance or
repair, follow steps 1 - 5. Otherwise, simply turn thermostat
to off or no heat for standard shut down.
1. Close all manual fuel supply valves.
2. With the heater lit, allow heater to burn off excess fuel
in gas supply hose.
3. Turn the indicator on the gas control to off.
4. Turn thermostat to off or no heat position.
5. Disconnect the heater from the electrical supply.
12
Start-Up Instructions
Shut-Down Instructions
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