Riello PRESS 300 T/N ECO Montage- Und Bedienungsanleitung Seite 55

Replacing the minimum
thermostats.
Reposition the probes of the new thermostat, after having
first loosened the plate pack securing screws. Make sure that
the probe is touching the resistor and the plate pack as
shown in the adjacent figure.
The same precautions should be taken when renewing the
resistors in contact with the thermostat probes.
If the pre-heater should malfunction, use an ohmmeter to
check that the resistors located in contact with the tempera-
ture probes are not burnt out (reading of approximately
35 Ohm).
Changing the PT 100 probe in the oil delivery manifold.
Fit the supplied nut and bitapered collar on the new probe, in-
sert a length of approximately 40mm in the manifold, and se-
cure firmly into place. At this point, the section remaining
outside the manifold can be bent as required, with no risk of
damaging the resistor.
4.7 BURNER START-UP PROGRAMME
Normal
Thermostat
Motors
Ignition transformer
Pre-purge
st
1 flame valve
nd
2 flame valve
rd
3 flame valve
Lock-out indicator
(t ) Factory setting: 20 s.
x
This time determines the fuel oil tempera-
ture at ignition. It can be adjusted, accord-
ing to the fuel's viscosity, by the timer 25)
(Fig. 1). The adjacent diagram shows the
suggested settings.
t max = 60 s
x
Motor lock-out
This caused by the overload cutout thermal relay in
the case of overload or absence of phase.
NB.: Periodically clean the filter of the pre-heater
tank.
5841
and maximum temperature
Plate
D2751
Lock-out because no ignition
11
GB
Tubes into aluminium plate
Resistor
Thermostat probe
D2748
D3211
Viscosity at 50°C (°E)