Whooshing noise in radiators

[Caws]

My family think I'm mad because I can hear the water rushing through the radiators when the heating is on. They all say it's normal but I'm sure it didn't always sound like this.
I searched through some old posts but the answers didn't make much sense to me.
We have a combi boiler (not sure of make, will check when I go upstairs).
Do the radiators need bleeding? I've never done it as they're all really hot.

 

[muggles]

Common problem with the older / more basic combi boilers - their pumps run too fast for the heating system, so the velocity of water through pipes and valves is too high, resulting in noise. More advanced boilers can have their pump speeds adjusted. Let us know what you have and we can advise

 

[Caws]

Worcester Greenstar compact condensing

 

[muggles]

Well in that case for starters you should turn your boiler thermostat down a bit - running your radiators "really hot" is inefficient and actually prevents your boiler from condensing, which uses more gas. Boilers only condense when the water going back to them from the radiators is below 52°C.

As for the noise issue, your boiler has four different pump settings, so it should be adjusted to best suit the system

 

[Caws]

Is it something I could adjust myself or do I need an engineer to do it?

 

[johnny2007]

Not a plumber, but when i balanced my system i had to almost close the lockshield on the towel rail closest to the boiler and this made that water flowing noise.
Opening it a little tiny more cured the problem.
Something to try.

 

[muggles]

Is it something I could adjust myself or do I need an engineer to do it?

You can do it yourself - instructions are in the manual

 

[Caws]

Will have a search for the manual online - the paper one went missing

 

[Caws]

Not a plumber, but when i balanced my system i had to almost close the lockshield on the towel rail closest to the boiler and this made that water flowing noise.
Opening it a little tiny more cured the problem.
Something to try.

What is a lockshield?

 

[Caws]

So I need to set the radiator temp to less than 52°?

 

[Caws]

Had a look in the manual but can't find anything about pump settings.

 

[johnny2007]

What is a lockshield?

The radiator valve opposite the thermostatic valve.

 

[muggles]

https://tinyurl.com/yc8lf8jd

From Page 14...

"The pump map can be selected within 2.1C in the Boiler settings menu
list:
• 0 (pump variable speed setting)
• 1 (constant pressure low)
• 2 (constant pressure low/middle)
• 3 (constant pressure middle/high)
• 4 (constant pressure high)"

You should have your boiler set to max 70°C (which is the flow temperature) to achieve a target 50°C return, assuming your system is correctly balanced and the pump is set correctly. Go lower if you can, but obviously the house still needs to get warm

 

[Caws]

It's always been on 55°.

 

[Caws]

https://tinyurl.com/yc8lf8jd

From Page 14...

"The pump map can be selected within 2.1C in the Boiler settings menu
list:
• 0 (pump variable speed setting)
• 1 (constant pressure low)
• 2 (constant pressure low/middle)
• 3 (constant pressure middle/high)
• 4 (constant pressure high)"

You should have your boiler set to max 70°C (which is the flow temperature) to achieve a target 50°C return, assuming your system is correctly balanced and the pump is set correctly. Go lower if you can, but obviously the house still needs to get warm

Ah that's different to the manual I downloaded. I must have the wrong one. How do I change the pump settings? (forgive my ignorance - we've never had a combi boiler before so I just leave it on the settings the engineers sets it to when he services it).