Boilers

[hughbyrne]

Hi, Im doing a building energy rating on a building and need to find if a boiler has a fanned flue or not. will it allways be displayed or is there any easy way of telling.

The boiler in question is a Baxi Solo WM 30/4 RS. GC no is 41 077 047

Any help appreciated

 

[bengasman]

What on earth could be the importance of balanced or fanned flue on an energy rating?

 

[namsag]

Fan flue will have a 4inch(ish) usually round terminal balanced flue will have a 9 inch plus square flue.....
Also model number is followed by a couple of letters usually containing an F for fan flue

Balanced flue usually has RS/BF after model

 

[hughbyrne]

Great thanks for your help. Its because the boiler is old I need to work on default values, balance flue and fanned flu have different default efficiency values

 

[fatplumber]

You can check the SEDBUCK rating of the boiler. This is the only real measure. Look here for up to date database. http://www.sedbuk.com

 

[D_Hailsham]

It does not have a fan.

What on earth could be the importance of balanced or fanned flue on an energy rating?

A bit of light reading or a cure for insomnia

 

[bengasman]

It does not have a fan.

What on earth could be the importance of balanced or fanned flue on an energy rating?

A bit of light reading or a cure for insomnia

Would be more accurate just getting the figure for the specific boiler

 

[D_Hailsham]

Would be more accurate just getting the figure for the specific boiler

Agreed. But very old boilers, before Sedbuk efficiency rating were introduced, are just given estimated SAP ratings. These are shown in the Sedbuk datbase with an X in the rating column. The rating can be as low as 55%.

Where the Sedbuk rating has not been measured, it is estimated using the data in Table 4b of the Manual.

 

[bengasman]

Would it be fair to say that about 99% of the aforementioned "very old boilers" are invariably band d or even worse? I know steamers were around before british gas was born, but do you actually find very old domestic boilers in this country that are reasonable in terms of efficiency?

 

[D_Hailsham]

Would it be fair to say that about 99% of the aforementioned "very old boilers" are invariably band d or even worse?

There are a few X marked boilers which would fall in the C band. Most of them fall in the F band or lower; i.e below 74%. The majority are in the G band, below 72%. The problem is that these boilers were never tested, just given a notional efficiency depending on their construction. Sedbuk rating was introduced in 1998.