Rinnai REU-VR2626W Series User manual

SERVICE MANUAL
To Suit Models:
Does NOT Suit any other Models
REU-VR2626WB (B26)
REU-VR2426WS (S26)
REU-VRM2626WG (INF26)

All Rinnai products are certified by the
Australian Gas Association as compliant
to relevant Australian Standards.
All Rinnai products are Certified to
WaterMark by SAI Global. WaterMark
certification is awarded to products and
fittings complying with safety and water
contamination standards.
SAI Global

© Copyright Rinnai Australia Pty Ltd ABN 74 005 138 769
All rights reserved
Produced by Engineering & Technical Group
No portion or part of this manual may be copied without prior
permission from Rinnai Australia.
Rinnai Australia 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 Australia Engineering &
Technical Group.
We welcome users of this manual to provide feedback and suggestions
for improvement purposes.
W A R N I N G
• All wiring inside this appliance my be at 240 Volts potential.
• All service work must be carried out by an authorised person.
REU-VR2626WB (B26)
REU-VR2426WS (S26)
REU-VRM2626WG (INF26)
WARNING
WARNING

REU-VR2626WB (B26) /REU-VR2426WS (S26) /REU-VRM2626WG (INF26) - 1 - Issue 3 - 13/11/14 ©Rinnai
Table of Contents
Glossary of Terms and Symbols ................................................................................. 2
1. Specifications ............................................................................................................. 3
2. Water Flow Rates and Pressure Characteristics ........................................................ 6
3. Dimensions ................................................................................................................ 7
4. Water Controllers ....................................................................................................... 8
5. Cutaway Diagram .................................................................................................... 10
6. Smartstart ................................................................................................................. 11
7. Operational Flow Chart ........................................................................................... 13
8. Operation Principles ................................................................................................ 14
9. Main Components .................................................................................................... 15
10. Time Charts ............................................................................................................ 16
11. Wiring Diagram ..................................................................................................... 17
12. Dip Switch Settings ............................................................................................... 18
13. Fault Finding .......................................................................................................... 19
14. Component and Circuit Checks ............................................................................. 21
15. Maintenance Monitor / Error History .................................................................... 25
16. Gas Pressure Setting Procedure ............................................................................. 27
17. Gas Conversion Procedure ..................................................................................... 27
18. Dismantling for Service ......................................................................................... 28
19. Parts List ................................................................................................................ 37
REU-VR2626WB .............................................................................................................38
REU-VRM2626WG..........................................................................................................40
REU-VR2426WS ..............................................................................................................42
20. Exploded Diagrams ................................................................................................ 45

REU-VR2626WB (B26) /REU-VR2426WS (S26) /REU-VRM2626WG (INF26) - 2 - Issue 3 - 13/11/14 ©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
kPa - kilopascals
LED - light emitting diode
L/min - Litres per minute
mA - milliamps
MJ/h - megajoule per hour
mm - millimetres
mmH2O - millimetres of water (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


REU-VR2626WB (B26) /REU-VR2426WS (S26) /REU-VRM2626WG (INF26) - 3 - Issue 3 - 13/11/14 ©Rinnai
1. Specifications
Rinnai Model Number REU-VR2426WS
Type of appliance Temperature controlled continuous flow gas hot water system
Exhaust system Fan Forced
Installation External
Dimensions Width - 350 mm
Height - 530 mm
Depth - 194 mm
Weight 16 kilograms
Gas consumption (Min. / Max.) Natural gas: 23~188 MJ/hr
Propane gas: 23~188 MJ/hr
Output (kW) (Maximum) 42 kW
Connections Gas connection - R3/4 (20A)
Cold water connection - R3/4 (20A)
Hot water connection - R 3/4 (20A)
Ignition system Direct electronic ignition
Electrical consumption Normal - 45 W
Standby - 2 W (with 1 water control)
Anti-frost protection - 90 W
Delivery temperatures 40°C, 42°C, 50°C, 55°C, 60°C, 65°C, 75°C (set by combination of dip
switches on PCB) NOTE: 2426WS must be preset to 70°C.
Water flow control Water flow sensor, electronic water flow control device.
Maximum hot water capacity raised
@ 25°C 24 L/min
Water pressure required to achieve
maximum hot water capacity 140 kPa
Maximum water flow 26 L/min.
Water pressure required to achieve
maximum water flow 180 kPa
Minimum water flow for operation 2.4 L/min.
Power supply Appliance - AC 240 Volts 50 Hz
Water controller - DC 12 Volts
Water controllers (optional) Water controllers not compatible with REU-V2426WS
Water Controller Cable Cables are supplied with water controllers. Alternatively, two core sheathed
(double insulated) flex with minimum cross sectional area of 0.5 m² may be
used. Maximum individual cable runs should not exceed 50 m.

REU-VR2626WB (B26) /REU-VR2426WS (S26) /REU-VRM2626WG (INF26) - 4 - Issue 3 - 13/11/14 ©Rinnai
Rinnai Model Number REU-VRM2626WG / REU-VR2626WB
Type of appliance Temperature controlled continuous flow gas hot water system
Exhaust system Fan Forced
Installation External
Dimensions Width - 350 mm
Height - 530 mm
Depth - 194 mm
Weight 16 kilograms
Gas consumption (Min. / Max.) Natural gas: 23~199 MJ/hr
Propane gas: 23~199 MJ/hr
Output (kW) (Maximum) 45 kW
Connections Gas connection - R3/4 (20A)
Cold water connection - R3/4 (20A)
Hot water connection - R 3/4 (20A)
Ignition system Direct electronic ignition
Electrical consumption Normal - 45 W
Standby - 2 W (with 1 water controller)
Anti-frost protection - 90 W
Delivery temperature 40°C, 42°C, 50°C, 55°C, 60°C, 65°C, 75°C
(set by combination of dip switches on PCB)
Water flow control Water flow sensor, electronic water flow control device
Maximum hot water capacity raised @
25°C 26 L/min
Water pressure required to achieve
maximum hot water capacity 180 kPa
Maximum water flow 26 L/min.
Water pressure required to achieve
maximum water flow 180 kPa
Minimum water flow for operation 2.4 L/min.
Power supply Appliance - AC 240 Volts 50 Hz
Water controller - DC 12 Volts
Water controllers (optional) A maximum of 4 water controllers can be fitted. Any combination of
deluxe, universal and wireless controllers can be used with the following
limitations:
Only ONE master controller can be installed. This can be a MC-100V, a
MC-91Q (when programmed as a mater controller) a MC-503RC water
controller.
Up to TWO BC-100V water controllers can be installed.
The FOURTH water controller in any installation MUST be a
MC-503RC or a MC-91Q.
Water Controller Cable Cables are supplied with water controllers. Alternatively, two core
sheathed (double insulated) flex with minimum cross sectional area of 0.5
m² may be used. Maximum individual cable runs should not exceed 50 m.

REU-VR2626WB (B26) /REU-VR2426WS (S26) /REU-VRM2626WG (INF26) - 5 - Issue 3 - 13/11/14 ©Rinnai
Sensors and Safety Functions
•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
2060 kPa, closes at 1470 kPa.
•Electrical Fuse: (3A glass fuse) prevents against power surges.
•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 blades) 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
Refer to dataplate on appliance.

REU-VR2626WB (B26) /REU-VR2426WS (S26) /REU-VRM2626WG (INF26) - 6 - Issue 3 - 13/11/14 ©Rinnai
2. Water Flow Rates and Pressure Characteristics
Water flow rate and pressure characteristics are shown below.
Water Flow vs Pressure Graphs
26.5
0
5
10
15
20
25
30
35
0 50 100 150 200 250 300
Inlet pressure (kPa)
Outlet flow (litres/minute)
2426/2626

P(kPa) 0 10 20 30 40 50 60 70 80 90
4/PLQ  5.3 8 10.3 12.1 13.8 15.6 17 18.2 19.4
 %36IXOOFORVH
 %36IXOORSHQ

P(kPa) 100 110 120 130 140 150 160 170 200 300
4/PLQ 20.4 21.4 22.1 23 24.2 25 25.5 26 26.5 26.5
 %36IXOOFORVH
 %36IXOORSHQ

REU-VR2626WB (B26) /REU-VR2426WS (S26) /REU-VRM2626WG (INF26) - 7 - Issue 3 - 13/11/14 ©Rinnai
3. Dimensions
Dim' Description
REU-VRM2626WG
AWidth 350
BDepth 194
CHeight - Unit 530
DHeight - Including Brackets 571
EHot Water outlet (from wall) 87
FHot Water outlet (from centre) 105
GCold Water inlet (from wall) 68
HCold Water inlet (from centre) 10
IGas Connection (from wall) 77
JGas Connection (from centre) 83
Gas: Length (from base) 40
Cold: Length (from base) 50
Hot: Length (from base) 42
Gas: Fitting Diameter 20
Cold: Fitting Diameter 20
Hot: Fitting Diameter 20
K
L
BC-100V
MC-100V
MC-91Q
90
120
83
120104
128
202
202022
181
B
D
C
K
A
E
FJ
H
I
G
L
FITTING
DIAMETER
* Please note that this measurement is to the left of the centre line.
83
REU-VR2426WS REU-VR2626WB