Diagnosing banging motor valve

[red_rover]

Hi,
I have a three-zone 2016 house with gas heating. When the downstairs heating switches off, it bangs extremely loudly. I have tried adding clips and it only helps to a point, I would have to take down plasterboard to get at the noisest part. The valve appears to be the correct direction. I have a bypass, which seems to be working. I think the bypass pipe is about 15mm. I don't have any TRVs anywhere in the house. Do you think I might need a new valve or perhaps something like an automatic by pass? Thanks a lot.

 

[Timmy D]

If it’s previously worked fine, then something has failed, ergo you shouldn’t need to change piping etc.

Pressure looks a little low, had any issues with losing pressure, needing to top up more regularly?

Expansion vessel possibly lost charge/faulty?

 

[red_rover]

The pressure can be low. It has to be topped up ever year or so, but it always was banging very loudly.

 

[ShaunCorbs]

Open the red wheel head 1/2 a turn the vertical one

 

[red_rover]

Open the red wheel head 1/2 a turn the vertical one

Thanks for this advice. I tried and sadly it didn't work.

 

[ShaunCorbs]

Thanks for this advice. I tried and sadly it didn't work.

Open it more

 

[red_rover]

Open it more

No luck. It is really baffling me

 

[PETE 123]

Zone valve shutting to quick and to much pressure so open gate valve bypass or try turning pump speed down.

 

[Deleted member 120897]

You say the zone valve appears to be fitted the correct way, any proof of this?

 

[red_rover]

Good point. I really don't understand the system so maybe I got that wrong. Here is a picture of the arrow. Is that the only factor to ascertain its direction. Do I need to open it?