Read this string before making any decision...
http://forums.moneysavingexpert.com/showthread.html?t=1324209
Also details on 2 different Suprima 60 boilers below...
Potterton Suprima 60L
Fuel Type	Gas
Boiler Type	Conventional
Method	Non-Condensing
Flue Type	Room-Sealed
Fan	Fan Assisted
Output (kW)	17.6 - 17.6
Manufactured From/To	2001 - current
SAP seasonal efficiency	78.1%
Potterton Suprima 60 HE
Fuel Type	Gas
Boiler Type	Conventional
Method	Condensing
Flue Type	Room-Sealed
Fan	Fan Assisted
Output (kW)	17.72 - 17.72
Manufactured From/To	2004 - current
SAP seasonal efficiency	86.2%
                
 Peccavi
                
 March 2009