domestic boilers

[kev_1911]

hi, could anyone tell me please what is the largest permitted domestic boiler in terms of kw before it changes to commercial sized boilers? ?
thanks.

 

[Terrywookfit]

70Kw input!

 

[Corgigrouch]

Just answered but it seems that I was completely wrong..

 

[WDIK]

now apparently can have to accomodate worcester's a 35mm inlet
how the hell is that domestic?
however thats the case
is there a distinction between domestic and comercial and where will it stop?

acs intructor today asked is there a comercial HE condensing boiler?
answer is yes many but how big are domestics going to get?

 

[Corgigrouch]

I can't think of any normal modern house that would need more than 40Kw to heat it.. My buddy heats his offices and a huge three story farm house off one 40Kw oil boiler... He is also on very good terms with his fuel supplier

If they are rich enough to be able to afford such a large house, then I would recommend two smaller boilers for the convenience of not being without heat if one boiler goes down...More expensive, yes

 

[Doctor Drivel]

70Kw input!

No. Approx 62kW input. 212 cu ft/hr maximum of U6 domestic meter -> 212 * CV (approx 1000) = 212,000 BTU/hr approx. 212000 /3412 = 62.13 kW input. At 90% efficient that is 55.2 output.

Note: the CV varies by location.

A larger U16 meter can be fitted to cope with higher loads. Some say a commercial boiler starts when gas and water pipes get to 35mm.

As flow and return pipes can be reduced in size with larger a delta T, when using a condensing boiler, the main criteria is the gas pipe from the meter.

With a thermal store the boiler may be sized for average use, not peak use. So a 62 kW boiler could heat a house that requires around 70kW input when connected directly to the rads.

 

[Doctor Drivel]

now apparently can have to accomodate worcester's a 35mm inlet

What model?