Share this page
Effortless comfort, Maximum Efficiency
88 Series 2 Commercial Gas Oil Boiler

The Weil-McLain 88 Series 2 is a high-efficiency commercial boiler designed for reliable steam heating in schools, hospitals, and industrial buildings. With thermal efficiencies up to 85.6%, it supports multiple firing modes and fuel types, and its durable cast iron design ensures long-lasting performance and easy maintenance.
Features
High Efficiency
85.6% thermal efficiency
Flexible Firing
On/Off, Low/High/Off, Low/High/Low, or Full Modulation
Heater Options
With or without tankless heater
Install Choices
Packaged or knock-down
Fuel Flexibility
Gas, Oil or Gas/Oil
LEED Compliant
Complies to LEED
Boiler Type
Steam Boiler
Wide Range
1010 – 5845 MBH input
Horsepower Range
24-145 H.P.
Flexible Configuration
Single or multiple boiler systems
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 | INPUT LIGHT OIL (MBH) | INPUT GAS (MBH) | GROSS OUTPUT (MBH) | NET STEAM (SQ. FT.) | OIL THERMAL EFFICIENCY (%) | GAS THERMAL EFFICIENCY (%) | FLUE OUTLET DIAMETER (IN.) | BOILER STEAM CONTENT (GALLONS) | APPROX. SHIPPING WEIGHT (LBS.) |
---|---|---|---|---|---|---|---|---|---|
1088 | 2,990 | 3,082 | 2,561 | 8,383 | 85.6 | 83.1 | 14 | 247 | 6,130 |
1188 | 3,325 | 3,428 | 2,848 | 9,213 | 85.7 | 83.1 | 14 | 270 | 6,695 |
1288 | 3,660 | 3,773 | 3,135 | 10,147 | 85.7 | 83.1 | 14 | 293 | 7,260 |
1388 | 3,995 | 4,119 | 3,422 | 11,071 | 85.7 | 83.1 | 14 | 316 | 7,890 |
1488 | 4,330 | 4,464 | 3,709 | 12,000 | 85.7 | 83.1 | 16 | 339 | 8,410 |
1588 | 4,665 | 4,809 | 3,996 | 12,925 | 85.7 | 83.1 | 16 | 362 | 9,005 |
1688 | 5,000 | 5,155 | 4,283 | 13,854 | 85.7 | 83.1 | 16 | 385 | 9,525 |
1788 | 5,335 | 5,494 | 4,570 | 14,783 | 85.7 | 83.1 | 18 | 408 | 9,780 |
1888 | 5,670 | 5,845 | 4,857 | 15,713 | 85.7 | 83.1 | 18 | 431 | 10,775 |
488 | 980 | 1,010 | 839 | 2,621 | 85.6 | 83.1 | 10 | 109 | 2,860 |
588 | 1,315 | 1,356 | 1,126 | 3,521 | 85.6 | 83.1 | 10 | 132 | 3,340 |
688 | 1,650 | 1,701 | 1,413 | 4,469 | 85.6 | 83.1 | 10 | 155 | 3,820 |
788 | 1,985 | 2,046 | 1,700 | 5,463 | 85.6 | 83.1 | 12 | 178 | 4,345 |
888 | 2,320 | 2,382 | 1,987 | 6,427 | 85.6 | 83.1 | 12 | 201 | 4,925 |
988 | 2,655 | 2,737 | 2,274 | 7,358 | 85.6 | 83.1 | 14 | 224 | 5,600 |
Downloads