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Hi All,
Just in the process of starting to piece back together my house and i think I know the answer but would like to have it confirmed if anyone can help? It comes down to pipe sizes that I will choose for replumbing...
For background info:
- it's a 3 bedroom house, with a basement, one main bathroom on 1st floor and one en-suite in the loft. it's only my partner and our young child here at the moment so it's not like we will have several teenagers wanting simultaneous showers.
- I have a vaillant ecotec plus 832 combi boiler which is 32kw and hot water output is 15.2l/mi, the boiler outlet pipe is 15mm - boiler is on ground floor
- the lead pipe mains has been replaced and i've got 32mm mdpe piped all the way up from the road to the boiler cupboard.
- Mains pressure is 6.5/7 bar but i've got it set to 3.5 Bar with a PRV
- I did a simple test and I can fill a builders bucket (14.5l) in about 24 seconds with cold water so somewhere around 36 l/per minute.
My Question is...With the boiler outlet being 15mm, is there really any point in using any 22mm piping for hot or cold water at all? This 15mm boiler outlet is surely the limiting factor? I appreciate that there's less resistance in a larger diameter of 22mm pipe but I'll end up with a huge dead leg of cold water to lose before the shower gets hot and would likely always end up washing hands/ face with cold water because of impatience for the water to get warm.
My plan was to:
- Run everything in 15mm copper
- bend pipes where i can to give a longer radius wherever possible rather than lots of elbows.
- fit flow limiters on toilets, appliances and basins so that if someone flushes the toilet, dishwasher fills etc, it should still keep the shower running well
Can anyone foresee any issue with this setup, would it be too noisy using just 15mm?
Thanks for reading
Just in the process of starting to piece back together my house and i think I know the answer but would like to have it confirmed if anyone can help? It comes down to pipe sizes that I will choose for replumbing...
For background info:
- it's a 3 bedroom house, with a basement, one main bathroom on 1st floor and one en-suite in the loft. it's only my partner and our young child here at the moment so it's not like we will have several teenagers wanting simultaneous showers.
- I have a vaillant ecotec plus 832 combi boiler which is 32kw and hot water output is 15.2l/mi, the boiler outlet pipe is 15mm - boiler is on ground floor
- the lead pipe mains has been replaced and i've got 32mm mdpe piped all the way up from the road to the boiler cupboard.
- Mains pressure is 6.5/7 bar but i've got it set to 3.5 Bar with a PRV
- I did a simple test and I can fill a builders bucket (14.5l) in about 24 seconds with cold water so somewhere around 36 l/per minute.
My Question is...With the boiler outlet being 15mm, is there really any point in using any 22mm piping for hot or cold water at all? This 15mm boiler outlet is surely the limiting factor? I appreciate that there's less resistance in a larger diameter of 22mm pipe but I'll end up with a huge dead leg of cold water to lose before the shower gets hot and would likely always end up washing hands/ face with cold water because of impatience for the water to get warm.
My plan was to:
- Run everything in 15mm copper
- bend pipes where i can to give a longer radius wherever possible rather than lots of elbows.
- fit flow limiters on toilets, appliances and basins so that if someone flushes the toilet, dishwasher fills etc, it should still keep the shower running well
Can anyone foresee any issue with this setup, would it be too noisy using just 15mm?
Thanks for reading
