Vitocal 200-S very slow to power on

[Jonathan2]

Hello Viessmann Community!

I have a Vitocal 200-S, installed in 2013. Occasionally I have needed to switch the unit off using the power switch on the indoor unit.

When switching it back on again, the progress bar on the screen starts moving, the letters HWQC are displayed beneath it, the secondary pump starts and I can hear some relays activate. Then the pump switches off immediately and the progress bar starts again from 0.

This process continues repeatedly for about 15  - 20 minutes and the unit then starts working. 

I would like to know if this is normal behaviour or if it's something that needs fixing. What does HWQC mean?

Thanks for your help!

Jonathan.

[Flo_Schneider]

Hello Jonathan,

the behavior of the controller is definitely not normal. The system usually starts after the bar has run through once. There may either be a contact problem with the control unit or possibly a defect in the control unit. It is best to have this checked by your specialist company.

Best regards
Flo