range rated

[ricky1989]

wonderd if any of you could help got asked a few questions other day which i didnt know so i thought id best follow them up

first said
a central heating boiler is ranged rated to give an output of between 15kw and 20kw briefly explain what information is required to determine which heat output should be selected for a given instalation

any help much appreciated

 

[tamz]

The boiler needs (should be) to be rated to suit the load

 

[ricky1989]

so why does it say
which heat out put would be selected

 

[tamz]

As above it needs to be set to suit the load. Work out the load and set the boiler

The load on the system is the sum of the outputs of the radiators plus an allowance of 2-3kw for the hot water plus 10% for pipe losses.

There are other ways of thinking for this eg whole house.

 

[ricky1989]

im with ya now lol many thankyou

 

[villa_tom]

As above it needs to be set to suit the load. Work out the load and set the boiler

The load on the system is the sum of the outputs of the radiators plus an allowance of 2-3kw for the hot water plus 10% for pipe losses.

There are other ways of thinking for this eg whole house.

My brain just melted

 

[ricky1989]

is that not correct?

 

[villa_tom]

is that not correct?

Yeah its spot on it just reminded me of college!

 

[Reg Man]

History of Range rated: Before the days of electronic modulation and high efficiency; the range rated boilers were great for manufacturers, because they could produce one or two models of boiler which could suit many homes. Remember Baxi bermuda BBU, available in 425 and 552, would suit the majority of 1 to 5 bed homes. Draw back is you have to have an idea of what your demand was likely to be, to be able to set them up for the best efficiency. Right or wrong, I used to use the old Mears mechanical calculator to get an idea on set up and never got any complaints. arrr those were the days.

 

[AWheating]

i looked at my mears calculator the other day and it seemed so strange to see everything in imperial units, cant even think in imperial units now.