I have 7 radiators running off my bosch 28i junior and i'm doing a loft conversion and want to add 2 small radiators.Don't know if my boiler can cope with this.

stephen, June 2009

I have 8 radiators running off my 28i Junior with no problems. P.S the 28i junior is 90.2% efficient, not 79% as stated above

Daren, February 2010

My boiler is 29.3kW and drives 16 radiators ok in a 10 room house and a big hot water tank.

Your boiler is rated at 27.5kW...

My boiler is conventional and 74% efficient
Your boiler is a Combi and 79% efficient

I know precious little about heating but I would guess you will not have a problem - I'm sure there are complicated equations to work the figures through but somehow I don't think you need to.

Peccavi, June 2009