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COMBOU 70-20US

Thermal2000 bth ULTRA 20kw, 68k BTU/hr Combination Electric Boiler/Water Heater, 70 Gal.

A combination without compromise

The ComboMax ULTRA is an electric boiler combined with an instantaneous water heater for residential applications. Available in two sizes, the ComboMax ULTRA offers performance levels from 4.5 kW to 29 kW. This 2-in-1 solution can easily heat large buildings of up to 4750 sq.ft. and provide domestic hot water in less than 7 seconds. Almost maintenance-free, it offers incredible energy efficiency! This unit requires less space, provides quality water, and has a long lifespan. What’s more, the ComboMax ULTRA is covered by a 15-year warranty. Thanks to its T2 UltraSmartTM controller, it offers optimal comfort with accurate temperature management.

Factory Direct
5,375.66 5,375.66

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  • Manufacturer
  • Electrical
  • Max Working Pressure
  • NSF Listed
  • Fuel Type
  • Heat Output (BTU/hr)
  • Stages
  • Electrical Supply (Awg)
  • DHW Production in 1 hr (Gal)
  • DHW Production in 10 min (Gal)
  • Mounting
  • Condensing
  • Output Capacity (BTU/hr)
  • DHW Capability
  • Heat Exchanger Material
  • Water Connection Size
  • Warranty (Heat Exchanger)
  • Warranty (Parts)
  • Input Capacity (BTU/hr)
  • Vent Type
  • Amp Draw
  • Voltage
  • Power (kW)
  • Breaker (Amp)
Terms and Conditions
30-day money-back guarantee
Shipping: 2-3 Business Days
Manufacturer: Thermo2000
Electrical: 120/240 VAC, 60 Hz, 1-phase
Max Working Pressure: 30 psi
NSF Listed: Yes
Fuel Type: Electric
Heat Output (BTU/hr): 68922
Stages: 4
Electrical Supply (Awg): 3 Cu, 2 Al
DHW Production in 1 hr (Gal): 186
DHW Production in 10 min (Gal): 89
Mounting: Floor-Standing
Condensing: No
Output Capacity (BTU/hr): 68,200 BTU/hr
DHW Capability: Combi
Heat Exchanger Material: Copper
Water Connection Size: 1-1/4 in. NPT
Warranty (Heat Exchanger): 15 years (residential), 10 years (commercial)
Warranty (Parts): 2 years
Input Capacity (BTU/hr): 68,200 BTU/hr
Vent Type: N/A
Amp Draw: 83
Voltage: 240 VAC / 60 Hz / 1 Phase
Breaker (Amp): 110
Voltage (VAC/Hz/Phase)240 VAC / 60 Hz / 1 Phase
Power (kW)20
Heat Output (BTU/hr)68922
Current Load (Amps)83
Elements (kw)4 x 4 kW
Stages4
Electrical Supply (Awg)3 Cu, 2 Al
Breaker (Amp)110
DHW Production in 10 min (Gal)89
DHW Production in 1 hr (Gal)186