Product Overview

Rinnai Tankless Water Heater Operation
Water Heater Technology
Fuel Type/
Energy Source
EF
(Energy Factor)
Annual Operating Costs
Standard 50-Gallon Gas Storage Tank Natural Gas 0.60 $273
Standard 50-Gallon Gas Storage Tank Propane 0.60 $646
Standard 50-Gallon Electric Storage Tank Electricity 0.95 $557
Mid-Efficiency Non-Condensing Tankless Natural Gas 0.82 $200
Mid-Efficiency Non-Condensing Tankless Propane 0.82 $473
High Efficiency Condensing Tankless Natural Gas 0.96 $171
High Efficiency Condensing Tankless Propane 0.96 $404
Tank vs. Tankless Annual Operating Costs*
How a Rinnai Tankless Water Heater Works
When the need for hot water arises by turning on a shower, washing
machine, dish washer or faucet, cold water enters the Rinnai
Tankless Water Heater from the inlet pipe at the bottom of the unit.
The PC board is then signaled to activate the ame igniter or ignition.
A combustion fan turns on to allow oxygen into the burner to ignite
the ame as the gas control valve opens at a low frequency. Once
an adequate ame is present the igniter stops from sparking —
beginning the next sequence of operation in a matter of seconds.
Water is heated as it passes through the coils of the copper heat
exchanger, and exits from the hot water outlet pipe to travel through
the pipes of the home or business to the water xture where hot
water is needed.
The gas valve and blower automatically adjusts the incoming gas
and oxygen to meet the water heating demands. If the demand is
small, the Rinnai Tankless Water Heater can use a smaller ame and
less gas. If the demand is greater, the ame can expand across the
width of the entire burner to heat more water. The tankless water
heater adjusts as needed to ensure the temperature set point is
maintained. A digital controller allows the user to choose his desired
temperature.
As the hot water xture shuts o, cold water stops entering the
tankless water heater and the ame diminishes. The combustion fan
continues to operate at a low speed for a short period of time. This
allows the exhaust of any leftover combustion gases.
The tankless burner is on only when hot water is needed
14
*Based on national averages per Department of Energy, U.S. Energy Information Administration.
HOT WATER
OUTLET
COLD WATER
INLET
GAS
INLET
NON CONDENSING
HOT
WATER
OUTLET
COLD
WATER
INLET
GAS
INLET