Pump speed temperature issues

[monty9120]

What pump speed is perfect for a Worcester Bosch 28 junior combi? I read it must be on 3 but I've turned it down and can't tell any difference?

In the cold weather if I set the temp at 19 it gets there easy and doesn't fire that much

If I set it higher then 21 it struggles but the return temp hovers around the 55 degrees this is with the boiler on temp 5 out of 7 if I go higher it won't condense I suppose as the returns higher then 55 degrees

Systems all been sorted and flushed radiators are roasting

An I just asking too much

 

[ScottishGasMan]

The junior green star if I'm right requires you to disturb the sealed outer casing to access the pump, which you shouldn't be doing on the grounds of safety so only advice is not to touch it and ideally get someone qualified and experienced to check its fitted correctly,


Ps. If it's says it must be on setting three then it must be on setting three, it's actually that simple

 

[Steelmasons]

I guess maintaining efficiency requires the use of a woolly jumper and/or an overcoat.

 

[monty9120]

No where on line says what speed it should be on that's why I asked

You can reach the toggle on the pump without disturbing anuthing

 

[ScottishGasMan]

I read it must be on 3

where did you read it then?

 

[simond]

Speed 3 is to enable the HW to work efficiently. At lower speeds the boiler water won't pass through the plate fast enough for optimum heat transfer into the mains cold water.

And if it's a Greenstar iJunior, you have removed the case seal. And knobbled the HW performance by the sound of it.

 

[monty9120]

I just saw the info from a website with a boiler engineer I presume no concrete guide as such

I haven't touched the case on the boiler so unsure what you mean