Which 50kW boiler?

[bobby62]

In that case I would expect heat loss to be close to 36 kW based on our easy assessment of 1 kW per rad.

With five people a 300 li cylinder would normally suffice.

Visitors dont always use water at same time and plenty of time during the day to reheat!

Dont forgt the CH only needs the calculated power when its -1° C outside! Thats only a few days a year!

Over sizing a boiler is very inefficient and causes on/off cycling because most boilers only have a turn down ratio of 3:1

Tony

Thanks Tony

 

[Biggles..]

Toby... Do you honestly believe all you've just writer

6 showers @ 20lpm
Based on 66/33 hot to cold that's 80lpm

300 litres is 4 minutes of showering then full reheat.

A modern 300litre cylinder normally had a coil of 20+ KWs.

Part l of the building regs.... Cylinder must be reheated in 30 mins! 2kws,3kw or even 6 ,going to do that?

 

[bobby62]

Toby... Do you honestly believe all you've just writer

6 showers @ 20lpm
Based on 66/33 hot to cold that's 80lpm

300 litres is 4 minutes of showering then full reheat.

A modern 300litre cylinder normally had a coil of 20+ KWs.

Part l of the building regs.... Cylinder must be reheated in 30 mins! 2kws,3kw or even 6 ,going to do that?

I was not aware of this reheat time regulation under Part L, could you show where it says that!?

 

[bobby62]

Toby... Do you honestly believe all you've just writer

6 showers @ 20lpm
Based on 66/33 hot to cold that's 80lpm

300 litres is 4 minutes of showering then full reheat.

A modern 300litre cylinder normally had a coil of 20+ KWs.

Part l of the building regs.... Cylinder must be reheated in 30 mins! 2kws,3kw or even 6 ,going to do that?

Are you suggesting a separate 20kW boiler for every installation now in order to achieve a minimum 30min reheat time, surely not. You won't win any jobs that way!

 

[Biggles..]

No but as you've been told previous by another post Hot water priority!

 

[Biggles..]

My mistake it's 60mins but the manufacturers attempt to achieve it in under 30.

 

[Vic Watson]

Hi , I have extended my house , part stone filled walls 120 yrs old plus and new build with modern construction . 2 bedroom, 2 ensuite with one ,possibly two baths and one shower, small utility and small office old house, no insulation in this part, new bit has kitchen 6.5 X 4 meters living room 4x4 meters 2 bedrooms one shower room , hallway ,landing. Approx 13 rads .
My Brother has said I need a massive boiler with expansion vessel as a 40 kW is not enough, I don't see this Any advice out there . Cheers Vic

 

[Dan Robinson]

What does he do for a living?

 

[bernardgreen]

Part l of the building regs.... Cylinder must be reheated in 30 mins! 2kws,3kw or even 6 ,going to do that?

My mistake it's 60mins but the manufacturers attempt to achieve it in under 30.

Is that 60 mins mentioned in Part L ? If so will you say where this requirement is stated in the Part L approved document.

 

[Agile]

What does he do for a living?

Sounds as if he is a builder!

 

[Vic Watson]

Sounds as if he is a builder!

Hi . He is an retired heating engineer