John Wood Direct Vent Water Heaters

John Wood direct vent water heaters are designed for homes that do not utilize the chimney and where the external power supply cannot be provided for the heater.

Thanks to the sidewall installation and sealed combustion chamber, fresh air is taken from the outside and used for creating an ideal mixture with the natural or propane gas, for clean burning. Thanks to the sealed combustion, there is no need for a flammable vapor sensor.

Due to the airtight design, back-drafting and carbon monoxide leaking are minimized, which makes these units perfect for use even in-room closets. Since there is no electric fan to blow, direct vent water heaters are very quiet. This type of water heater is recommended for homes with space issues and if there is a frequent power outage.

Features review

  • With the direct venting, no external electricity or chimney is required, and the water heater gets the combustion air from the outside atmosphere while removing the products of combustion outdoors at the same time. The venting system is the horizontal and co-axial type (pipe within the pipe).
  • The thermopile design allows proper work of the pilot light even in a harsh environment.
  • The gas control valve incorporates the LED operation status indicator and diagnostic system for easy troubleshooting.
  • Water heaters with a side connection for combined potable water and space heating are available.
  • Flame Safe technology protects the user from the accidental ignition of the flammable vapor from paint, solvents, and some chemicals.
  • Natural gas and propane gas models are available. There are only two models available with 40 and 50-gallon tank capacity.
  • With the absence of the electric blower, the operation is quiet.
  • A heavy-duty anode rod is used for protection against corrosion.
  • The water temperature can be adjusted to the gas control valve and thermostat assembly in the range from 91 F to 155 F. The energy factor is an average but lower than Energy Star models; it is 0.61-0.63.
  • There are two operating modes: standard mode when the temperature controller maintains the set temperature and low setting mode when the temperature is approximately 91 F.
  • Warranty - 8 years.


First Hour Rate 
Energy Factor 
Vent length 
JW640BFNA-FV 40 38,000 73 0.60 34 90 167
JW650TBFNA-FV 50 42,000 87 0.58 38 90 185
JW650THBFNA-FV 60 40,000 88 0.59 49 90 187
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