Designing a new hw/ch system

[virgilns]

Y9ou rpropperty is a bit bigger than mine and you seem to like a shower room or 5, but essentially, I have 32mm MDPE mains (moled in like you are suggesting - make sure they keep it 32mm all the way for best results as my guy s wanted to tail it off at 25mm as it was easier!) I then go to 28mm copper to the 250 litre unvented Telford tempest tank)

I had 8bar static presure and a flowe rate more than adequate on the old lead pipe, so my new 'drain pipe' mains shoudl cope cope ok

Shower (only on so far, but planning max of 4) is great bordering on painfull if on full

Sounds like you might have rubish plumbing to the tank or from the tank to the showers...and maybe your boiler is not heating enough of the thermal store?

 

[indus]

Thanks Virgil, I'll make sure they run 32mm all the way.

I may well have 'rubbish plumbing' but I don't think the boiler is the issue. Either way all the plumbing will be changed and the thermal store binned for an unvented system.

I'm pretty sure I'll go for two unvented cylinders but the flow rate after the pipe upgrade will reveal whether I need somw sort of cold storage ie accumulators or break tank.

Have a good weekend

 

[indus]

Thanks Virgil, I'll make sure they run 32mm all the way.

I may well have 'rubbish plumbing' but I don't think the boiler is the issue. Either way all the plumbing will be changed and the thermal store binned for an unvented system.

I'm pretty sure I'll go for two unvented cylinders but the flow rate after the pipe upgrade will reveal whether I need somw sort of cold storage ie accumulators or break tank.

Have a good weekend

 

[indus]

Thanks Virgil, I'll make sure they run 32mm all the way.

I may well have 'rubbish plumbing' but I don't think the boiler is the issue. Either way all the plumbing will be changed and the thermal store binned for an unvented system.

I'm pretty sure I'll go for two unvented cylinders but the flow rate after the pipe upgrade will reveal whether I need somw sort of cold storage ie accumulators or break tank.

Have a good weekend

 

[indus]

Given that I have 19l/min at 3 bar with 22mm pipe is there any way of theoretically calculating what the flow rate will increase to when it is replaced with 32mm pipe?

Thanks

 

[dcawkwell]

Given that I have 19l/min at 3 bar with 22mm pipe is there any way of theoretically calculating what the flow rate will increase to when it is replaced with 32mm pipe?

Thanks

At 22mm pipe you have an area of approx 380mm2

With 32mm pipe you have an area of approx 804mm2

Ratio of 2.11

So 19litre/minute becomes 40litres per minute assuming the pressure is remaining the same.

 

[indus]

Given that I have 19l/min at 3 bar with 22mm pipe is there any way of theoretically calculating what the flow rate will increase to when it is replaced with 32mm pipe?

Thanks

At 22mm pipe you have an area of approx 380mm2

With 32mm pipe you have an area of approx 804mm2

Ratio of 2.11

So 19litre/minute becomes 40litres per minute assuming the pressure is remaining the same.

Thanks. That's very good news and may mean I don't need large cold water storage.