Bedienungsanleitung Steuerung S4_2006_09_25-neu.doc
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Month of issue xx/2007
Art. No. 950 281
switches the Waterplus appliance off as soon as the set maximum room temperature has been
reached. This will reliably prevent the room of installation from overheating. In this case the
energy needed for the other rooms or for heating drinking water must be generated from
additional heat sources. This is usually achieved by means of a cascade connection with an
electric immersion heater or a oil or gas boiler. Then the auxiliary heat generator only starts up
automatically when the boiler of the Waterplus appliance is switched off. This means that the
base load is still borne by the boiler of the Waterplus appliance, while the other heat generators
only serve to meet demand peaks.
2.3 Minimum operating time / External controller settings
Pellets are a solid fuel which inherently require more time to ignite than do liquid or gaseous
fuels. After the start of ignition it can take a few minutes for the first flame to appear, and a total
of 15 minutes before the preheating programme is completed and the appliance has reached
its full thermal output. In contrast to oil or gas fuelled stoves it can also take a few minutes
after switching off the appliance until all the pellets in the burner pot have burnt down
and the flame goes out. This is why the fan of the appliance has been programmed to
continue running for several minutes after switching off the stove (display shows “G OFF”). You
should therefore wait until this fan after-run time is over before restarting the appliance.
When used with an external controller the appliance should therefore be allowed to run for a
minimum operating time of 30 or better still 60 minutes. This means that the controller must
be set in such a way that the stove’s operating (on-off) cycle does not become too short,
and its hysteresis should be sufficiently large to allow at least 15 minutes to pass from the
“off” to the “restart” signal to accommodate the fan after-run time.
2.4 Heat delivery to water with Waterplus appliances
The heat delivery to water during the operation of Waterplus appliances must be >1.6 kW at
minimum, since otherwise the installed safety devices will make the appliance go into
modulation mode or switch off. Typical signs of insufficient heat delivery to the water heating
system are modulation mode (indicated by “H.M” on the display), frequent switching between on
and off (accompanied by the message “TW OFF” on the display) or an error shutdown triggered
by the temperature cutoff (STB), (indicated by the message “ST”). This shows the importance of
thorough planning to ensure that the appliance is properly connected to the domestic water
system and its control system is properly configurated. The appliance must have a
continuous water throughflow of > 600 l/h, and the circulation pump and the length and flow
resistance of the connecting lines must be dimensioned accordingly. At a flow rate of 600 l/h the
appliance itself has a flow resistance of 130-140 mbar. Insufficient heat delivery to water
points to a problem with the hydraulic system, not with the appliance!
2.5 Room and ambient temperature and humidity during operation
All wodtke appliances are designed only for operation in rooms at normal humidity and at
room temperatures between +5 °C and +25 °C (ambient temperature during operation). At
higher temperatures it can happen that safety devices intervene in the stove’s operation, while
for operation at lower temperatures its settings will need to be adjusted. Please observe the
notes on stove operation concerning this point.
Note: Waterplus appliances require a suitable anti-freeze agent (compatible with solar
energy plants) if they are to be operated at room temperatures <+5°C. wodtke appliances
are generally not splash-proof and must not be installed in wet rooms.
2.6 Connection to chimney
Legal regulations require that pellet stoves be connected to a chimney suitable for solid
fuel fireplaces. The flue gas connector must be made of metal and meet the requirements
of DIN 1298. Your district master chimneysweep will be pleased to advise on this matter. Joint
operation of several appliances via one chimney is admissible, since wodtke stoves fall into
