The GE RealMAX Choice 40-gallon tall power vent water heater is a good choice when a standard chimney-style vent is not practical. A built-in blower pushes exhaust out through plastic vent pipe, so it can run sideways out a wall or straight up through the roof.

The tank holds a true 40 gallons, and the 42,000 BTU natural gas burner delivers up to 82 gallons of hot water in the first hour, enough for a household of up to four people. It vents with 2- or 3-inch PVC, CPVC, ABS or polypropylene pipe, with runs of up to 150 feet using 3-inch pipe (maximum length depends on pipe size and altitude). The blower plugs into a standard 120-volt outlet.

GE's SmartShield safety system shuts the unit off if it senses abnormal temperatures or flammable vapors, and an LED light reports the status of the gas system. A full-port brass drain valve and a magnesium anode rod help it last, and it is backed by an 8-year limited tank and parts warranty.

Key features:

• 40-gallon true capacity, natural gas

• 42,000 BTU burner

• First-hour rating: 82 gallons

• Uniform Energy Factor (UEF): 0.68

• Power vent, horizontal or vertical: 2" or 3" PVC, CPVC, ABS or PP pipe, up to 150 ft with 3" pipe (varies by altitude)

• Plugs into a standard 120V outlet (8.5 ft cord included)

• SmartShield safety system and self-diagnostic LED status light

• Full-port brass drain valve; magnesium anode rod; 3/4" water and 1/2" gas connections

• About 66-1/3" tall x 20" diameter

• 8-year limited tank and parts warranty; 1-year limited labor

Built in Camden, South Carolina, with 70-90% U.S. content, according to GE.