Rinnai Infinity 20 External, Operation And Installation Manual

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2.5 GENERAL SCHEME AND OPERATION PRINCIPLES
2.5.1 OPERATION PRINCIPLES
Ignition
Press ON/OFF Button of Remote Controller to turn on unit and the remote controller display and priority LED will light
up. When a hot water tap is opened the water flow Sensor revolves and sends a pulse signal to the printed circuit
board (PCB). When the PCB detects water flow it compares the measured temperature to the temperature setpoint.
If required it begins the ignition process with the combustion fan motor starting first. Once the air proving is made the
main solenoid valve and change-over solenoid valves are opened and the burner is lit by the sparking igniter.
Temperature control
Once the flame rod proves ignition the Infinity modulates by controlling the gas rate, combustion air, and water flow to
precisely heat the water. This control is done by measuring the outgoing water temperature with a Thermistor.
Standby
When the hot water tap is closed the PCB no longer receives a pulse signal from the water flow sensor. The PCB shuts
the main solenoid valve and change-over solenoid valves and the burner extinguishes.
Modulating Solenoid
Valve
Main Solenoid Valve
AC230V/50Hz
Over Heat Switch
Remote Controller
Water Flow
Control Device
Frost Sensing
Thermistor
Solenoid Valve SV1
Solenoid Valve SV2
Water Flow
Control Device
Spark
Electrode
Flame Rod
Igniter
(INCLUDED 5A FUSES)
P.C.B P.C.B
Burner
Exhaust Duct
Flue Outlet
By-pass Mixing
Outgoing Water
Thermistor
(TWIN Type)
Anti-Frost Heater
Pressure Relief
Valve
Water Filter
And Drain
Gas
Hot Water
Outlet
Water
Inlet
Water Flow
Sensor
Combustion Fan
Heat Exchanger
Thermal Fuse
(Code Type)
Heat Exchanger
Water Thermistor
(Lime Sensor)