Gas Tankless Water Heaters

Therm 660 EF

^{Energy Efficient}

Space saving design with non-condensing technology
Therm 660 EF

Product Overview

Eligible for up to $1500 Federal Tax Credit (30% of purchase price and residential installation)

The Therm 660 EF is compact enough to install virtually anywhere. But don’t let the size fool you. This model is loaded with features including freeze protection and built-in high temperature capability (160°F).

Features & Benefits

Super compact 14" x 20½" x 7" size
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
Electronic ignition
Built in freeze protection
Vents vertically or horizontally with 3” or 4” stainless steel
Can be used in recirculation and space heating applications
Backed with 15-year warranty
Available in NG and LP models
Also available as an outdoor model, 660 EFO

Warranty

15 year limited warranty on heat exchanger; 3 year warranty if used in direct recirculating applications

15 year warranty on heat exchanger if used if recirculated through a storage tank such as the Ariston mini-tank

5 year warranty on all other parts

Bosch Warranty Details

Product Warranty

Therm 660 EF	Specifications
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	0.5 gpm
Temp Range (°F)	100 - 160
Temp Stability (°F)	+/- 2
Default Temp (°F)	120
Energy Factor	.82
Thermal Efficiency	83%+
Installation Options	Indoor
Dimensions (w x h x d)	14" x 20½" x 7"
Weight (lbs.)	36
Inlet Connection	¾" NPT
Outlet Connection	¾" NPT
Gas Connection	¾" NPT
Max Water Pressure	150 psi
Min Water Pressure	30 psi
Min NG Presure	4" WC
Condensing Heat Exchanger	n/a
Venting Options	Stainless Steel
Vent Maximun Run	35'
Energy Star Rated	Yes