Specifications

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Definitions
Pilot Light - A small ame that stays lit all the me and
ignites the burner ame.
Potable Water - Water that is suitable for drinking
because it contains nothing harmful.
Radiant Hydronic Heang - Home heang system that
circulates hot water through tubes in the oor or through
baseboard heaters.
Recovery Capacity - The number of gallons of
incoming cold water per hour the water heater can heat to
a specic temperature.
Recovery Eciency - (Thermal Eciency) A measure of
the total amount of heat produced by the water heater
that is transferred to the water.
Scale - Salts formed and deposited inside the water
heater or on xtures. Somemes referred to as lime
deposits.
Smelly Water – Usually ground water that contains
hydrogen sulde gas. The smell is caused by
sulfate-reducing bacteria that thrive under condions
found inside a water heater.
Stacking - Very high temperatures at the top of the tank
caused by increased cycling of the burner or heang
elements during short draws of water.
Standby Eciency - A measure of how much heat is lost
from the stored water while the water heater is not
heang water.
Surface Water - Water that comes from lakes, streams and
reservoirs.
Suspended Solids - Small parcles of sand, dirt, silt, clay,
algae or decaying vegetaon that are suspended in water.
T&P Valve - (Temperature and Pressure Relief Valve)
Safety device that releases hot water when
temperatures inside the tank reach 210°F, or when
pressure exceeds 150psi.
Tank - Part of the water heater that holds the stored hot
water. Constructed of welded steel and glass lined to
prevent corrosion.
Tank Draw Eciency - A measure of the amount of usable
hot water that can be drawn from the tank.
Temperature Rise - The dierence between the incoming
cold water temperature and the hot water produced.
Thermal Expansion - Expansion of water as it is heated.
Thermistor - Electronic device used in place of a
mechanical thermostat that measures water
temperature.
Thermocouple - Safety device that generates a small
electrical current used to energize a safety magnet inside
the gas valve.
Thermostat - Device that measures water temperature.
Usable Hot Water - Water that is less than 20°F below the
thermostat seng.
Wa - Measure of electric power. 1,000 Was = 1 Kilowa
Working Pressure - The maximum daily pressure the
water heater is rated for, usually 150psi.