Butterfly valve canot be opened by actuator

[mohamed_morsi]

Hi Dears 

I had a chiller planet and used BFV with Part number (VF208W-200NS) and actuator (MF40-24F) 

at no load, I send a signal to open the valve and it responds perfectly 

the problem occurs while operating any pump or chiller at planet here the signal can't open the valve.

pipe flow =1450 gpm 

what can I do ??

[Thomas_Siefert]

Have you confirmed that voltage is present at the actuator when trying to open?
If the voltage is present, but is lower than when driving without flow, it could indicate that there is not enough power available.

[MikaelKrantz]

If you try to open it manually, could you do that without force?

[mohamed_morsi]

yes it opens manually with no issue 

[mohamed_morsi]

The voltage at the valve actuator is ok. 

[mohamed_morsi]

yes, it opens manually. without any problem