Riello ENNE 1400 Mode D'emploi page 50

SPRAY TEMPERATURE ADJUSTMENT
Electronic adjustment thermostat
By means of information relayed from a PT 100 probe immersed
in the oil in the delivery manifold, the thermostat adjusts spray
temperature. (The correct conditions for fuel spray are shown in
the temperature/viscosity graph below).
Atomisation temperature
S7976
∆t Pre-heater - Delivery
Example: fuel oil with 7° E viscosity at 50° C is pre-heated to ap-
proximately 110° C.
Important:
although the temperature set on the thermostat should corre-
spond to the temperature of the fluid, it is good practice to check
that the thermometer shows the correct reading once the unit has
been in operation for a few minutes. The led will illuminate to in-
dicate that the heating resistances are working properly.
Important , only for N/M 4500.
The pre-heater fitted to the burner supplies a ∆t of 75°C at 450
kg/h (right-hand graph).
If there is a ∆t shortfall, this can be made up by an auxiliary pre-
heater.
Minimum temperature thermostat, in addition to shutting down
the burner if the fuel temperature should fall below the critical va-
lue for correct combustion, this thermostat also provides a per-
missive signal at the time of burner start-up. (Factory set at
approximately 80°C, adjustable by removing the pre-heater cover
and relative plate).
Maximum temperature thermostat, this switches off the resi-
stances when, because of failure of the adjustment thermostat,
the temperature of the pre-heater increases to unacceptable le-
vels; a "high temperature" alarm output is provided on the burner
terminal strip. (Factory set is approximately 180°C).
5041
Renewing the minimum and maximum temperature thermo-
stats
Reposition the probe of the new thermostat, after having first lo-
osened the plate pack securing screws. Make sure that the probe
is touching the resistance and the plate pack as shown in the
adjacent figure.
The same precutions should be taken when renewing the resi-
stances in contact with the thermostat probes.
If the pre-heater should malfunction, use an ohmmeter to check
Fig. 18
that the resistances located in contact with the temperature pro-
bes are not burnt out (reading of approximately 35 Ohm).
Aluminium plate
S7977
Changing the PT 100 probe in the oil delivery manifold
Fit the supplied nut and biconical collar on the new probe, insert
a lenght of approximately 40 mm in the manifold, and secure fir-
mly into place.
At this point, the section remaining outside the manifold can be
bent as required (with no risk of damaging the resistance).
12 GB
Adjustment thermostat probe
Thermometer
Min. temperature thermostat
S7972
Pre-heater
Max. temperature thermostat
Purge
Tubes into aluminium plate
Thermostat probe
Fig. 19
Resistance
Fig. 20