Noise on the pipe when heating goes on and off. Help

[Jonny Vee]

A year ago I got house completely re plumbed with new pipe and heating system.

I got system boiler with unvented cylinder. Issue is when heating goes on and when goes of we can hear a very noise on some pipe like TRRRRRR DUDUDUDU ( not easy to explain) This was noted t the plumber last year and he reduced the pressure next to the cylinder and all was good for a while. Turned heating on this year and noise is back. pressure is already to 0.1 and can`t adjust lower than that. Does anyone knows what`s wrong?

Thanks

 

[cross thread]

Are the zone valves the correct way round,normally have a flow direction arrow

 

[Jonny Vee]

Are the zone valves the correct way round,normally have a flow direction arrow

Not sure but if they wee wrong way round I assume the heating would not work or still work?

 

[cross thread]

Still work but can cause noise

 

[BlueLoo]

I'm struggling with the pressure bit.
what pressure? (System?)
0.1bar?

Can you post a pic of the valve you are twiddling with?
Are you sure you've got this right? Should it not be system pressure, 1.0 bar?
You could be starving the system which is causing low flow as per your other thread.

 

[Jonny Vee]

I'm struggling with the pressure bit.
what pressure? (System?)
0.1bar?

Can you post a pic of the valve you are twiddling with?
Are you sure you've got this right? Should it not be system pressure, 1.0 bar?
You could be starving the system which is causing low flow as per your other thread.

 

[ianmcd]

That is an automatic By-Pass put it back to what it was origionally set at and leave it alone, it has nothing to do with your sytem pressure

 

[BlueLoo]

A bypass valve set to min may be open more than not. This could explain the lack of heat input to the HW tank in the other thread.

 

[Jonny Vee]

A bypass valve set to min may be open more than not. This could explain the lack of heat input to the HW tank in the other thread.

Plumber put it to that minimum saying noise in the pipe will disappear

 

[CBW]

Post photos of valves, if you don’t know if installed correct way around

 

[BlueLoo]

Plumber put it to that minimum saying noise in the pipe will disappear

Sounds like ******. The data sheet (myson) tells you to turn it down if noisy but then again, myson would assume your system is designed and set up well.

What is your pump set at? Can you take a photo of it?

 

[Jonny Vee]

Sounds like ******. The data sheet (myson) tells you to turn it down if noisy but then again, myson would assume your system is designed and set up well.

What is your pump set at? Can you take a photo of it?

There is no external pump unless you mean one the cylinder or boiler. Boiler is an Atag system boiler i40s

 

[BlueLoo]

There is no external pump unless you mean one the cylinder or boiler. Boiler is an Atag system boiler i40s

I am at the limit of my understanding here so better comments may come from the pro's on the site.

If the system is run of a ErP pump, then that is perhaps a variable speed pump and probably working on a DP or CP basis which makes the automatic bypass valve you are fiddling with utterly useless. I dunno about the boiler, but if it has its own internal bypass, then you don't want a ABV at all as it will just cycle the boiler outlet through the boiler without distributing heat anywhere else? (Probs why the plumber had this at MAX).

Is this the same plumber who installed it who told you to turn it down to min?

I think you need a decent heating engineer to take a look and set up your system correctly for you.

Edit: no mention of a bypass required in the boiler manual.

Strange set up....

 

[ianmcd]

which makes the automatic bypass valve you are fiddling with utterly useless. I dunno about the boiler, but if it has its own internal bypass, then you don't want a ABV at all as it will just cycle the boiler outlet through the boiler without distributing heat anywhere else? (Probs why the plumber had this at

it is on an S Plan so an ABV is required

 

[Mottie]

My hot water is on 24/7 and every night after I had had my shower and got into bed, about 15 minutes later there was a single bang/thump on the system like someone had bashed a pipe with a hammer. Took me weeks to find out what it was and it turned out to be the ABV opening - I confirmed it by holding on to the thing and waited for the bang - I could clearly feel it too. That was on my old boiler when I had no inhibitor in the system. I don't know if inhibitor has lubricating properties but when I added it to the system, the noise disappeared so I assume it was just slightly sticky?