Computherm Q1RX Operating Instructions Manual page 8

Attention! When reset, both the Off and On delays return to the off
state.
4. DELAY OF THE OUTPUT
When designing heating zones - in order to protect the pumps - it is
advisable to keep at least one heating circuit that is not closed by
a zone valve (e.g. bathroom circuit). If this is not made, in order to
prevent the heating system from an event in which all heating circuits
are closed but a pump is switched on, the socket has two types of
delay function.
Turn on delay
In turned on state, if the output of the socket is switched off, in order
to open the valve(s) of the given heating circuit before starting the
pump, the socket output switches on after a delay of 4 minutes from
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