Radiators not heating , poor circulation?

[Terry lambert]

@D_Hailsham

Yes I have read it and as I understood it.

The Taco setters are not cheap, I don’t think I have ever seen one in a domestic set up which is why I suggested setting it to the ABV to the required flow rate and pressure setting and then tweaking if there was undue noise.

I tell a lie, BG used to fit taco flow setters as standard for bypasses many moons ago

I’ll give it some thought

 

[D_Hailsham]

There's one going for £10 + £5 deliver on ebay at the moment. It covers the OP's requirements, but I'm not sure if it's 15mm or 22mm.

I searched for prices and they seem be £50 and upwards.

 

[Terry lambert]

Yes, I’ve looked at them before and £50 - £80 seems about right

 

[dilalio]

1 pill to make you small... and 1 to make you large again!

 

[Terry lambert]

There's one going for £10 + £5 deliver on ebay at the moment. It covers the OP's requirements, but I'm not sure if it's 15mm or 22mm.

I searched for prices and they seem be £50 and upwards.

just to be doubly sure I ran through the scenario on another forum of engineers, if the pump is set to constant pressure the auto bypass should be set to the minimum flow rate of the boiler and pump setting, no flow setter required

 

[D_Hailsham]

just to be doubly sure I ran through the scenario on another forum of engineers, if the pump is set to constant pressure the auto bypass should be set to the minimum flow rate of the boiler and pump setting, no flow setter required

I have found the instructions for the OP's bypass valve and have plotted the requirements on it: Flow 4.5 litre/min = 270 litres/hr; Pump setting CP1 = 30kPa = 0.3 bar. This shows that the bypass has to be set somewhere between 0.2 and 0.3, but where exactly? At 0.2 the flow will be too great; at 0.3 there will be no flow? How can you accurately set the valve without a flow meter?

 

[Terry lambert]

The engineers I asked are far more knowledgeable than me and want to know the ins and outs of a ducks bottom. They say do not need a flow setter, just set to minimum flow of boiler, how you get to that I suppose is our problem. They most certainly know their stuff


As I said before I don’t like either scenario.

So one of the jobs I’m fitting next week is an Intergas 40KW system boiler, it has no internal bypass and a burner linked pump (similar to proportional ) on an S plan

I’ve been giving my self a headache all day trying to figure out the best way to configure this, I could fit a manual bypass or a flow setter

Both will be inefficient

I might pipe it as hot water priority so always open to heating when a demand ends or I could fit a three port to be open to the return a bit like a motorised bypass so that I don’t waste energy and lose efficiency

I’m looking at this I’m depth at the moment with different boilers how they control the pump, what you can tweak in parameters

It’s a nuisance, give me back fixed head