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Intellihot iQ251D Gen II - i Series - Tankless Water Heating Systems

Special Price $15,312.00 Regular Price $19,140.00
In stock
iQ251D Gen II
Intellihot iQ251D Gen II - i Series - Tankless Water Heating Systems

Intellihot iQ251D Gen II - i Series - Tankless Water Heating Systems   

Smarter, versatile, deionized water heating for labs, factories, and plants. Industrial environments demand rugged, deionized-water heaters—and this model meets the challenge. Built for tight spaces and tough conditions, the iQ251D is the most compact and only gas-fired deionized tankless water heater on the market. 

With 96% thermal efficiency and flexible design and circuit options, iQ251 and iQ251D models are the best-in-class wall-hung, ASME-compliant, tankless water heaters. These wall-hung iQ models are constructed for maximum durability and the most demanding commercial and industrial applications. The iQ251D is the only gas-fired, deionized on-demand water heater on the market. Both iQ251 and iQ251D deliver 251,000 BTU/hr


  • Wi-Fi & Cellular Connectivity - Real-time monitoring of your Gen II unit is available through the unit's 3.5" touch-screen - and accessible remotely via a mobile app. Each unit can be easily connected to your building's Wi-Fi router or Intellihot's internet hub. 

  • Masterless Cascading- Eliminate single-point failure with our patented Masterless Cascading technology. If one cascaded unit is offline for servicing, all other units regroup and continue to operate. Cascade up to 2,510,000 BTu/hour (10 units) for larger applications. 

  • Eliminate Mixing Valves & Lower Legionella Risks- With no storage tanks, there's a lower risk for Legionella growth. By eliminating the need for mixing valves, these features also reduce their associated unreliability and costs. 

  • Full Modulation - Smart units deliver maximum BTU/hr input when needed and zero BTU/hr the rest of the time

  • Gas-Fired - By using natural gas our system lower operating costs and improve ROI vs. electric water heaters. 73KW of heating capacity available with low-pressure drop; capable of 9.6 GPM at 50F temperature rise.

  • Common Venting Capabilities - The iQ251 and iQ251D units transform common venting into smart-common venting. 

  • ASME-HLW Compliant - Suitable for applications managed by engineers, specifiers, and contractors. 


  • Minimum Input (BTU/hr) - 30,000

  • Maximum Input (BTU/hr) - 251,000

  • Maximum Output (BTU/hr) - 240,960

  • Thermal Efficiency - 96%

  • Dimensions H x W x D (inches) - 26.2 x 17.7 x 15

  • Weight (LBS) - 93 LBS 

  • Water Pressure Min/Max (PSI) - 30/160

  • Vent Size (Diameter) - 3"

  • NG/LP- (Maximum Static Gas Pressure Range) - 2.5" - 14" WC

  • Electrical (120V AC, 60Hz) - 120V AC, 60Hz

More Information
SKU iQ251D Gen II
MPN iQ251D Gen II
Weight 125.000000
Manufacturer Intellihot
UPC 850007779672
Generic Product Category Tankless Water Heater
Voltage 120V

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