kWh Index

Boilers, ranked by AFUE

645 boilers from 51 brands, collapsed from 650 published configurations. Each priced at the national average rate, so the ranking is what it costs to run rather than what it says on the box.

ModelAFUECosts to run
Energy Kinetics Accel CS EK1C 9097.00$23.95 per million BTU of heat
Velocity Boiler Works RPTR110HB96.00$24.20 per million BTU of heat
Velocity Boiler Works RPTR085HB96.00$24.20 per million BTU of heat
U.S. Boiler Company ASPN-11096.00$24.20 per million BTU of heat
U.S. Boiler Company ASPN-08596.00$24.20 per million BTU of heat
Burnham by U.S. Boiler ASPN-11096.00$24.20 per million BTU of heat
Burnham by U.S. Boiler ASPN-08596.00$24.20 per million BTU of heat
Rinnai IP150S (REB-B4400FFUS)96.00$24.20 per million BTU of heat
Rinnai IP150199C (REB-B4458FF-US)96.00$24.20 per million BTU of heat
Rinnai IP120S (REB-B3500FFUS)96.00$24.20 per million BTU of heat
Rinnai IP120199C (REB-B3558FF-US)96.00$24.20 per million BTU of heat
Rinnai IP090S (REB-B2600FFUS)96.00$24.20 per million BTU of heat
Rinnai IP090199C (REB-B2658FF-US)96.00$24.20 per million BTU of heat
Rinnai IP090160C (REB-B2647FF-US)96.00$24.20 per million BTU of heat
Rinnai IP090099C (REB-B2630FF-US)96.00$24.20 per million BTU of heat
Radiant R2KA 34/2096.00$24.20 per million BTU of heat
Radiant R2KA 24/2096.00$24.20 per million BTU of heat
Radiant R2K 5596.00$24.20 per million BTU of heat
Radiant R2K 3496.00$24.20 per million BTU of heat
Radiant R2K 2496.00$24.20 per million BTU of heat
Radiant R1K 5596.00$24.20 per million BTU of heat
Radiant R1K 34/B96.00$24.20 per million BTU of heat
NTI TRX08596.00$24.20 per million BTU of heat
NTI TFTN08596.00$24.20 per million BTU of heat
NTI NC08596.00$24.20 per million BTU of heat
NTI FTVN08596.00$24.20 per million BTU of heat
HTP ELU-85WBN96.00$24.20 per million BTU of heat
HTP EFTU-85WBN96.00$24.20 per million BTU of heat
Navien NFB700-200F96.00$24.20 per million BTU of heat
Navien NFB700-20096.00$24.20 per million BTU of heat
Navien NFB700-150F96.00$24.20 per million BTU of heat
Navien NFB700-15096.00$24.20 per million BTU of heat
Navien NFB700-110F96.00$24.20 per million BTU of heat
Navien NFB700-11096.00$24.20 per million BTU of heat
Navien NCB700-250/15096.00$24.20 per million BTU of heat
Navien NCB700-240/13096.00$24.20 per million BTU of heat
Navien NCB700-240/11096.00$24.20 per million BTU of heat
Navien NCB700-190/08096.00$24.20 per million BTU of heat
Navien NCB700-190/06096.00$24.20 per million BTU of heat
Ruud RUHBH-L99*96.00$24.20 per million BTU of heat
Ruud CRUHBH-L99*96.00$24.20 per million BTU of heat
Richmond RMHBH-L99*96.00$24.20 per million BTU of heat
Rheem RHBH-L99*96.00$24.20 per million BTU of heat
Rheem ECOHBH-L99*96.00$24.20 per million BTU of heat
Rheem CRHBH-L99*96.00$24.20 per million BTU of heat
Rheem CRCBH-L99*96.00$24.20 per million BTU of heat
IBC Technologies SL 10-85G396.00$24.20 per million BTU of heat
IBC Technologies SFC 99*96.00$24.20 per million BTU of heat
IBC Technologies SFB 99*96.00$24.20 per million BTU of heat
Energy Kinetics Accel CS EK1C 12096.00$24.20 per million BTU of heat
Viessmann CU3A-9495.00$24.45 per million BTU of heat
Viessmann CU3A-19995.00$24.45 per million BTU of heat
Viessmann CU3A-16095.00$24.45 per million BTU of heat
Viessmann CU3A-12595.00$24.45 per million BTU of heat
Viessmann B2TB-12595.00$24.45 per million BTU of heat
Viessmann B2HE-8595.00$24.45 per million BTU of heat
Viessmann B2HE-19995.00$24.45 per million BTU of heat
Viessmann B2HE-15095.00$24.45 per million BTU of heat
Viessmann B2HE-12095.00$24.45 per million BTU of heat
Viessmann B1KE-19995.00$24.45 per million BTU of heat

Computed from electricity at 18.34¢/kWh, the EIA average for US in June 2026 and gas at $24.09/Mcf for June 2026. A kilowatt-hour is 3412 BTU. Gas volume is converted to heat at 1.037 million BTU per thousand cubic feet, EIA's published average. This is a rate times a rating, not a prediction of your bill.

By brand

Weil-McLain (38) · Lochinvar (33) · Camus Hydronics Ltd. (32) · Utica Boilers (32) · NTI (30) · U.S. Boiler Company (30) · Navien (28) · Rheem (28) · Burnham by U.S. Boiler (24) · Viessmann (22) · IBC Technologies (21) · New Yorker (21) · Ruud (21) · Peerless (20) · Velocity Boiler Works (19) · Dunkirk (18) · Bosch (16) · HTP (15) · PurePro (15) · Rinnai (14) · Dunkirk Boilers (13) · Bradford White (12) · Energy Kinetics (12) · Laars (12) · Solaia (11) · Conforto (10) · Saint Roch (9) · Radiant (7) · Eco King Supreme (6) · Eco-King (6) · Force (6) · Glow Brand (5) · Pensotti (5) · Richmond (5) · Triangle Tube (5) · Vesta (5) · Vesta. DS, Inc. (5) · Williamson-Thermoflo (5) · Buderus (4) · Raypak (4)

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Source: ENERGY STAR certified product data, published by the U.S. EPA and used with attribution. This is a register of certified models, not of every model on the market. ENERGY STAR is a registered mark of the U.S. EPA; this site is not affiliated with or endorsed by EPA or DOE.