Condensing Boiler

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E50C click to zoom into photo of
  • Most efficient combi boiler on the market—95.6% AFUE
  • Cost-effective, simplified installation—fewer components needed
  • No primary secondary piping or closely spaced tees required*
  • No system pumps required—reduces install time and cost
  • Fewer maintenance intervals required than the competition— Inspection every two years or 4,000 hours; Service every four years or 8,000 hours
  • 13,600 to 50,000 BTU heating load
  • Proprietary stainless steel heat exchanger for unmatched performance and durability
  • Greater control—system temperature adjustable in two-degree increments
  • Automatic de-aeration at start-up

Width: 19.7 inches (500 mm)

Height: 25.6 inches (650 mm)

Depth: 15.6 inches (395 mm)


91 lbs (41.3 kg)

Gas Type

Natural Gas, Propane with conversion kit

Maximum Heating Capacity

47,000 BTU (13.8 kW)

Minimum Input

13,000 BTU (3.8 kW)

Maximum Input

85,000 BTU (25 kW)

Maximum Input (Heating)

50,000 BTU (15 kW)

Turn Down Ratio


DHW Activation Rate

0.39 Gallon/Minute (1.84 Liter/Minute)

Maximum DHW at 75°F ΔT

2.1 Gallon/Minute

Maximum DHW at 41.7°C ΔT

7.9 Liter/Minute



Circulating Pump

​Single Speed

Storage Capacity


Approved Venting Material

​Polypropylene, Stainless Steel, PVC, CPVC


​Standard Warranty (some restrictions apply):

Residential: 12-year on heat exchanger, 2-year on parts, 1-year on labor

Commercial: 5-year on heat exchanger, 2-year on parts, 1-year on labor



Included in the Box

• Wall mounting bracket

• Outdoor reset sensor

• Flow restrictor

• 3” (80 mm) twin pipe adapters for venting (PVC and PP)

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