Listing of current regular boilers for Ideal listed in declining SEDBUK rating order.

Ideal: Icos : HE36
gas : regular : condensing : wall mounted
Power Rating: (37 - 37 kW) SEDBUK efficiency 90.7%

Ideal: Icos : HE30
gas : regular : condensing : wall mounted
Power Rating: (30.1 - 30.1 kW) SEDBUK efficiency 90.7%

Ideal: Mexico : HE 36
gas : regular : condensing : floor mounted
Power Rating: (37.0 - 37.0 kW) SEDBUK efficiency 90.7%

Ideal: icos : HE15
gas : regular : condensing : wall mounted
Power Rating: (14.6 - 14.6 kW) SEDBUK efficiency 90.4%

Ideal: Maximiser : SE 42
gas : regular : condensing : wall mounted
Power Rating: (40 - 40 kW) SEDBUK efficiency 90.4%

Ideal: Imax : W60
gas : regular : condensing : wall mounted
Power Rating: (60 - 60 kW) SEDBUK efficiency 90.4%

Ideal: icos System : HE 15
gas : regular : condensing : wall mounted
Power Rating: (14.6 - 14.6 kW) SEDBUK efficiency 90.4%

Ideal: Imax : W45
gas : regular : condensing : wall mounted
Power Rating: (45 - 45 kW) SEDBUK efficiency 90.4%

Ideal: Mexico : HE15
gas : regular : condensing : floor mounted
Power Rating: (14.6 - 14.6 kW) SEDBUK efficiency 90.4%

Ideal: Mexico : HE 30
gas : regular : condensing : floor mounted
Power Rating: (30.1 - 30.1 kW) SEDBUK efficiency 90.4%

Evo: HE 16 : HE16
gas : regular : condensing : wall mounted
Power Rating: (14.6 - 14.6 kW) SEDBUK efficiency 90.4%

Evo: HE 19 : HE19
gas : regular : condensing : wall mounted
Power Rating: (18.2 - 18.2 kW) SEDBUK efficiency 90.3%

Ideal: Mexico : HE18
gas : regular : condensing : floor mounted
Power Rating: (18.2 - 18.2 kW) SEDBUK efficiency 90.3%

Evo: HE 12 : HE 12
gas : regular : condensing : wall mounted
Power Rating: (12.7 - 12.7 kW) SEDBUK efficiency 90.3%

Ideal: icos : HE18
gas : regular : condensing : wall mounted
Power Rating: (18.2 - 18.2 kW) SEDBUK efficiency 90.3%

Ideal: Icos : HE 12
gas : regular : condensing : wall mounted
Power Rating: (12.7 - 12.7 kW) SEDBUK efficiency 90.3%

Ideal: Mexico : HE 24
gas : regular : condensing : floor mounted
Power Rating: (23.4 - 23.4 kW) SEDBUK efficiency 90.2%

Ideal: Maximiser : SE 65
gas : regular : condensing : wall mounted
Power Rating: (55.1 - 55.1 kW) SEDBUK efficiency 90.2%

Ideal: icos : HE24
gas : regular : condensing : wall mounted
Power Rating: (23.4 - 23.4 kW) SEDBUK efficiency 90.2%

Ideal: icos System : HE 24
gas : regular : condensing : wall mounted
Power Rating: (23.4 - 23.4 kW) SEDBUK efficiency 90.2%

Evo: HE 22 : HE22
gas : regular : condensing : wall mounted
Power Rating: (23.4 - 23.4 kW) SEDBUK efficiency 90.2%

Ideal: Classic : HE 18
gas : regular : condensing : wall mounted
Power Rating: (18 - 18.0 kW) SEDBUK efficiency 87.5%

Optia: HE 18 :
gas : regular : condensing : wall mounted
Power Rating: (18 - 18.0 kW) SEDBUK efficiency 87.5%

Optia: HE 12 :
gas : regular : condensing : wall mounted
Power Rating: (12 - 12.0 kW) SEDBUK efficiency 87.4%

Ideal: Classic : HE 12
gas : regular : condensing : wall mounted
Power Rating: (12 - 12.0 kW) SEDBUK efficiency 87.4%

Ideal: Classic : HE 9
gas : regular : condensing : wall mounted
Power Rating: (9 - 9.0 kW) SEDBUK efficiency 87.1%

Optia: HE 9 :
gas : regular : condensing : wall mounted
Power Rating: 9.0 kW SEDBUK efficiency 87.1%

Optia: HE 15 :
gas : regular : condensing : wall mounted
Power Rating: (15 - 15.0 kW) SEDBUK efficiency 86.4%

Ideal: Classic : HE 15
gas : regular : condensing : wall mounted
Power Rating: (15 - 15.0 kW) SEDBUK efficiency 86.4%

Ideal: Concord : CXC48
gas : regular : condensing : floor mounted
Power Rating: (48.83 - 48.83 kW) SEDBUK efficiency 85.8%

Ideal: Concord : CXC70
gas : regular : condensing : floor mounted
Power Rating: (69.84 - 69.84 kW) SEDBUK efficiency 85.5%

Ideal: Concord CXSD : 40/H
gas : regular : non condensing : floor mounted
Power Rating: (43.5 - 43.5 kW) SEDBUK efficiency 80.4%

Ideal: Concord CXS : 40/H
gas : regular : non condensing : floor mounted
Power Rating: (43.5 - 43.5 kW) SEDBUK efficiency 80.4%

Ideal: Concord CXS : 60/H
gas : regular : non condensing : floor mounted
Power Rating: (65.2 - 65.2 kW) SEDBUK efficiency 80.3%

Ideal: Concord CXSD : 60/H
gas : regular : non condensing : floor mounted
Power Rating: (65.2 - 65.2 kW) SEDBUK efficiency 80.3%

Ideal: Concord CXS : 50/H
gas : regular : non condensing : floor mounted
Power Rating: (54.3 - 54.3 kW) SEDBUK efficiency 80.1%

Ideal: Concord CXSD : 50/H
gas : regular : non condensing : floor mounted
Power Rating: (54.3 - 54.3 kW) SEDBUK efficiency 80.1%

Ideal: Classic Slimline : SE9 FF
gas : regular : non condensing : wall mounted
Power Rating: 8.8 kW SEDBUK efficiency 79.9%

Ideal: Classic : SE15 RS
gas : regular : non condensing : wall mounted
Power Rating: 14.7 kW SEDBUK efficiency 79.9%

Ideal: Concord CXA : 40/H
gas : regular : non condensing : floor mounted
Power Rating: 43.5 kW SEDBUK efficiency 79.9%

Ideal: Mexico Super : 470 FF
gas : regular : non condensing : floor mounted
Power Rating: 20.5 kW SEDBUK efficiency 79.9%

Ideal: Concord CXA : 50/H
gas : regular : non condensing : floor mounted
Power Rating: 54.3 kW SEDBUK efficiency 79.9%

Ideal: Classic Slimline : SE15 FF
gas : regular : non condensing : wall mounted
Power Rating: 14.7 kW SEDBUK efficiency 79.9%

Ideal: Concord CXA : 60/H
gas : regular : non condensing : floor mounted
Power Rating: 65.2 kW SEDBUK efficiency 79.8%

Ideal: Mexico Super : CF 465
gas : regular : non condensing : floor mounted
Power Rating: 19.1 kW SEDBUK efficiency 79.7%

Ideal: Mexico Super : 480 FF
gas : regular : non condensing : floor mounted
Power Rating: 23.4 kW SEDBUK efficiency 79.7%

Ideal: Classic Slimline : SE18 FF
gas : regular : non condensing : wall mounted
Power Rating: 17.6 kW SEDBUK efficiency 79.7%

Ideal: Classic : SE15 FF
gas : regular : non condensing : wall mounted
Power Rating: 14.7 kW SEDBUK efficiency 79.6%

Optia: FF50 :
gas : regular : non condensing : wall mounted
Power Rating: 14.7 kW SEDBUK efficiency 79.6%

Ideal: Classic : SE15 FF Silver
gas : regular : non condensing : wall mounted
Power Rating: 14.7 kW SEDBUK efficiency 79.6%

Ideal: Mexico Super : 80FF
gas : regular : non condensing : floor mounted
Power Rating: (20.5 - 23.4 kW) SEDBUK efficiency 79.4%

Ideal: Mexico Super : RS 4125
gas : regular : non condensing : floor mounted
Power Rating: 36.6 kW SEDBUK efficiency 79.4%

Ideal: Classic : SE9 FF
gas : regular : non condensing : wall mounted
Power Rating: 8.8 kW SEDBUK efficiency 79.4%

Ideal: Classic : SE9 FF Silver
gas : regular : non condensing : wall mounted
Power Rating: 8.8 kW SEDBUK efficiency 79.4%

Optia: FF30 :
gas : regular : non condensing : wall mounted
Power Rating: 8.8 kW SEDBUK efficiency 79.4%

Ideal: Mexico Super : 460 FF
gas : regular : non condensing : floor mounted
Power Rating: 17.6 kW SEDBUK efficiency 79.2%

Ideal: Classic Slimline : SE12 FF
gas : regular : non condensing : wall mounted
Power Rating: 11.7 kW SEDBUK efficiency 79.2%

Ideal: Classic : FF 360 LF
gas : regular : non condensing : wall mounted
Power Rating: 17.6 kW SEDBUK efficiency 79.1%

Ideal: Classic : FF 340 LF
gas : regular : non condensing : wall mounted
Power Rating: 11.7 kW SEDBUK efficiency 79.1%

Ideal: Mexico Super : RS 450
gas : regular : non condensing : floor mounted
Power Rating: 14.7 kW SEDBUK efficiency 79.1%

Ideal: Mexico Super : RS 485
gas : regular : non condensing : floor mounted
Power Rating: 24.9 kW SEDBUK efficiency 79.1%

Ideal: Mexico Super : 450 FF
gas : regular : non condensing : floor mounted
Power Rating: 14.7 kW SEDBUK efficiency 79.0%

Ideal: Classic : SE18 RS
gas : regular : non condensing : wall mounted
Power Rating: 17.6 kW SEDBUK efficiency 79.0%

Ideal: Mexico Super : RS 470
gas : regular : non condensing : floor mounted
Power Rating: 20.5 kW SEDBUK efficiency 79.0%

Ideal: Mexico Super : CF 4120
gas : regular : non condensing : floor mounted
Power Rating: 35.2 kW SEDBUK efficiency 79.0%

Ideal: Mexico Super : RS 4100
gas : regular : non condensing : floor mounted
Power Rating: 29.3 kW SEDBUK efficiency 79.0%

Ideal: Mexico Super : RS 460
gas : regular : non condensing : floor mounted
Power Rating: 17.6 kW SEDBUK efficiency 79.0%

Ideal: Mexico Super : CF 475
gas : regular : non condensing : floor mounted
Power Rating: (22 - 22.0 kW) SEDBUK efficiency 78.9%

Ideal: Classic : SE12 RS
gas : regular : non condensing : wall mounted
Power Rating: 11.7 kW SEDBUK efficiency 78.9%

Ideal: Mexico Super : 4100 FF
gas : regular : non condensing : floor mounted
Power Rating: 29.3 kW SEDBUK efficiency 78.9%

Ideal: Mexico Super : CF 495
gas : regular : non condensing : floor mounted
Power Rating: 27.8 kW SEDBUK efficiency 78.8%

Ideal: Classic : SE12 FF Silver
gas : regular : non condensing : wall mounted
Power Rating: 11.7 kW SEDBUK efficiency 78.6%

Ideal: Classic : SE12 FF
gas : regular : non condensing : wall mounted
Power Rating: 11.7 kW SEDBUK efficiency 78.6%

Ideal: Mexico Super : RS 440
gas : regular : non condensing : floor mounted
Power Rating: 11.7 kW SEDBUK efficiency 78.6%

Optia: FF40 :
gas : regular : non condensing : wall mounted
Power Rating: 11.7 kW SEDBUK efficiency 78.6%

Ideal: Mexico Super : CF 4140
gas : regular : non condensing : floor mounted
Power Rating: (41 - 41.0 kW) SEDBUK efficiency 78.6%

Ideal: Mexico Super : 4125 FF
gas : regular : non condensing : floor mounted
Power Rating: 36.6 kW SEDBUK efficiency 78.5%

Ideal: Mexico Slimline : CF 440
gas : regular : non condensing : floor mounted
Power Rating: 11.7 kW SEDBUK efficiency 78.5%

Ideal: Mexico Super : CF 445
gas : regular : non condensing : floor mounted
Power Rating: 13.2 kW SEDBUK efficiency 78.5%

Ideal: Mexico Super : CF 455
gas : regular : non condensing : floor mounted
Power Rating: 16.1 kW SEDBUK efficiency 78.5%

Ideal: Classic : SE21 FF
gas : regular : non condensing : wall mounted
Power Rating: 20.5 kW SEDBUK efficiency 78.5%

Ideal: Classic : SE21 FF Silver
gas : regular : non condensing : wall mounted
Power Rating: 20.5 kW SEDBUK efficiency 78.5%

Optia: FF70 :
gas : regular : non condensing : wall mounted
Power Rating: 20.5 kW SEDBUK efficiency 78.5%

Ideal: Mini S28 : 28kW System Boiler
gas : regular : non condensing : wall mounted
Power Rating: (28 - 28 kW) SEDBUK efficiency 78.4%

Ideal: Mexico Slimline : RS 445
gas : regular : non condensing : floor mounted
Power Rating: 13.2 kW SEDBUK efficiency 78.4%

Ideal: Classic : FF 350 LF
gas : regular : non condensing : wall mounted
Power Rating: 14.7 kW SEDBUK efficiency 78.4%

Ideal: Classic : SE9 RS
gas : regular : non condensing : wall mounted
Power Rating: 8.8 kW SEDBUK efficiency 78.3%

Ideal: Classic : SE18 FF Silver
gas : regular : non condensing : wall mounted
Power Rating: 17.6 kW SEDBUK efficiency 78.3%

Ideal: Classic : SE18 FF
gas : regular : non condensing : wall mounted
Power Rating: 17.6 kW SEDBUK efficiency 78.3%

Optia: FF60 :
gas : regular : non condensing : wall mounted
Power Rating: 17.6 kW SEDBUK efficiency 78.3%

Ideal: Mexico Super : 440 FF
gas : regular : non condensing : floor mounted
Power Rating: 11.7 kW SEDBUK efficiency 78.3%

Ideal: Mini S24 : 24kW System Boiler
gas : regular : non condensing : wall mounted
Power Rating: (24.3 - 24.3 kW) SEDBUK efficiency 78.3%

Ideal: Classic : SE24 FF
gas : regular : non condensing : wall mounted
Power Rating: 23.4 kW SEDBUK efficiency 78.1%

Ideal: Classic : SE24 FF Silver
gas : regular : non condensing : wall mounted
Power Rating: 23.4 kW SEDBUK efficiency 78.1%

Optia: FF80 :
gas : regular : non condensing : wall mounted
Power Rating: 23.4 kW SEDBUK efficiency 78.1%

Ideal: Classic : SE30 FF
gas : regular : non condensing : wall mounted
Power Rating: 29.3 kW SEDBUK efficiency 78.0%

Ideal: Classic : SE30 FF Silver
gas : regular : non condensing : wall mounted
Power Rating: 29.3 kW SEDBUK efficiency 78.0%

Optia: FF100 :
gas : regular : non condensing : wall mounted
Power Rating: 29.3 kW SEDBUK efficiency 78.0%

Ideal: Mexico Super : 125FF
gas : regular : non condensing : floor mounted
Power Rating: (29.3 - 36.6 kW) SEDBUK efficiency 77.9%

This information has been collated from Manufacturers literature and the SEDBUK online database as at April 2007.

Small variations in efficiency ratings are not significant. It can be assumed that a 3% difference in rating will give a 95% confidence that the higher rated boiler is more efficient than the lower.