PRODUCT DESCRIPTION

Bosch ProTankless™ GWH 425 HNO-L (PROPANE)

Install your tankless water heater outside!

The Bosch ProTankless™ GWH 425 HNO incorporates the same revolutionary hydro-generated ignition system as the GWH 425 HN, allowing the water heater to operate without a standing pilot, electricity, or a battery. However, the Bosch ProTankless ™ GWH 425 HNO is designed to be installed outside and has built-in freeze protection to 5°F.

• Installs outside – built-in freeze protection to 5°F.
• Energy factor: .80 NG / .84 LP
• Thermal efficiency: 80% NG / 83% LP

TECHNICAL SPECIFICATIONS Power Input NG: 28,000 - 117,000 Btu LP: 28,000 - 117,000 Btu Minimum Flow Rate to Activate 0.5 gallons per minute (gpm) Flow Rates 90° F rise / 2.1 gpm 75° F rise / 2.4 gpm 65° F rise / 2.9 gpm 55° F rise / 3.4 gpm 45° F rise / 4.2 gpm Energy Factor NG: .85 LP: .84 Thermal Efficiency NG: 80% LP: 83% Dimensions 29¾"h x 18¼'w x 8¾”d Weight 57 lbs. Ignition Hydro-generated Accessories Power Vent Kit - AQ1 Modulating Gas Valve Yes Life Expectancy 20+ years INSTALLATION SPECIFICATIONS Gas Connection 3/4" Female NPT Water Connection ½" Male NPT NG Gas Pressure Minimum: 7" WC Maximum: 14 " WC Minimum: 11" WC Maximum: 14" WC Water Pressure Minimum: 30 PSI Maximum: 150 PSI Electrical Supply None

HIGH ALTITUDE OPERATION

Altitude Natural Gas Liquid Propane Special Notes  0 - 4,000 ft (0-1,219 m) no modification no modification For operation at elevations above 2,000 ft (610 m) the equipment ratings shall be reduced at the rate of 4% for each 1,000 ft (305 m) above sea level. 4,000 ft - 7,000 ft (1,219m-2,134m) CO2 adjustment with flue gas analyzer required Refer to this tech bulletin. Above 7,000 ft (above 2,134 m) Not approved