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Effortless comfort, Maximum Efficiency
WTGO Series 4 Oil-Fired Water Boiler
Features
Optimized System
Oil-fired water boiler with cast iron sections
Tankless Heater
High capacity / high efficiency tankless heater
Easy Access
Quick open top and swing-away burner door with full chamber access increases visibility for inspection and servicing
Reliability
Includes factory-wired circulator (when specified), service switch and Weil-McLain exclusive captured elastomer seals for added reliability
thoughtful Design
Recessed target wall design protects unit from flue brushes
Venting Options
Two flue outlets- rear and top – for complete venting flexibility
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 | TANKLESS HEATERINTERMITTENT DRAW RATING (GPM) | DRAFT LOSS THROUGH BOILER (IN. W/C) | RECTANGULAR (IN.) | ROUND (IN.) | HEIGHT (FT.) | APPROX. SHIPPING WEIGHT (LBS.). | ENERGY STAR® |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| WTGO-3LR | 0.7 | 98 | 86 | 75 | 86.4 | 3.25 | 0.1 | 8×8 | 6 | 15 | 560 | |
| WTGO-3LD | 0.95 | 133 | 115 | 100 | 86 | 3.25 | 0.01 | 8×8 | 6 | 15 | 560 | |
| WTGO-3R | 0.8 | 112 | 98 | 85 | 86.2 | 3.25 | 0.02 | 8×8 | 6 | 15 | 610 | |
| WTGO-3RD | 0.8 | 112 | 98 | 85 | 87 | 3.25 | 0.01 | 8×8 | 6 | 15 | 610 | YES |
| WTGO-3D | 0.95 | 133 | 115 | 100 | 86 | 3.25 | 0.02 | 8×8 | 6 | 15 | 610 | |
| WTGO-4R | 1 | 140 | 122 | 106 | 86.2 | 3.75 | 0.01 | 8×8 | 6 | 15 | 660 | |
| WTGO-4RD | 1 | 140 | 123 | 107 | 87 | 3.75 | 0.01 | 8×8 | 6 | 15 | 660 | YES |
| WTGO-4D | 1.2 | 168 | 146 | 127 | 86 | 3.75 | 0.01 | 8×8 | 6 | 15 | 660 | |
| WTGO-5R | 1.2 | 168 | 147 | 128 | 86.1 | 4 | 0.015 | 8×8 | 7 | 15 | 775 | |
| WTGO-5RD | 1.2 | 168 | 148 | 129 | 87 | 4 | 0.015 | 8×8 | 7 | 15 | 775 | YES |
| WTGO-5D | 1.45 | 203 | 176 | 153 | 86 | 4 | 0.015 | 8×8 | 7 | 15 | 775 | |
| WTGO-6R | 1.4 | 196 | 171 | 149 | 86.1 | 4.25 | 0.015 | 8×8 | 7 | 15 | 875 | |
| WTGO-6RD | 1.4 | 196 | 173 | 150 | 87 | 4.25 | 0.015 | 8×8 | 7 | 15 | 875 | YES |
| WTGO-6D | 1.75 | 245 | 213 | 185 | 86 | 4.25 | 0.015 | 8×8 | 7 | 15 | 875 | |
| WTGO-7R | 1.6 | 224 | 196 | 170 | 86 | 5.5 | 0.015 | 8×8 | 8 | 15 | 930 | |
| WTGO-7RD | 1.6 | 224 | 197 | 171 | 87 | 5.5 | 0.015 | 8×8 | 8 | 15 | 930 | YES |
| WTGO-7D | 2 | 280 | 244 | 212 | 86 | 5.5 | 0.015 | 8×8 | 8 | 15 | 930 | |
| WTGO-8 | 2.3 | 322 | 266 | 231 | – | 5.75 | 0.025 | 8×12 | 8 | 20 | 1,030 | |
| WTGO-9 | 2.55 | 357 | 295 | 257 | – | 6 | 0.03 | 8×12 | 8 | 20 | 1,135 |
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