Heating Operation; Setting The Flow Temperature; Switching Heating Mode Off (Summer Mode); Setting A Room Thermostat Or Weather Compensator - Vaillant ecoTEC plus 937 Operating Manual

4 Operation
4.5

Heating operation

The boiler can only be used if the heating system has
water in it (see Section 4.2.2).
4.5.1

Setting the flow temperature

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Fig. 4.11 Setting the flow temperature
Set the flow temperature by using the knob (1).
We recommend the following settings:
– Left-hand setting
– Mid-position setting in reasonably cold weather
– Right-hand setting
The set value is shown in the display (2) during the set-
ting process. After approx. 3 seconds the display returns
to standard mode (the current heating flow tempera-
ture).
Normally you can adjust the knob (1) continuously up to
a flow temperature of 75 °C.
However, if higher temperatures are required this can be
achieved by adjusting the boiler parameter d.71 (a quali-
fied installer should make this change) up to a maximum
of 85 °C.

4.5.2 Switching heating mode off (summer mode)

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Fig. 4.12 Switching off heating (summer operation)
You can switch off the heating in summer without swit-
ching off the hot water supply.
• Turn the rotary knob (1) for setting the heating flow
temperature all the way to the left.
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in Spring and Autumn,
in very cold weather
4.5.3 Setting a room thermostat or weather com-
pensator
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Fig.4.13 Setting a room thermostat or weather compensator
• Adjust the room thermostat (1) and/or the radiator
thermostatic valves (2) in accordance with the opera-
ting instructions for these accessories.
h Note
Vaillant supplies thermostats and time control-
lers which provide exact and economic room
temperature regulation for improved operating
convenience.
The boiler thus operates automatically according to the
set parameters for the heating system (the ecoTEC com-
bination boiler also provides hot water if required).
After operation is stopped the pump runs on for a short
period to allow the heat to be completely dissipated
from the unit.
h Note
The boiler is fitted with a control unit which
prevents unnecessary and energy-wasting
short-term switching on and off. For this reason
there may be a slight delay when setting a hig-
her temperature on the thermostat before the
boiler switches on.
4.6 Status displays (for maintenance and servi-
cing by the engineer)
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1
Fig. 4.14 Status displays
Operating instructions ecoTEC plus 937 / 0020031573_02
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