Rinnai INFINITY 26i User manual

INFINITY 26i and HD50i
Infinity High Capacity Continuous Flow Gas Hot Water System
SERVICE MANUAL

The Rinnai Infinity 26i and
Heavy Duty 50i water heater,
when correctly installed, comply
with the requirements of the
United Kingdom Water Regula-
tions / Byelaws (Scotland).
These Products can be found
listed in the Water Fittings and
Materials Directory.
The Rinnai Infinity 26i water heater
is CE Marked for UK and Ireland as
allowed by Technigas of Belgium.
Certificate number E0716/5360
ID number 0461BO0739
Date of Issue 28 July2003
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.

Produced by Rinnai Technical Services Department
August 2004- Issue 1.
No portion orpart of this manual may becopied without prior permission from Rinnai U.K.
Rinnai U.K. reserves the right to make modifications and change specifications without notice.
Failure to comply with these instructions may result in serious personal injury or damage to the
appliance.
This manual has been published by Rinnai U.K. Technical Services. While many individuals
have contributed to this publication, it will be successful only if you - the reader and customer -
find it useful. We would like to extend an invitation to users of this manual to make contact with
us, as your feedback and suggestions are valuable resources for us to include as improvements.
Rinnai are constantly working toward supply improved appliances as well as information, and
specifications may be subject to alteration at any time.
Issue No1
WARNING
ALL WIRING INSIDE THIS APPLIANCE MAY BE AT 230 VOLTS POTENTIAL
ALL SERVICE WORK MUST BE CARRIED OUT BY AN AUTHORISED PERSON.
DO NOT TEST FOR GAS ESCAPES WITH AN OPEN FLAME

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - iii - Issue 1 - 8/09/03 ©Rinnai
Table of Contents
Glossary of Terms and Symbols .................................................................................. iv
1. Introduction ................................................................................................................ 1
2. Specifications ............................................................................................................. 2
3. Water Flow Rates and Pressures ................................................................................ 4
4. Dimensions ................................................................................................................ 8
5. Remote Controls ........................................................................................................ 9
6. Cutaway Diagram .................................................................................................... 13
7. Operational Flow Chart ........................................................................................... 14
8. Operation Principles ................................................................................................ 15
9. Main Components .................................................................................................... 16
10. Time Charts ............................................................................................................ 18
11. Wiring Diagram ..................................................................................................... 19
12. Dip Switch Settings ............................................................................................... 20
13. Fault Finding .......................................................................................................... 21
14. Component Circuit Value Tabl.e / and checks........................................................ 23
15. Maintenance Monitor / Error History ................................................................... 31
16. Gas Pressure Setting Procedure ............................................................................ 33
17. Gas Conversion Procedure .................................................................................... 35
18. Dismantling for Service........................................................................................ 44
19. Exploded Diagram ................................................................................................ 50
20. Parts List ............................................................................................................... 54
21. SERVICE CONTACT POINTS .......................................................................... 58

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - iv - Issue 1 - 8/09/03 ©Rinnai
Glossary of Terms and Symbols
dB(A) - sound pressure level in decibels, “A” range
DC - direct current
AC - alternating current
WFCD - water flow control device
FB - feedback information
FF - feedforward information
Hz - Hertz
IC - integrated circuit
kcal/h -kilocalorie per hour
kW -kilowatts
LED - light emitting diode
L/min - Litres per minute
mA - milliamps
mbar -millibars of pressure
mm - millimetres
bar -gauge pressure
OHS - overheat switch
PCB - printed circuit board
CPU - central processing unit
POT - potentiometer
rpm - revolutions per minute
SV - solenoid valve
ø - diameter
oC - temperature rise above ambient
POV - modulating valve
TE - thermal efficiency
TH - thermistor
TIN - temperature of incoming water
TOUT - temperature of outgoing water
∆

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 1 - Issue 1 - 8/09/03 ©Rinnai
1. Introduction
The Rinnai Infinity hot water units represents the latest technology in continuous flow, temperature
controlled hot water.
Features
•The Infinity 26iand HD50i NEVER RUN OUT of hot water.Whilst electricity,water and gas
supplies are connected, hot water is available whenever hot water taps are open.
• Built into the main micro-processor is the facility to LIMIT THE MAXIMUM TEMPERATURE of
the hot water supplied. The water temperature may be limited to various maximum temperatures. This
is particularly useful when the hot water unit is installed where young children or the infirm may be
using the hot water. The Infinity is delivered with a maximum preset temperature of 55 C and the
HD50i at 65° C. If required, the temperature limits can be changed by a service technician. For
further information, please contact Rinnai.
• The Infinity is a power flued appliance. It is COMPACT, 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 3 C above the selected temperature
shown on the Digital Monitor (or the pre-set limit when Remote Controls are not fitted), the burner will
automatically go out. The burner will ignite again once the outgoing hot water temperature falls below
the temperature shown on the Digital Monitor (or the pre-set limit).
• The burner lights automatically when the hot water tap is opened, and goes out when the tap is closed.
IGNITION IS ELECTRONIC, therefore there is not pilot light. When the hot water tap is off, no gas is
used.
• ‘Deluxe’ or ‘Standard’ Remote Controllers are available as an optional extra. Depending on the models
chosen, these offer the following additional features :
- Bath fill function
- Voice Prompting
- Localised Temperature Control for up to four controllers
- Clock
• Temperatures selected at the controllers are retained in the SYSTEM MEMORY.
• Operating NOISE LEVEL IS VERY LOW.
• ERROR MESSAGES ARE DISPLAYED on the Remote Controllers, assisting with service.
°
°

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 2 - Issue 1 - 8/09/03 ©Rinnai
2. Specifications
Note1: The default factory setting is 55ºC for the Infinity26i, and 65°C for HD50i. The unit can be ordered
from Rinnai to be pre-set to any of the other temperatures listed. The unit can be pre-set to any of the
temperatures listed by a suitably qualified person.
Controllers are available with default temperatures up to 75º C. When fitted with controllers, only
temperatures not exceeding the default temperatures can be selected. When fitted without controllers, the
unit will deliver water at the default temperature. Controllers are not available with 85° C settings.
Note 2: Unit will operate at lower pressures but the maximum rated flow of 32L/min. will not be achieved.
Model No. Infinity 26i and HD50i
Type of Appliance Temp.controlled continuous Flow Gas Hot Water Unit
Operation With/without remote controls, mounted in Kitchen, bathroom,etc.
Flue System Room Sealed - Forced Draught Flue
Installation Internally mounted (Indoor Only)
Available Default Temperatures (Note 1):
(without Remote Controllers)
40º C, 43º C, 50º C, 55º C, 60º C, 65º C, 75º C, 85º C
(set by combination of Dip switches on PCB)
Temperature Range (with Remote Controllers) Kitchen controller : 37 ~ 55º C
Bathroom controller : 37 ~ 50º C
Dimensions (mm)
Width 350
Height 600
Depth 224
Weight (Kg) 22
Connections
Gas 3/4in. BSP
Cold Water Supply3/4 in. BSP
Hot Water Supply3/4 in. BSP
Ignition System Direct Electronic Ignition
Max. / Min. Gas
Consumption
Natural Gas 54 -- 4.4 kW
PropaneGas54 -- 4.4 kW
Hot Water Delivery Capacity Max. 26 to 32 L/min.
Noise level 49 dB(A)
Thermal Efficiency 87%
NOXaf 55 ppm Max.
Minimum Operating Water Flow:2.4 L/min.
Minimum Operating Pressure (Note 2): 1.8bar
Maximum Operating Water flow 32 L/min.
Nominal Operat-
ing Pressure
Less than 60°C 1.4bar
Greater than or equal to 60°C 2.0~10.0 bar
Power Supply
Infinity UnitAC 230Volts (50 Hz)
Remote Control (optional) DC 12 Volts (Digital)
Water temperature control Simulation feedforward and feedback
Water flow
control
ElectronicWater flow sensor,flow control & heat exchanger
by-pass flowcontrol.
Safety Device
Flame Failure Flame rod
Boil dry Water flow sensor
Remaining Flame (OHS) 97ºC bi-metal switch
Over temperature 95º C lockout thermistor
Fusible link129º C Thermal Fuse
Pressure relief valve Opens20.6 bar,closes 14.7 bar
Combustion fan rpm check Integrated circuit system
Over current Glass fuse (3 Amp).
Remote
Controllers
(optional)
KitchenMC91-1A orMC-70-2A
Bathroom MC91-1A orBC-70-2A
SecondBathroom MC91-1A orBC-70-2A
Third Bathroom MC91-1A
Remote Controller Cable (Optional) Two core sheathed (double insulated) flex with min.cross-sectional area of 0.5 mm²
Electrical
Consumption
Normal 80W
Standby 7.5 W (with 1 Remote Control)
Manifold Electronic Control System (Optional) MSA-2M, MSA-2S

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 3 - Issue 1 - 8/09/03 ©Rinnai
Sensors and Safety Devices
• 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 129ºC.
• Water Pressure Relief Valve: Safeguards the water circuit against excessive inlet pressure. Opens at
20.6bar, closes at 14.7 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.
Combustion Specifications
* * The TPP is measured with the cover ‘off’ the appliance at the regulator test point with supply pressures
of 20 mbar (NG) and37 mbar (Propane).
Gas Type Injector
Size (mm)
Upper /
Lower
Nominal TPP (mbar)* * Gas Input (kW)
Low High Low High
Natural
1.00
1.98.54.4 54
1.7
Propane 0.75
2.310.8 4.4 54
1.15

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 4 - Issue 1 - 8/09/03 ©Rinnai
3. Water Flow Rates and Pressures
Water Flows
Table 1 shows unmixed and mixed water flow rates and approximate gas consumptions for various
temperature rises. The unmixed flow rates are the flow rates available at the given temperature rise directly
at the outlet of the water heater. The mixed water flow rates are available at the given temperature rise by
mixing hot water from the outlet of the water heater with cold water from the mains supply.
Water Flows can also be calculated by the following formula:
M = 60 x ( Q / C x T )
Where M = Water flow rate in litres/minute. If M is ≤ to 26, the water is unmixed. If M is > 26, the water
is mixed.
Q=Heat energy output in kW = 47kW for theInfinity 26i and HD50i
C = Specific heat of water = 4.2KJ/Kg C. C does not change for the purpose of this calculation.
T = Temperature rise required ( C)
Example:
What is the flow rate available with an incoming water temperature of 10 C and a required temperature of
20 C?
T = 20 - 10 = 10 C
Q = 47
C = 4.2
M = 60 x ( 47 / (4.2 x 10) ) = 67 l/min. Since 67 is greater than 26 this flow rate is mixed. This result
corresponds with the value in Table 1.
Table 1: ApproximateWater Flows & Gas Usage - Rinnai Infinity 26i and HD50i - Preset Table
∆
°
∆°
°
°
∆°

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 5 - Issue 1 - 8/09/03 ©Rinnai
Table 1. Approx.Water Flows & Gas Usage - Rinnai 26i and HD50i Preset Temp. Less than 60°C.
Temp Rise
(º C)
Approx.
Min / Max
Gas Input
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Infinity 26 i and HD 50i
4.4-54 0.53 32 1920 1.4 13 0.53 32 1920 1.4 26 0.53 32 1920 1.4 39 0.53 32 1920 1.4 52
Temp Rise
(º C)
Approx.
Min / Max
Gas Input
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Infinity 26 i and HD 50i
4.4-54 0.44 26.4 1584 1.0 54 0.37 22.2 1332 0.65 54 0.32 19.2 1152 0.5 54 0.28 16.8 1008 0.4 54
Temp Rise
(º C)
Approx.
Min / Max
Gas Input
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Infinity 26 i and HD 50i
4.4-54 0.25 15 900 0.3 54 0.22 13.2 792 0.25 54 0.2 12 720 0.23 54 0.19 11.4 684 0.2 54
Temp Rise
(º C)
Approx.
Min / Max
Gas Input
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Infinity 26 i and HD 50i 4.4-54 0.17 10.2 612 0.19 54 0.16 9.6 576 0.18 54 0.15 9 540 0.17 54 0.14 8.4 504 0.16 54
Models (Preset temps
less than 60 C)
20
30 35 40 10 15 50 55 60
65 70 75 80
Models (Preset temps
less than 60 C)
25
Models (Preset temps
less than 60 C)
45
5
Models (Preset temps
less than 60 C)

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 6 - Issue 1 - 8/09/03 ©Rinnai
Approx.Water Flows & Gas Usage -Rinnai Infinity26i and 50i Preset Temp.Greater thanor equal to 60°C
Temp Rise
(
ºC
)
Approx.
Min/Max
Gas Input
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Infinity 26 i and HD 50i 4.4-54 0.4 24 1440 2.0 10 0.4 24 1440 2.0 20 0.4 24 1440 2.0 30 0.4 24 1440 2.0 40
Temp Rise
(º C) L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Approx.
Min / Max
Gas Input
kW
Infinity 26 i and HD 50i 4.4-54 0.4 24 1440 2.0 50 0.37 22.2 1332 1.1 54 0.32 19.2 1152 0.8 54 0.28 16.8 1008 0.6 54
Temp Rise
(
ºC
)
Approx.
Min/Max
Gas Input
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Infinity 26 i and HD 50i 4.4-54 0.25 15 900 0.5 54 0.22 13.2 792 0.4 54 0.2 12 720 0.4 54 0.19 11.4 684 0.3 54
Temp Rise
(
ºC
)
Approx.
Min/Max
Gas Input
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
L/sec L/min L/hr
Min Water
Pressure
bar
Approx
Gas
Cons.
kW
Infinity 26 i and HD 50i 4.4-54 0.17 10.2 612 0.354 0.16 9.6 576 0.3 54 0.15 9540 0.27 54 0.14 8.4 504 0.25 54
Models (Preset temps greater
than or equal to
60 C)
10 15 20
25
5
50 55 60
65 70 75 80
30 35
Models (Preset temps greater
than or equal to
60 C)
40
Models (Preset temps greater
than or equal to
60 C)
45
Models (Preset temps greater
than or equal to
60 C)

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 7 - Issue 1 - 8/09/03 ©Rinnai
Water Pressure
The waterpressure vs flow characteristics are as follows:
WATER PRESSURE/FLOW RATE
0
5
10
15
20
25
30
35
 1.0 2.0 3.0 4.0
WATER PRESSURE(bar)
WATER FLOW RATE (L/min)
INFINITY 26i AND HD50i웛37ദ-55ദ

INFINITY 26i AND HD50i:60ദ& Higher

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 8 - Issue 1 - 8/09/03 ©Rinnai
4. Dimensions

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 9 - Issue 1 - 8/09/03 ©Rinnai
120
90
20
MC-91-1A
195
97
22
BC-70-2A
5. Remote Controls
Remote Controls
Remote Controllers are an optional extra. 'Standard' and 'Deluxe' controllers can be
fitted.
Standard controllers allow temperature selection only. Deluxe controllers have
temperature selection, bath-fill and voice prompting functions. For detailed
information regarding controller operation refer to the 'How to use your water
heater' booklet supplied with the appliance. Other manufacturers' controllers are
NOT compatible with this appliance.
Standard Controller (Model MC-91)
Up to 4 Standard Controllers can be fitted to the appliance. They are normally
installed in the areas where the majority of hot water is used, for example, the
kitchen, bathroom, ensuite and laundry.
Deluxe Kitchen Remote Control (MC-70) and (BC-70A)
Deluxe controllers have 'Kitchen' (MC-70-2A) and 'Bathroom' (BC-70-2A) versions. 'Kitchen' controls are
intended for the Kitchen or other convenient area where the majority of hot water is used. Bathroom
Controllers are intended to be fitted in the bathroom or ensuite and allow the user to have a bath filled to
the required level and temperature automatically.
:
Positioning of Controllers
Controllers must be installed in shaded and clean locations. They should be fitted out of reach of children
(suggested height from floor at least 1500mm). Controllers are water resistant, however, durability is
improved when positioned outside the shower recess or at least 400mm above the highest part of a sink,
basin or bath.
Up to three ‘Deluxe’ Controllers
can be connected
If a fourth Controller is required a ‘Standard’
Controller can be included
Kitchen Bathroom Ensuite Kitchen Bathroom Ensuite Laundry
MC70-2A MC70-2A
MC70-2A MC70-2A
MC70-2A BC70-2A MC70-2A BC70-2A
MC70-2A BC70-2A BC70-2A MC70-2A BC70-2A BC70-2A MC91-1A

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 10 - Issue 1 - 8/09/03 ©Rinnai
DO NOT INSTALL THE CONTROLLERS
• NEAR A HEAT SOURCE, SUCH AS A COOK TOP, STOVE OR OVEN. HEAT, STEAM,
SMOKE AND HOT OIL MAY CAUSE DAMAGE
• IN DIRECT SUNLIGHT
• OUTDOORS UNLESS AN ENCLOSURE IS PROVIDED WHICH PROTECTS THE
CONTROLLER AGAINST SUNLIGHT AND DUST INGRESS.
•AGAINST A METALWALL UNLESS THE WALL IS EARTHED IN ACCORDANCE
WITH CURRENT REGULATIONS.
Remote Controller Connection
Remote controls operate atextra low voltage (12 Volts DC) which is supplied from the appliance.
Controllers are supplied with 15 m of electrical cable.The cable wires for connection to the appliance are
fitted with spade terminals.
Extension cables are available from Rinnai. Alternatively, a two core sheathed (double insulated) flex with
minimum cross-sectional area of 0.5 mm² can be used. Maximum cable length is 50 m.
For connection refer to the “CONNECTING REMOTE CONTROL CABLES” section.
If the front cover of the appliance contains the following text install it in accordance with Diagram 1 below:
Water Heater and Controller installation configurations
If the front cover of the appliance does NOT contain the above text install it in accordance with Diagram 2:
IMPORTANT: If the appliance is to deliver water primarily for the purposes of personal hygiene in an
early childhood centre, primary or secondary school, nursing home or similar facility for young, aged, sick
or disabled persons aTemperature Limiting Device (TLD), such as a Thermostatic Mixing Valve,
may be required even if the appliance is set to 50ºC or less. For these types of applications contact
Rinnai UK.
50º C
KITCHEN
Temperatur
e
controller
(optional)
Temperatur
e
controller
(optional)
Temperatur
e
controller
(optional)
Temperatur
e
controller
(optional)
LAUNDRY
BATHROOM
ENSUITE
H
O
T
C
O
L
D
G
A
S
Diagram 1. Max. 50º C Appliance
KITCHEN
Temperature
controller
(optional)
Temperature
controller
(optional)
LAUNDRY BATHROOM
Temperature
controller
(optional)
Temperature
controller
(optional)
ENSUITE
TLD
H
O
T
C
O
L
D
G
A
S
Diagram 2. Not a 50º C Appliance
Note: TLD = Temperature Limiting Device Recommended.

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 11 - Issue 1 - 8/09/03 ©Rinnai
Connecting remote control cables
Do not attempt to connect the remote control cable terminals to the appliance with the power on.
RISK OF ELECTRICAL SHOCK.
Connecting One or Two Controllers
1. Isolate the power supply
2. Remove the front cover from the Appliance (4 screws) fig. 1.
3. Thread the cable(s) through the cable access hole at the base
of the appliance.
4. Connect the spade connectors to the terminals marked
"Remote Control" on the printed circuit board (fig. 2).
Polarity is not important. Either wire colour can be
connected to either terminal.
5. Replace cover of the Appliance. Ensure that the screw with
the star washer is placed at the bottom right hand corner for
earthing purposes.
Connecting Three Controllers
6. Isolate the power supply
7. Remove the front cover from the Appliance (4 screws) fig.1.
8. Thread the cables through the cable access hole at the base of
the appliance.
9. Connect the 4 spade connectors to the terminals marked
"Remote Control" on the printed circuit board (fig. 2).
Polarity is not important. Either wire colour can be connected
to either terminal.
10.Replace cover of the Appliance. Ensure that the screw with
the star washer is placed at the bottom right hand corner for
earthing purposes.
Connecting Four Controllers
11.Isolate the power supply
12.Remove the front cover from the Appliance (4 screws) fig 1.
13.Cut the spade connectors from all four controller cables to be
connected to the appliance (8 spade connectors should be cut
off) and discard. Connect the wires from two cables and
terminate into two new spade connectors as shown in (fig. 3).
Repeat for the remaining two cables. Spade connectors are
available from your local electrical component retailer.
14.Thread the 4 cables through the cable access hole at the base
of the appliance. Connect the 4 spade connectors to the
terminals marked "Remote Control" on the printed circuit
board (fig 2). Polarity is not important. Either wire colour
can be connected to either terminal.
15.Replace cover of the Appliance. Ensure that the screw with
the star washer is placed at the bottom right hand corner for
earthing purposes.
fig.1
fig.2
fig. 3
New spade connectors
Cable
wires Cable
wires
Remote control cables

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 12 - Issue 1 - 8/09/03 ©Rinnai
MC-91A Controller Programming
Question 1: Are four Controllers connected ?
IF YES: You will need to activate the fourth controller.
STEP 1:
For the Controller in the ‘KITCHEN’ only, press and hold the
‘Transfer’ and ‘On/Off’ buttons simultaneously (see fig. 1) until a
‘beep’ is heard (approximately 5 seconds).
STEP 2:
Check that the display on ALL FOUR controllers is lit and
displaying a temperature when ‘switched on’. If any ONE of the
controller displays two dashes (see fig. 2) in the display repeat
STEP 1.
This completes the activation procedure. Ignore Question 2.
IF NO: (You have three controllers or fewer), go to Question 2.
Question 2: Does your kitchen controller temperature go higher than 50 deg C?
IF YES: No further action required.
IF NO: You will need to program the Kitchen controller to enable selection of temperatures higher than
50º C.
STEP 1:
For the controller in the KITCHEN only, press and hold the 'Transfer' and 'On/Off' buttons
simultaneously (see fig 1.) until a 'beep' is heard (approximately 5 seconds).
STEP 2:
When the controller fitted in the KITCHEN is switched on, it should be possible to select temperatures
higher than 50º C. If not, repeat Step 1.
Note:
•If the kitchen controller is replaced, repeat STEP 1 above for the replacement controller.
• If the kitchen controller is swapped with another controller (for example, the controller fitted
in a bathroom), repeat STEP 1 for the controller moved from the kitchen to the bathroom.
Then perform STEP 1 for the controller moved from the bathroom to the kitchen.
Fig 2.

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 13 - Issue 1 - 8/09/03 ©Rinnai
6. Cutaway Diagram

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 14 - Issue 1 - 8/09/03 ©Rinnai
7. Operational Flow Chart

Infinity REU-V2632FFU / HD200I REU-V2632FFUC - 15 - Issue 1 - 8/09/03 ©Rinnai
8. Operation Principles
Hot Water Operation
1. Ignition
•Activate controllers (if fitted) and open the hot water tap (for full details regarding operation of
controllers refer to the ‘installation and user manual.
• When water flows through the unit, the water flow sensor rotates and sends an electrical ‘pulse’ signal
to the Printed Circuit Board (PCB). This signal is proportional to the water flow rate.
• The PCB sends electrical current to the combustion fan motor causing it to turn. The fan motor sends
an electrical pulse signal to the PCB. If fan rotation is OK, the main solenoid and changeover solenoid
valves open as required, the spark generator activates and the spark electrode ignites the burner.
2. Water Temperature / Flow Control / Volume Control
• The PCB will automatically control operation of the internal components to achieve the programmed
temperature. When a high temperature rise is required, the PCB may cause the Water Flow Servo to
close partially resulting in a lower flow rate to achieve the programmed temperature. This is a
necessary operational feature of the unit.
• When operating in ‘Bath Fill’ mode, the signal from the water flow sensor is also used by the PCB to
compute the volume of water that has been passed through the unit at any instant whilst the bath is
filling.
3. Shut Down
• When operating in ‘Bath Fill’ mode, the PCB causes the Water Flow Servo to close when the
programmed Bath Fill volume has passed through the unit. Alternatively, flow is stopped when the
user closes the hot water tap.
• When water flow stops, the water flow sensor stops rotating and the pulse signal to the PCB stops. The
PCB then causes the main solenoid and solenoid valves to close and the burner is extinguished. The
combustion fan will continue to operate for some time to purge the combustion chamber.