Share this page
Effortless comfort, Maximum Efficiency
WGO Series 4 Oil-Fired Water Boiler
Features
Optimized System
Dedicated water-only oil boiler with cast iron sections – no tankless heater or cover plate
Easy Access
Quick open top and swing-away burner door with full chamber access increases visibility for inspection and servicing
Venting Options
Two flue outlets- rear and top – for complete venting flexibility
thoughtful Design
Recessed target wall design protects unit from flue brushes
Reliability
Includes factory-wired circulator (when specified), service switch and Weil-McLain exclusive captured elastomer seals for added reliability
Flexible Install
Available assembled or as a knockdown for installation areas with limited space
big on warmth, low on energy use
Engineered for comfort, designed for efficiency
Certified ENERGY STAR® and heat pump ready, this high-efficiency boiler delivers powerful, eco-friendly performance while keeping energy costs low.
Technical Specs
| MODEL | BURNER INPUT RATING GPH | BURNER INPUT RATING MBH | HEATING CAPACITY (MBH) | NET RATINGS (MBH) | AFUE | DRAFT LOSS THROUGH BOILER (IN. W/C) | MIN. CHIMNEY SIZE RECTANGULAR (IN.) | MIN. CHIMNEY SIZE ROUND (IN.) | MIN. CHIMNEY SIZE HEIGHT (FT.) | APPROX. SHIPPING WEIGHT (LBS.) | ENERGY STAR® |
|---|---|---|---|---|---|---|---|---|---|---|---|
| WGO-2 | 0.7 | 98 | 86 | 75 | 86.4 | 0.1 | 8×8 | 6 | 15 | 540 | |
| WGO-2RD | 0.7 | 98 | 86 | 75 | 87 | 0.01 | 8×8 | 6 | 15 | 540 | YES |
| WGO-3R | 0.8 | 112 | 98 | 85 | 86.2 | 0.02 | 8×8 | 6 | 15 | 595 | |
| WGO-3RD | 0.8 | 112 | 98 | 85 | 87 | 0.01 | 8×8 | 6 | 15 | 595 | YES |
| WGO-3D | 0.95 | 133 | 115 | 100 | 86 | 0.02 | 8×8 | 6 | 15 | 595 | |
| WGO-4R | 1 | 140 | 122 | 106 | 86.2 | 0.01 | 8×8 | 6 | 15 | 645 | |
| WGO-4RD | 1 | 140 | 123 | 107 | 87 | 0.01 | 8×8 | 6 | 15 | 645 | YES |
| WGO-4D | 1.2 | 168 | 146 | 127 | 86 | 0.01 | 8×8 | 6 | 15 | 645 | |
| WGO-5R | 1.2 | 168 | 147 | 128 | 86.1 | 0.015 | 8×8 | 7 | 15 | 760 | |
| WGO-5RD | 1.2 | 168 | 148 | 129 | 87 | 0.015 | 8×8 | 7 | 15 | 760 | YES |
| WGO-5D | 1.45 | 203 | 176 | 153 | 86 | 0.015 | 8×8 | 7 | 15 | 760 | |
| WGO-6R | 1.4 | 196 | 171 | 149 | 86.1 | 0.015 | 8×8 | 7 | 15 | 860 | |
| WGO-6RD | 1.4 | 196 | 173 | 150 | 87 | 0.015 | 8×8 | 7 | 15 | 860 | YES |
| WGO-6D | 1.75 | 245 | 213 | 185 | 86 | 0.015 | 8×8 | 7 | 15 | 860 | |
| WGO-7R | 1.6 | 224 | 196 | 170 | 86 | 0.015 | 8×8 | 8 | 15 | 930 | |
| WGO-7RD | 1.6 | 224 | 197 | 171 | 87 | 0.015 | 8×8 | 8 | 15 | 930 | YES |
| WGO-7D | 2 | 280 | 244 | 212 | 86 | 0.015 | 8×8 | 8 | 15 | 930 | |
| WGO-8 | 2.3 | 322 | 266 | 231 | – | 0.025 | 8×12 | 8 | 20 | 1,030 | |
| WGO-9 | 2.55 | 357 | 295 | 257 | – | 0.03 | 8×12 | 8 | 20 | 1,135 |
More Residential Boilers
-
Simplicity Gas Combi Boiler
-
ECO Tec
-
Evergreen Pro Gas Boiler
-
CGi Gas Boiler Series 4
-
AquaBalance Series 2
-
Ultra S4 Gas Boiler
-
GV90+ Gas Boiler
-
EG Series 6 Gas Boiler
-
WTGO Series 4 Oil-Fired Water Boiler
-
SGO Series 4 Oil-Fired Steam Boiler
-
Ultra Oil Boiler
-
CGa Gas Boiler Series 3
