How many radiators can the Valiant 428kw run?

[Dan Robinson]

I would consider going up a size.

But if you are warm, and everything works don't panic.

 

[JohnD]

modern pipe lagging is a stiff foam plastic tube, which can be pushed over pipe from the end, or opened up with a pre-made slit to push on from the side (there is a black rubbery version, Armaflex, for wet or underground conditions). The Regs, "Byelaws" grade is as thick as your arm, and the wall thickness is about 20mm (observe this picture, where the hole in the middle is for 22mm pipe).
http://www.wickes.co.uk/Wickes-Pipe-Insulation-Byelaw-22-x-1000mm/p/210013

There are some cheaper own-brands like this. I believe the plastic foam is polythene, it is not soft like a foam mattress and does not squash easily. You can cut or trim it with a serrated knife.

 

[sapphirenick1]

I would consider going up a size.

But if you are warm, and everything works don't panic.

Do you mean the pump, Dan? Do you know what the next one up would be?

 

[sapphirenick1]

modern pipe lagging is a stiff foam plastic tube, which can be pushed over pipe from the end, or opened up with a pre-made slit to push on from the side (there is a black rubbery version, Armaflex, for wet or underground conditions). The Regs, "Byelaws" grade is as thick as your arm, and the wall thickness is about 20mm (observe this picture, where the hole in the middle is for 22mm pipe).
http://www.wickes.co.uk/Wickes-Pipe-Insulation-Byelaw-22-x-1000mm/p/210013

There are some cheaper own-brands like this. I believe the plastic foam is polythene, it is not soft like a foam mattress and does not squash easily. You can cut or trim it with a serrated knife.

Perfect, thank you! The stuff they used is really rather thin - probably 9mm, so I will definitely replace it with the thickest I can.

 

[oph]

If a 428 is being used then the primaries need to be bigger than 22mm and also an effective bypass needs to be thought about....

 

[sapphirenick1]

If a 428 is being used then the primaries need to be bigger than 22mm and also an effective bypass needs to be thought about....

My apologies, I have just been and checked and the Flow/Returns to and from the 428 and cylinders are 28mm. I trust thats okay?

I am not sure about the bypass? What am I looking for there?

 

[D_Hailsham]

Both cylinders are actually heated at the same time - they are connected together to make a total of 290l hot water, they don't supply a different zone, but they each have their own motorised valve.

Is hot water drawn equally from both cylinders when a tap is turned on? If so, they will cool down at the same rate and both need reheating at the same time. Or do you have separate timers for each cylinder so this cannot happen?

My boiler does enter anti-cycling mode when heating the hot water,

All depends on why it has gone into anti-cycling mode

I take it your heating is still on when you heat up the water at 9pm to 12:30am?

Yes. But at that time of night, and even in the afternoon, the boiler only comes on occasionally for the central heating, so most of the boiler's output is directed to the cylinder.

 

[sapphirenick1]

Both cylinders are actually heated at the same time - they are connected together to make a total of 290l hot water, they don't supply a different zone, but they each have their own motorised valve.

Is hot water drawn equally from both cylinders when a tap is turned on? If so, they will cool down at the same rate and both need reheating at the same time. Or do you have separate timers for each cylinder so this cannot happen?

No separate timers for each cylinder. They draw equally, which is fine by me.

My boiler does enter anti-cycling mode when heating the hot water,

All depends on why it has gone into anti-cycling mode

I asked the Valiant engineer why it happens and he said "they do this" - should it definitely not be anti-cycling for any reason?

 

[D_Hailsham]

No separate timers for each cylinder. They draw equally, which is fine by me.
...
I asked the Valiant engineer why it happens and he said "they do this" - should it definitely not be anti-cycling for any reason?

If your happy, that's all that matters.