Williamson Oil Boiler Products We Carry

Efficiencies 86% - 87% AFUE
Enhanced control
- Temperature limit control
- LWCO Function
- Thermal pre-purge function
Rear flue outlet
- Top flue available with optional kit
Easy service
- Swing-away burner door
- Top access cleanout cover
- Plug-in wiring harness
High efficiency oil burner
- Solenoid valve
- PSC motor
- Solid state ignitor
Cast iron sections with built-in air separator
Insulated heavy-gauge steel jacket

Boiler Model	Burner Input		AHRI Certified Ratings			Minimum Chimney Size (x 15' High)
	Burner Input		Heating Capacity MBH	Net Rating (water) MBH	Seasonal Efficiency AFUE%
	GPH	MBH
	GPH	MBH				Rectangle	Round
OWB-3	0.70	98	86	75	86.4	8" x 8"	6"
OWB-3*	0.95	133	115	100	86.0	8" x 8"	6"
OWB-4	1.00	140	122	106	86.2	8" x 8"	6"
OWB-4*	1.20	168	146	127	86.0	8" x 8"	6"
OWB-5	1.20	168	147	128	86.1	8" x 8"	7"
OWB-5*	1.45	203	176	153	86.0	8" x 8"	7"
OWB-6	1.40	196	171	149	86.1	8" x 8"	7"
OWB-6*	1.75	245	213	185	86.0	8" x 8"	7"
* The specific higher input rates are compliant when installed with required High Input Damper kit, Part #381-800-515WT (sold separately) Williamson has determined the boilers listed below are compliant with ENERGY STAR^® Program 3.0 when installed with (optional) OVD kit.
OWB-3-T-S3-D	0.70	98	86	75	87	8" x 8"	6"
OWB-4-T-S3-D	1.00	140	123	107	87	8" x 8"	6"
OWB-5-T-S3-D	1.20	168	148	129	87	8" x 8"	7"
OWB-6-T-S3-D	1.40	196	173	150	87	8" x 8"	7"

Williamson Oil Boilers