Rinnai REU-16 User manual

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The Rinnai Infinity 16i water
heater, when correctly installed,
complies with the requirements
of the United Kingdom Water
Regulations / Byelaws
(Scotland). These Products can
be found listed in the Water Fit-
tings and Materials Directory.
The Rinnai Infinity 16i water heater
is CE Marked as allowed by
Technigas.
Certificate number E0940/5399
ID number 0461BQ0836
Date of Issue 23 Dec 2005
Quality System Standard
ISO 9001 - 1994
The Design, Development, and Manufacture of Gas Water Heating Appliances
done under Rinnai’s Quality Management System is certified under the Quality
Management System Standard ISO 9001.
Registration Number JQ0003D
Registered since: February 1994
Certified by Japan Gas Appliances Inspection Association.

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This appliance may only be serviced or repaired by someone certified competent to
do so. At the time of printing the only people deemed competent to install this
appliance are those that are CORGI registered for this type of appliance in this type
of location who have a current ACS certificate.
1. Gas safety (Installation & Use) regulations 1998 are the ‘Rules in force’. In your own
interest and that of safety, it is law that all gas appliances are installed and serviced by
competent persons in accordance with the above regulations. Failure to install appliances
correctly could lead to prosecution. Other persons should NOT attempt to install this
equipment.
2. Installation must be in accordance with the current issue of the following:
Building Regulations issued by the Department of the Environment
Building Standards (Scotland) Regulations.
I.E.E. Wiring regulations for electrical installations.
Gas safety (Installation and Use) Regulations current issue.
BS 5546
BS 5440
BS 6891
BS 5482
BS 6700
BS 6644
Institute of Gas Engineers Publications
Local byelaws
Water regulations
Health and safety at work etc. Act 1974
IGE/UP/10 Part1 Edition 2.
Building Regulation J
Please be sure that you are fully aware of your obligations and responsibilities under
these regulations.
UK INSTRUCTIONS
Such other specifications
and regulations that may
supersede or complement
the above documents.

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Contents………………………………………………………………..…………………4
Glossary of Terms and Symbols.............................................................................5
Introduction.............................................................................................................6
Specification of 16i..................................................................................................7
Sensors and Safety Devices..................................................................................8
Combustion Specifications.....................................................................................8
Dimensions.............................................................................................................9
Schematic Diagram..............................................................................................10
Structure Diagram.................................................................................................11
Main Components.................................................................................................12
Water Flow............................................................................................................14
Water Pressure vs. Flow.......................................................................................16
Gas Conversion Procedure..................................................................................17
Testing..................................................................................................................19
Gas Pressure Setting............................................................................................20
Dip Switch Setting.................................................................................................22
Troubleshooting the Infinity 16i.............................................................................23
Remotes...............................................................................................................24
Operational Flow Chart.........................................................................................25
Time Charts..…………………………………………………………………......…….26
Error Codes.........................…………………………………………………….....….27
Diagnostic Checks………............……………………………………………............29
Fault Finding Chart…………………………...........................………………………39
Wiring Diagram..……………………………………............………………...............46
Diagnostic Points….………………………………………………......………..……...47
Servicing Procedure…….……………………………………………………………..48
Dismantling for Service……………………………………………………………......49
Exploded Diagram................................................................................................56
Parts List...............................................................................................................61
Letter of Compliance……………………………………………………....….............65
CE Certificate……………………………..……………………………………............66
Service Contact……………………………….…………………………….........……67
Contents

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Glossary of Terms and Symbols

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Introduction
The Rinnai Infinity hot water units represents the latest
technology in continuous flow, temperature controlled hot water.
Features
• The Rinnai Infinity 16i will NEVER RUN OUT of hot water. As long as electricity,
water, and gas supplies are connected, hot water is available when hot water taps
are open.
• Built into the main micro-processor is the facility to LIMIT THE MAXIMUM TEM-
PERATURE of the hot water supplied. The water temperature may be set to vari-
ous temperatures. This is particularly useful when the hot water unit is installed
where young children or the infirm may be using the hot water. If required, the tem-
perature can be changed via the control pad on the front of the unit or with a local-
ised controller. For further information, please contact Rinnai.
• Rinnai Infinity internal units are powered flue appliances. This makes them COM-
PACT, saving both floor and wall space.
• The temperature of outgoing hot water is CONSTANTLY MONITORED by a
BUILT-IN SENSOR. If the temperature of the outgoing hot water rises to more than
55°C the burner is shut OFF and only turned ON again when the temperature falls
to below the selected temperature.
• The burner lights automatically when the hot water tap is opened, and extinguishes
when the tap is closed. IGNITION IS ELECTRONIC, so there is no pilot light. When
the hot water tap is off, no gas is used.
• The 16i has a built in controller on the front of the unit for easy control. Two addi-
tional external temperature controllers can be mounted remotely from the heater.
This offers the following additional features:
Localised temperature setting.
Diagnostic message.
Error Codes.
• Temperatures selected at the controllers are retained in the SYSTEM MEMORY
when the controller gives up priority or the system is turned off. Temperatures over
550C will revert to 550C when power and/or priority is regained.
• Operating NOISE LEVEL IS VERY LOW.
• ERROR MESSAGES ARE DISPLAYED on the Temperature Controllers, assisting
with service.
• FROST PROTECTION device built in as standard.

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Specification of 16i
Type of Appliance Temp Controlled Continuous Flow Gas Water Heater
Operation With / Without remotes (Kitchen, Bathroom, etc.)
Flue System Room Sealed, Forced Draught Flue
Installation Internally Mounted only
Available Temps 37C - 48C (1 deg Increments) 50, 55, 60
Width 370 mm
Dimensions Height 675 mm
Depth 130 + 45 mm
Weight 15 kg
Gas 1/2 in bsp
Connections Cold Water 1/2 in bsp
Hot Water 1/2 in bsp
Ignition System Direct Electronic Ignition
Noise Level 49 dB(A)
Nox 55 ppm Max
Water Temp Control Simulation feed forward and feedback
Flame Failure Flame Rod
Boil Dry Water Flow Sensor
Remaining Flame 97 C bimetal switch
Safety Devices Over current Glass Fuse 3 Amp
Over pressure Pressure Relief Valve 15 bar open, 12 bar close
Combustion Fan Integrated circuit system
Fusible Link 150 C Thermal Fuse
Over temperature Lockout Thermistor 95 C
Heater Mounted MC-45-SR-EU
Remote Controls Kitchen BC-45-SR-EU or BSC-45-SR-EU
Bathroom BC-45-SR-EU or BSC-45-SR-EU
Remote Cable Two core sheathed (double insulated) flex with min 0.55 mm2
G20 Nat Gas Press Low 1.8 mbar
G20 Nat Gas Press High 9.0 mbar
G25 Nat Gas Press Low 1.8 mbar
G25 Nat Gas Press High 9.0 mbar
G30 LPG (Butane) Press Low 2.2 mbar
G30 LPG (Butane) Press High 11.4 mbar
G31 LPG (Propane) Press Low 2.2 mbar
G31 LPG Propane) Press High 14.2 mbar
Gas Consumption Low (Gross)
G20 Nat Gas 4.7 kW 0.4 m3/hr
G25 Nat Gas 4.0 kW 0.4 m3/hr
G30 LPG (Butane) 4.9 kW 0.35 kg/hr
G31 LPG (Propane) 4.9 kW 0.35 kg/hr
Gas Consumption High (Gross)
G20 Nat Gas 34.9 kW 3.26 m3/hr
G25 Nat Gas 29.6 kW 3.26 m3/hr
G30 LPG (Butane) 36.8 kW 2.6 kg/hr
G31 LPG (Propane) 36.5 kW 2.6 kg/hr
Max Flow raised 25C 15.2 L/min
Min Operation Flow 2.4* L/min
Water Pressure Nom. 1.1 - 7.0 bar
Power Supply 230 V / 50 Hz
Electric Consumption 68 Watts

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• Heat Exchanger Thermistor: Measures hot water temperature at heat exchanger outlet. If
water temperature reaches a predetermined limit, gas supply is stopped.
• Hot Water Delivery Thermistor: Measures hot water temperature at the outlet valve (i.e. the
‘mixed’ temperature).
• Flame Rod: Monitors combustion characteristics inside the combustion chamber. If the flame
fails, gas supply is stopped.
• Overheat Switch: Situated on the heat exchanger, gas supply is stopped when water
temperature reaches 97ºC for a number of seconds.
• Fusible Link: Situated on the heat exchanger, electrical power supply is stopped if the
temperature exceeds 150ºC.
• Water Pressure Relief Valve: Safeguards the water circuit against excessive inlet pressure.
Opens at 15 bar, closes at 12 bar.
• Electrical Fuse: (3A glass fuse) prevents against over-current. Surge Protector: prevents
against over-current.
• Boil Dry Prevention: If water flow sensor detects no flow, gas supply is stopped.
• Combustion Fan Speed Sensor: In case of combustion fan defect (no rotation of fan) gas
supply is stopped.
• Temperature Cutout: If the delivered hot water temperature rises above the required delivery
temperature for a number of seconds, the gas supply is stopped.
Sensors and Safety Devices
Combustion Specifications
The secondary gas pressure is set with the cover off the unit and a manometer measuring
the pressure from the gas valve (regulator) test point
Gas Type
Injector
size
(mm)
Primary
Pressure (mbar)
Secondary Pressure
(mbar)
Gas Input [Gross]
(kW)
Low High Low High
Natural Gas
(G20) 1.3 20 1.8 9.0 4.7 34.9
Propane (G31) 37 2.2 14.2 4.9 36.5
Damper
Nat Gas
LPG

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Dimensions

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HOT WATER SUPPLY OPERATION
Ignition
Press ON/OFF Button of Optional Remote Control to turn on unit . The remote control 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 a water
flow over 2.4 L/min it compares the temperature at the Hot Water Thermistor to the set point
and begins the ignition process; the Combustion Fan starts first. Once the chamber has been
purged and the air proving has made the Electrode begins to spark to Earth. The Main
Solenoid Valve and Changeover Solenoid Valve 2 are opened and the Burner lights. The
Flame Rod will ensure proper burning before Changeover Solenoid Valve 1 will open.
Temperature Setting
With the Temperature Control Buttons on the controller the outlet temperature can be set from
37 - 60℃. When the temperature set point is above 50℃the High Temperature Indicator
glows. Temperature can not be set above 48℃while hot water is in use (flowing.) The unit will
continually monitor the outgoing temperature and can fully modulate the performance with the
Modulating Valve and the Servo Control.
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. The combustion fan will run on to post purge the chamber.
Schematic Diagram