VMBGPOx Cooling mode and Pump

With this hot weather and above 23°c, Alarm4 of my VMBGPO (build 1521) switches to “cooling mode” for my heating pump to work inverted. (Alarm 3 switches heating mode bellow 21°c).
At 24°c, the heating pump has to start to refresh my office : the Cooler (CH38) switches ON (“Pressed” status on Velbuslink) but the Pump (CH37) never activates! It has worked last year with this same configuration.
I’ve tried to change to “heating mode” and to ask 28°c and “Heater” switches on and also the Pump after the preset delay of 30".
Velbuslink is V, I’ve tried with 9.82 and 9.78… same problem.
Tried the same senario and configuration on another installation with a VMBGPOD build 1822 and Velbuslink and the problem is the same : no Pump activation!

In Airco mode the pump channel never activates, only the airco channel, that’s how it is conceived.
This happens in the module firmware, Velbuslink has nothing to do with it.
If necessary, you can use the airco channel to double as a pump channel (use it for controlling both the pump and the valve). If you need delays, you can use virtual relays between the airco channel and the output.

After reprogramming the heating pump this winter, I’ve deleted the cooling actions and now, openning an old vlp file, I see that I had a virtual relay coupled to the cooler output to activate the compressor.
Thanks for help, Benoît

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