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 ??

[ThomasSiefert · Accepted solution]

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 · Accepted solution]

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

[mohamed_morsi · Accepted solution]

yes it opens manually with no issue 

[mohamed_morsi · Accepted solution]

The voltage at the valve actuator is ok. 

[mohamed_morsi · Accepted solution]

yes, it opens manually. without any problem  

[Aaftab · Accepted solution]

Hi Mohamed,

The issue with valve not opening when the pump flow is running might be due to pressure drop across the valve. The Max Close-off pressure of VF208W 200NS with MF40 is 300Kpa. Additionally, can you please let us know the pipe size and design pressure drop across the valve. 
Thank you!