Specifications
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Definitions
American Naonal Standards Instute (ANSI) - Agency
that set standards for safety of gas water heaters.
Anode - Material that current ows from inside a baery.
Anode Rod - Sacricial part made of aluminum,
magnesium or other compounds that is corroded by
electrical currents in order to protect the inside of the
tank.
Back Dra - The back ow of air into the ue. Usually
caused by negave air pressure in the home or improper
vent terminaon.
BTU - (Brish Thermal Unit) The amount of energy
required to heat one pound of water by 1°F.
Carbon Monoxide - Poisonous gas that is a by-product of
incomplete combuson. Carbon monoxide is harmful or
fatal to breathe and has to be vented to the outdoors.
Excessive carbon monoxide is an indicaon of poor
combuson. The cause must be invesgated and
immediately eliminated.
Cathode - Material that current ows to inside a baery.
Cathodic Protecon - Protecon supplied by a
sacricial anode to prevent corrosion of other parts.
Check Valve - A one-way valve installed to prevent reverse
ow of water in a piping system.
Closed Water System - A water system where a check
valve prevents the ow of expanding water back into the
municipal water supply and includes no provision for
thermal expansion.
Cold Water Inlet Temperature - The temperature of the
water coming from the water supply to the water heater.
Combuson Chamber - Part of the gas water heater,
located in the jacket base assembly, where the burner is
located and combuson takes place.
Condensaon - Water droplets formed as the temperature
drops below the dew point. The amount of condensaon
is aected by the amount of humidity in the air. A
common example is water droplets that form inside the
ue and on the boom tank head when very cold water is
introduced into a gas water heater. Condensaon may
cause a sizzling sound to be heard as the water droplets
fall onto the burner below.
Control Circuit - Parts that measure tank temperature,
direct the unit to begin heang and provide safety controls
to prevent overheang or other unsafe operang
condions.
Dielectric Connecons - Water connectors that stop the
ow of electricity from the house piping to the water
heater.
Dip Tube - Tube that moves incoming cold water to the
boom of the tank to prevent it from mixing with stored
hot water at the top of the tank.
DOE - (Department of Energy) Government agency that
regulates water heater eciencies.
Drain Valve - Child-resistant valve located near the boom
of the water heater to provide a way to drain the water
heater for maintenance purposes.
Dry Firing - Energizing a heang element before it is
completely covered in water. Dry ring will cause the
standard heang element to burn out immediately.
Energy Cuto Switch - (ECO) Gas water heater safety
device that shuts o gas supply to the unit if water
temperature exceeds 180°F. The ECO is a single-use switch
and requires complete replacement of the enre
thermostat if acvated.
Energy Factor - Overall eciency of a water heater
calculated by tesng tank draw eciency, recovery
eciency and standby eciency using the DOE protocol.