Bosch Therm 660 EFO LP Tankless Water Heater, Liquid Propane 140,000 BTU Max Non-Condensing - Outdoor, 6.6 GPM

Brand: Bosch
Model: Therm 660 EFO LP
Condition: New
SKU: 826560
In Stock

Bosch Therm 660 EFO LP Gas Tankless Water Heaters

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About the Bosch 120V, Therm Non-Condensing Tankless Water Heater for 2-3 Bathrooms, Outdoor - Liquid Propane

Bosch’s 125 years of experience and service to the industry has led them to become the industry leader, creating innovations that far surpass standards for quality and efficiency. Bosch’s heat exchange burner technology has allowed their water heaters to withstand the test of time, while maintaining maximum efficiency. With the extended product life, greater quality and constant evolution, Bosch’s products all are a depiction of prestige.The Bosch 660 EFO LP is an outdoor tankless water heater unit that utilizes liquid petroleum (propane) as its primary energy source. Regardless of its compact, space-saving design, the Bosch 660 EFO LP produces 140,000 BTUs per hour. With the tank’s 6.6 gallon per minute capacity at 35°F rise, you can supply a sink and a shower simultaneously without losing heat. You’ll be able to enjoy the fastest heat times for continuously running hot water. The Bosch 660 EFO LP does not compromise power for efficiency. The energy factor of the 660 EFO LP is 0.82 and the thermal efficiency rating is at 83%. With the temperature range of 100°F to 160°F, the unit can be used in both residential and commercial applications.The Bosch 660 EFO LP provides versatility that can be used recirculation, thermal and solar configurations to best fit any of your applications. Also, the unit can be used in altitudes of up to 4,500 ft. Bosch backs all of these great features with the industry leading 15-year warranty and a product life expectancy of over 20 years. Bosch also has made their units 100% serviceable, allowing for your next purchase to last a lifetime ahead.Additional Product Information:

  • Suitable for Outdoor use
  • 83% thermal efficiency
  • 140,000 BTU maximum input
  • 6.6 gallons per minute capacity at 35F degree rise
  • Minimum activation flow rate of 0.5 gallons per minute
  • Patented burner design
  • Exclusive safety controls
  • Can be used in solar thermal, recirculation applications
  • Energy Star Certified
  • Built for durability and serviceability with 15 Year Warranty and 20+ Years Product Life Expectancy
  • Condensing/Non-Condensing: Non-Condensing
  • Application: Residential or Commercial
  • Max Input (BTU): 140,000
  • Min Input (BTU): 20,000
  • Capacity at 35°F Rise (gpm): 6.6
  • Capacity at 55°F Rise (gpm): 4.2
  • Intelligent Cascading: No
  • Min Flow Rate: 0.50 gpm
  • Temp Range (°F): 100 - 140
  • Temp Stability (°F): +/- 2
  • Default Temp (°F): 122
  • Energy Factor: .82
  • Thermal Efficiency: 83%
  • Installation Options: Indoor
  • Dimensions (w x h x d): 14" x 20 1/2" x 7"
  • Weight (lbs.): 67
  • Inlet Connection: 3/4" NPT
  • Outlet Connection: 3/4" NPT
  • Gas Connection: 3/4" NPT
  • Max Water Pressure: 150 psi
  • Min Water Pressure: 30 psi
  • Condensing Heat Exchanger: N/A
  • Venting Options: N/A
  • Vent Maximum Run: N/A
  • Energy Star Rated: Yes
Limited 15 Year Warranty
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Questions & Answers

What is the ignition system on the Bosch Therm 660 EFO LP?Is it acceptable to install the 660 EFO LP in a storage shed adjacent to the living quarters if the shed would provide security and weather protection. Or would this be considered and indoor installation and need a vent? Thanks

by Stephen P. on 10-11-2013

Hi Stephen. To help answer your questions I want to refer you to this link to a PDF file of the manual for the Bosch Therm 660 EFO LP. See pg 17. Also, let me give you the direct service line at Bosch. It's 1-800-283-3787. Don't forget to check your local building codes as well. If you need anything else please don't hesitate to give us a call @1-877-998-WEST (9378). Thank you. KMR

on 10-17-2013
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