Vaillant geoTHERM Operating Instructions Manual page 69

In order to prevent a direct changeover between heating
and cooling that does not make sense from an energy point
of view, the transition always takes place via an intervening
period in stand-by.
For the transition:
Heating Stand-by Cooling
the stand-by period is at least six hours. The conditions for
heating (= outside temperature continuously below the pre-
settable max limit outs.temp.) must not be present during
this stand-by period.
For the transition:
Cooling Stand-by Heating
the condition for heating must already have been present
continuously for six hours. Following that there is a stand-
by period of at least six hours during which the condition
for heating must also be present continuously, before the
switchover to heating mode occurs.
This yields the overall conditions for the defined transitions:
For the transitions:
Heating Stand-by Heating
Cooling Stand-by Cooling
the minimum times for the outside temperature with
respect to the max limit outs.temp. are not taken into con-
sideration.
Operating instructions geoTHERM 0020051578_03
Unit function and design
GB
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