Roberts Gorden DF, Инструкция по установке, эксплуатации и обслуживанию

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DF-S
ERIES
I
NSTALLATION
, O
PERATION AND
S
ERVICE
M
ANUAL
56
SECTION 11: OPERATION AND MAINTENANCE
This heater is equipped with a direct spark ignition
system.
11.1 Sequence of Operation
The DF-Series heater is a dual firing heating unit that
must be connected to a two-stage thermostat (P/N -
90425412) for correct operation. The ROBERTS
GORDON
®
two-stage thermostat uses an algorithm
that controls whether the heater operates on high or
low fire. The algorithm output will vary based on load
conditions. For example, if the thermostat does not
sense a heat rise during a heat cycle within a certain
time, it may prompt the DF-Series heater to operate
in high fire. The temperature and timing within the
algorithm that causes the DF-series burner to fire in
high or low fire varies each heat cycle. The
thermostat automatically adjusts the DF-Series
output during each cycle to improve operation
efficiency.
11.2 High/Low Firing Operation
When the thermostat is turned up, the burner will
ignite on low fire. The low fire condition is indicated
by the low fire indicator light on the burner box that
illuminates when the gas valve opens. The high fire
condition is indicated by the high fire indicator light
that will illuminate when the gas valve switches to
high fire.
11.3 Sequence of Operation
1. Turn the thermostat up. When the two-stage
thermostat calls for heat, the ignition module will
energize the blower motor.
2. When the motor approaches nominal running
RPM, the pressure switch closes and activates
the ignition module.
3. The ignition module then opens the two-stage
gas valve for low fire operation and energizes
the spark igniter.
4. When the flame is established, the sparking
sequence ceases. The burner is either operat -
ing at high fire or low fire depending on the load
conditions sensed by the thermostat. If the
burner is on high fire, the high fire indicator light
will illuminate immediately. The low fire indicator
light will illuminate upon ignition and stay ener
-
gized while the burner is operation, regardless
of the firing rate. If the burner is on low fire, only
the low fire indicator light will be illuminated.
5. If the flame is not established during the ignition
sequence, the ignition module closes the gas
valve and purge begins. Module will try 2 addi
-
tional times for ignition (with purge in between).
If ignition is not established, the module will lock
out.
6. If the flame extinguishes during operation, the
ignition module will provide multiple trial
sequence described in step 5. If ignition is not
re-established, the module will lock out.
7. After lockout, control must be reset by turning
down thermostat for five seconds, and then rais -
ing it again to desired temperature, or by discon -
necting power and then reconnecting.
8. When the thermostat is satisfied, all power to
the unit is shut off.
Cut/Pinch Hazard
Wear protective gear
during installation,
operation and service.
Edges are sharp.
WARNING
Failure to follow these instructions can result in death, electric shock, injury or property damage.
Burn Hazard
Allow heater to cool
before service.
Tubing may still be hot
after operation.
Explosion Hazard
Turn off gas supply to
heater before service.
DANGER
Electrical Shock Hazard
Disconnect electric
before service.
Heater must be
connected to a properly
grounded electrical
source.