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Bosch Therm 660 EFO NG (Natural Gas) - Outdoor

Product Overview

Bosch Therm 660EFO-NG (Natural Gas) whole-house outdoor tankless water heater

140,000 BTUs and up to 160 degrees F, Electronic Ignition, Energy Star, 2013 Federal Tax Credit Eligible

In stock


Eligible for Free Ground Shipping on orders over $199

Our Price:

Regular Price: $1,060.00

Special Price: $599.00


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Bosch Therm 660 EFO NG (Natural Gas) Outdoor Whole-House Tankless Water Heater

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  • Bosch Therm 660 EFO NG (Natural Gas) Outdoor Whole-House Tankless Water Heater
Save 10% (up to $300) with the 2011 Federal Tax Credit for qualified Gas Tankless Water Heaters.
  • Bosch Therm 660EFO Outdoor Tankless Water Heater

    The Therm 660 EFO is compact and is designed to be installed outdoors in approved non-freezing areas. But don't let the size fool you. This model is loaded with features including freeze protection and built-in high temperature capability (160 degrees F).

    At 140,000 BTUs/hr maximum input, this tankless water heater can supply a shower and a sink simultaneously. It features an electronic ignition system.

    This heater is Energy Star rated and qualifies for the 2013 federal tax credit.
  • Brand Bosch Therm
    Model Bosch Therm 660 EFO-NG
    Gas Type Natural Gas
    Product Type Whole House
    Indoor/Outdoor Installation Outdoor
    Heater Style Tankless
    Application Commercial,Residential
    Product Dimensions (H" x W" x D") 20.5 x 13.8 x 6.7
    Product Weight (Lbs) 36
    Shipping Weight (Lbs) 44.0000
    Capacity @ 35 Deg F Temp Rise (GPM) 6.6
    Capacity @ 45 Deg F Temp Rise (GPM) 5
    Capacity @ 55 Deg F Temp Rise (GPM) 4.2
    BTU Rating 140000
    Maximum Input (BTUs) 140000
    Minimum Input (BTUs) 20000
    Maximum Output (BTUs) 114800
    Minimum Output (BTUs) 16400
    Altitude Test (Ft) 4500
    Temperature Range (Deg F) 100 - 160
    Venting Options N/A
    Venting Diameter (Inches) N/A
    Vent Maximum Run (Ft) N/A
    Water Connections (Inches) 3/4 NPT
    Activation Flow Rate (GPM) 0.5
    Water Pressure Rating (PSI) 30 - 150
    Energy Factor 0.82
    Remote Control Optional Wired Remote Available
    Warranty 15-year limited warranty on the heat exchanger (3-year if used in recirculating applications); 5-year limited warranty on all other parts
  • Customer Reviews

    EXCELLENT SERVICE!!! Review by Gerry
    I have experience with Bosch GWH and love them; the unique part of buying them from ProWaterHeaterSupply is the amazing service you get; these guys are genuinely interested in helping you get everything out of the experience of buying and installing quality products. Thanks you guys! (Posted on 12/15/12)

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  • Warranty

    Bosch gas tankless water heaters, electric tankless water heaters, electric mini-tank water heaters and accessories are warranted directly by the Manufacturer (BOSCH) through Bosch Thermotechnology Corp.

    Please visit the web site Warranty Page for the full details of the Bosch product warranty.

    Be sure to fill out your Warranty Card and send it to Bosch immediately after your installation to ensure you are registered for the full product warranty.
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