Pump speed

[sharpspark]

I'm installing a Halstead Ace high into a small house and, having done all the calcs, the pump pressure head vs flow rate is giving considerably more than is required and it is single speed, not adjustable. I know that the system will be balanced by turning down the lockshield valves so the flow rates should be as designed but is the more powerful pump likely to make the system more noisy? Would an equivalent boiler with an adjustable pump set slower be quieter?

 

[sharpspark]

If it is going to be more noisy, would a bigger bypass help?

 

[AlanE]

Most combi boilers that are fitted with adjustable speed controls according to the manufacturers instructions should be set to 3.

'I know that the system will be balanced by turning down the lockshield valves so the flow rates should be as designed but is the more powerful pump likely to make the system more noisy' But is the boiler noisy??

Instructions for the Ace High state that if thermostatic valves are used one rad should be fitted with lockshield types only. This would imply an external bypass is required although the boiler calaims to be fitted with a bypass.

Alan

 

[sharpspark]

Thanks, I don't know if the boiler's noisy yet as I haven't fitted it. I don't want a lot of noise in the house and I'm trying to think of anything that might affect noise up front - including if fitting a different boiler might be quieter. I will have one non-thermostatic rad or towel rail so it will have an external bypass.

 

[AlanE]

If you are fitting it yourself then I trust it will comply with current building regulations and that if you are not CORGI registered you will apply for building control permission as is required.

Alan

 

[sharpspark]

Yes to all!

 

[ChrisR]

Just put an Ace High in a small flat with very few rads. No pipe noise at all. Most combis have v similar fans and 6metre head pumps so would sound much the same. A combis pump speed HAS to be on max to get the heat transfer to the tap HW.

 

[sharpspark]

Thanks!