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We reserve the right to make changes.
Roofmaster STEF and STOF
Servicing
Maintenance
Under normal operating conditions, the power roof
ventilator does not require any maintenance. If the
ventilator is used for extracting air from polluting
environments, such as kitchens, the impeller and the fan
casing must be cleaned to remove impurities, if any,
deposited on their surfaces. All local regulations must
be complied with.
Spark-proof version: the impeller and the motor must
be checked at least once a year to guarantee problem-
free operation.
To clean the fan impeller, casing and duct.
1. Isolate the power roof ventilator from the mains
power supply by opening the safety isolating switch.
2. To facilitate the opening of sizes 5, 6 and 7,
the handles (included in delivery) can be used.
The handles are mounted to the casing as shown
in Figure 6.
3. Back off the arresting screws about 10 mm,
so that the fan section can be raised on its hinges.
The stay rod (1 or 2 stay rods depending on the
size of ventilator) locks the fan section automatically
in the fully open position as shown in Figure 5.
4. Make sure that the stay rod has become locked
properly in the open position and that the mounting
of the ventilator base plate and mounting frame
are in good condition.
5. Clean as required. The sound insulated fan casing
surfaces can also be cleaned since the insulation is
protected by perforated sheet metal.
6. On having completed the servicing work, release
the stay support by depressing the locking lever (see
Figure 5) and lower the fan section back to its
initial position. Re-tighten the arresting screws. The
fan casing can also be cleaned from the top after
opening the top grille.
To change the motor and the fan impeller
1. Isolate the power roof ventilator from the mains
power supply by opening the safety isolating switch.
2. Open the top grille on the power roof ventilator
and remove the panels.
3. Raise the fan section as you do for cleaning, see
items 2 and 3 above.
4. Open the end plate of the fan impeller and prise
the impeller off the motor shaft. Note! It is advisable
to cover the chimney opening before doing
the dismantling, so that parts and tools will not
inadvertently fall down the chimney.
5. Lower the fan section, remove the electrical
cables from the junction box and remove the fan
from its mounting plate.
6. Mount a new motor and fan impeller in the reverse
order.
7. Close the power roof ventilator, start it and listen
making sure that no abnormal sound or vibration is
generated by the power roof ventilator.
Fig. 5
Fig. 6
Locking lever
Stay rod
Fastening screw