ecoTEC plus 937 installation and maintenance manual
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4 on the combi boiler, in parallel to all the other external
heating controllers.
h
Note!
External frost protection devices cannot be
used if plug-in timers are used.
4.23 Heating
pump
The combi boiler is fitted with a heating pump which is
fully wired (additional cabling is not necessary). The
pump has automatic overrun time after the combi boiler
has switched off.
4.24
Anti-cyclic "Economiser" control system
The combi boiler is fitted with an anti-cyclic controller
which ensures that energy wasting short term running
of the combi boiler cannot occur. The controller prevents
the combi boiler from switching on again within a preset
time period after the last switch-off of the central
heating. (Hot water preparation is not affected by this
function. Hot water can be drawn off at any time.)
h
Note!
For temporary cancellation of this switch-on
protection system, turn the main switch ON/
OFF of the combi boiler to position "0" and
then a few seconds later switch to position "l".
4.25
Automatic pump spin control
The combi boiler is fitted with an internal controller
which causes the fitted heating pump to switch on once
in a 23 hour period and also operates the diverter valve.
This controller prevents the jamming up of these
components if the combi boiler is inactive for long
periods. This controller is inactive if the power supply to
the unit is switched off
4 Sequence of operations during installation