Rinnai REU-2018W Service Manual

Compact continuous flow gas hot water system

Hide thumbs

Table of Contents

Quick Links

INFINITY

REU-2018W

REU-2020W

REU-2422W

REU-2425W

SERVICE MANUAL

Infinity Compact Continuous Flow Gas Hot Water System

Table of Contents

Chapters

Table of Contents

Need help?

Do you have a question about the REU-2018W and is the answer not in the manual?

Questions and answers

Summary of Contents for Rinnai REU-2018W

Page 1 INFINITY REU-2018W REU-2020W REU-2422W REU-2425W SERVICE MANUAL Infinity Compact Continuous Flow Gas Hot Water System...
Page 2 All Rinnai products are certified by the Australian Gas Association as compliant to relevant Australian Standards. Rinnai Australia Head Office is certified as complying with ISO 9001 by SAI Global. Rinnai New Zealand has been certified to ISO 9001 Quality Assurance by Telarc.
Page 3 Produced by Technical Services Department 2004 - Issue 2 No portion or part of this manual may be copied without prior permission from Rinnai Australia. Rinnai Australia takes no responsibility for the accuracy or otherwise of information contained in this manual, and reserves the right to make modifications and change specifications without notice.
Page 4: Table Of Contents
22. Electrical Component Analysis ..............40 23. Gas Conversion ..................43 24. Gas Pressure Setting Procedure .............. 44 25. Dismantling for service ................45 26. Exploded Diagram ..................51 27. Parts list ....................55 Infinity REU-2425W - 1 - Issue 2 - 5/07/04 ©Rinnai...
Page 5 ø diameter ∆ temperature rise above ambient modulating valve thermal efficiency thermistor temperature of incoming water temperature of outgoing water Infinity REU-2425W - 2 - Issue 2 - 5/07/04 ©Rinnai...
Page 6: Introduction
There is one thermistor, it is located on the outgoing hot water supply tube, near the outlet of the heater. Infinity REU-2425W - 3 - Issue 2 - 5/07/04 ©Rinnai...
Page 7: Features
37°C and 43°C while the hot water is flowing. This helps to avoid inadvertently increasing the temperature to a hazardous level whilst someone is in the shower. While the water is flowing, the remote control(s) can be turned off, but not on again. Infinity REU-2425W - 4 - Issue 2 - 5/07/04 ©Rinnai...
Page 9: Remote Controls
(suggested height from floor at least 1500mm). Controllers are water resistant, however, durability is improved when positioned outside the shower recess or at leat 400mm above the highest part of a sink, basin or bath. Infinity REU-2425W - 6 - Issue 2 - 5/07/04 ©Rinnai...
Page 10 Limiting Device. Installations without a Temperature Limiting Device are shown in Diagram 1. If you are unsure about your local regulations contact your regulating authority or Rinnai. If the appliance does not have this label, or your local regulations require installation with a Temperature Limiting Device then install the appliance in accordance with Diagram 2.
Page 11 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. Infinity REU-2425W - 8 - Issue 2 - 5/07/04 ©Rinnai...
Page 12: Safety Devices
If the outgoing water temperature reaches 3°C above the preset temperature, the burner will automatically go out. The burner will only ignite again once the outgoing hot water temperature falls below the preset temperature. Infinity REU-2425W - 9 - Issue 2 - 5/07/04 ©Rinnai...
Page 13: Specification
Combustion fan rpm check- Integrated circuit system Over current- Glass fuse (5 Amp). Remote control MC-91-1A- Universal control MC-70-2A- Kitchen control BC-70-2A- Bathroom control Remote control cable Non polarised two-core cable Infinity REU-2425W - 10 - Issue 2 - 5/07/04 ©Rinnai...
Page 16: Combustion Specification
Pressure 0.90 0.08 Propane/LPG # 2.26 (1.90) 0.17 (0.15) Burner type Propane Common Dip Switch positions Refer to page 14 Note: LPG values specified in brackets are for New Zealand. Infinity REU-2425W - 13 - Issue 2 - 5/07/04 ©Rinnai...
Page 17: Dip Switch Positions
43°C, 50°C, 55°C, 60°C, 65°C, or 75°C available. 1. Gas Type Only alter gas type positions when converting. For conversion instructions refer to page 43. 2. Maximum Water Flow Select Infinity REU-2425W - 14 - Issue 2 - 5/07/04 ©Rinnai...
Page 18 The black squares indicate the position of switches. b) It will be noted that some dip switch configurations are the same for a given temperature whether controllers are connected or not. These similarities are not mistakes. Infinity REU-2425W - 15 - Issue 2 - 5/07/04 ©Rinnai...
Page 19: Water Flows
36000 = 45 x 60 x Q TE = 80% 36000 Q = Water flow in Litres per minute = 60 x Q -------------- - 800 = 60 x Q -------- - 13.3 L/min Infinity REU-2425W - 16 - Issue 2 - 5/07/04 ©Rinnai...
Page 20 Incoming Incoming temp. +15°C +25°C +30°C +35°C +45°C +50°C Output water with mixing with mixing with mixing 17.1 L/min 13.3 L/min 11.9 L/ vol. 40 L/min 24 L/min 18 L/min Infinity REU-2425W - 17 - Issue 2 - 5/07/04 ©Rinnai...
Page 21: Main Components
12. Main Components 1. Mechanical Water Regulator Rinnai’s unique water regulator mechanism ensures the hot water is maintained with no noticeable change to the desired temperature during use, even if water pressure drops due to another tap being turned on and increasing the demand.
Page 22 The water flow control consists of a plug and barrel valve which is rotated by a motor to increase or decrease the volume of water passing through the heat exchanger. Water flow control device. Infinity REU-2425W - 19 - Issue 2 - 5/07/04 ©Rinnai...
Page 23: Time Charts
13. Time Charts Normal Combustion Sequence Error Sequence (Ignition / Flame Failure) Pre-purge Defect Sequence Infinity REU-2425W - 20 - Issue 2 - 21/03/05 ©Rinnai...
Page 24: Operation Flow Principle
Change-over sld SV2 Closed Main gas sld SV1 Closed Modulating valve Open Main gas sld SV1 Closed Sparker Sparker ( after 4 seconds ) Only applicable when remote control is connected Infinity REU-2425W - 21 - Issue 2 - 5/07/04 ©Rinnai...
Page 25 Hot water tap Water flow sensor Combustion indicator Main gas sld SV1 Closed Change-over sld SV2 Closed Change-over sld SV3 Closed Modulating valve Post fan stops (65 sec) ON/OFF switch Indicators Infinity REU-2425W - 22- Issue 2 - 24/06/04 ©Rinnai...
Page 26: Operation Principles
[See section on “Main Components” on page 18, for clarification]. Infinity REU-2425W - 23 - Issue 2 - 5/07/04 ©Rinnai...
Page 27 The PCB stores data on the calculated incoming water temperature, ready for when the hot water is turned on again. The data is used to calculate the initial gas flow. Infinity REU-2425W - 24 - Issue 2 - 5/07/04 ©Rinnai...
Page 28: Fault Finding
(page 31) operational faults and readout of electrical values whilst unit operational. (page 27) Dismantling for Service Detailed information on how to remove and replace components. (page 45) Infinity REU-2425W - 25 - Issue 2 - 5/07/04 ©Rinnai...
Page 29: Fault Finding Table
2. Check heat exchanger outlet thermistor. 3. Check gas valves 4. Check water flow servo. Anti-frost heater does not operate. 1. Check anti-frost heater components. 2. Check frost sensing switch. Infinity REU-2425W - 26 - Issue 2 - 18/08/04 ©Rinnai...
Page 30: Maintenance Monitor / Error History
*Note 2 Remote Control Connections Bathroom Remote Controls connected Display Additional remote Kitchen remote “0” “ 0 1 ” “1” Water flow servo present recognising positioning None 0~2 *Note 3 Infinity REU-2425W - 27 - Issue 2 - 5/07/04 ©Rinnai...
Page 31 Clock display. To return to normal operation • Press the ON/OFF button again while holding the Water Temperature “UP” (Hotter) button. • This feature will automatically shut down after 3 minutes. Infinity REU-2425W - 28 - Issue 2 - 5/07/04 ©Rinnai...
Page 32: Component Circuit Value Table
- red AC 90~110 V green - green AC 16~20 V orange - orange AC 13~30 V brown - grey AC 30~50 V yellow - grey AC 180~220 V Infinity REU-2425W - 29 - Issue 2 - 5/07/04 ©Rinnai...
Page 34: Fault Diagnosis
AC 30 ~ 50V / 6 ~10 yellow - grey Ω AC 180 ~ 220V / 0.4 ~ 0.6 If normal, check 3 at top of next page. Faulty: Replace the transformer. Infinity REU-2425W - 31 - Issue 2 - 5/07/04 ©Rinnai...
Page 35 Faulty: Replace water flow control. Measure the voltage between yellow and black of the relay connector (a Normal: DC 2 ~ 10V If normal, go to 2). Faulty: Replace the water flow sensor. Infinity REU-2425W - 32 - Issue 2 - 5/07/04 ©Rinnai...
Page 36 Ω Resistance > 1M = open circuit. Ω Resistance < below 1 = short circuit. Normal: proceed to check item 4) on next page. Faulty: replace the water temperature thermistor. Infinity REU-2425W - 33 - Issue 2 - 5/07/04 ©Rinnai...
Page 37 Faulty: Replace the PCB unit # Disconnect I , and measure the resistance between sparker terminals Normal: >1M Ω If there is no spark, adjust or replace the electrode. Faulty: Replace the sparker. Infinity REU-2425W - 34 - Issue 2 - 5/07/04 ©Rinnai...
Page 38 (SV Measure the voltage at changeover solenoid valve (SV ) blue ~ black connector. Normal: DC 80 ~ 100V If normal, check item 9). Faulty: Replace the PCB unit. Infinity REU-2425W - 35 - Issue 2 - 5/07/04 ©Rinnai...
Page 39 If normal, check for any other causes for flame failure (eg. gas valve is open, blocked filter, etc) Faulty: Secure the earth. Infinity REU-2425W - 36 - Issue 2 - 5/07/04 ©Rinnai...
Page 40 Measure the voltage at the changeover solenoid (SV3) blue ~ black connector. Normal: DC 80 ~ 100V If normal, go to item 3) on the next page. Faulty: Replace the PCB unit. Infinity REU-2425W - 37 - Issue 2 - 5/07/04 ©Rinnai...
Page 41 Normal: Less than DC 0.5 V Faulty: Change water flow servo with sensor. Infinity REU-2425W - 38 - Issue 2 - 5/07/04 ©Rinnai...
Page 42 (AC100V circuit) Faulty: Replace the frost sensing switch. * Where the low room temperature cannot be achieved, please cool with ° iced water or cold water below 4 C. Infinity REU-2425W - 39 - Issue 2 - 5/07/04 ©Rinnai...
Page 43: Electrical Component Analysis
Ω Error code “72” dis- 2. Check flame rod. * Measure resistance between Replace PCB. Resistance > 1M played on digital moni- flame rod terminal A Replace flame rod. earth. Infinity REU-2425W - 40 - Issue 2 - 5/07/04 ©Rinnai...
Page 44 2. Check earth lead. Check for faulty earth connec- Are connections OK? Yes Check other causes for tions (to round terminals) for flame failure. broken wires or short circuits Adjust/replace earth lead. Infinity REU-2425W - 41 - Issue 2 - 5/07/04 ©Rinnai...
Page 45 2. Check frost sensing Disconnect connector f Check wiring. Is resistance < 1 switch. measure the resistance Replace frost sensing between blue-blue. Atmos- switch. pheric temperature less than ± ° Infinity REU-2425W - 42 - Issue 2 - 5/07/04 ©Rinnai...
Page 46: Gas Conversion
16.Follow gas pressure setting procedure, (see next page). 17.Check for gas escapes with soapy water. 18.Disconnect appliance from services (if in workshop). 19.Replace front cover, star washer must be on bottom right hand screw. Infinity REU-2425W - 43 - Issue 2 - 5/07/04 ©Rinnai...
Page 47: Gas Pressure Setting Procedure
LPG (NZ) 1.90 kPa Position switch No.2 and No.3 of the bottom set of dip switches to the “OFF” position. Turn water OFF. Replace plug in base. Replace protective plastic cover over PCB. Infinity REU-2425W - 44 - Issue 2 - 5/07/04 ©Rinnai...
Page 48: Dismantling For Service
8. Removal of Manifold and Burner ..............48 9. Removal of Gas Control ................49 10.Removal of Heat Exchanger ..............49 11.Removal of Thermal Fuse................50 Unless otherwise stated, reassembly is the reverse of dismantling Infinity REU-2425W - 45 - Issue 2 - 5/07/04 ©Rinnai...
Page 49: Removal Of Front Panel
- Isolate Water Supply. Remove one (1) screw from the heat exchanger water supply pipe to release the metal lock. Pull the pipe towards yourself to release. Handle O-ring carefully. (phillips driver) Infinity REU-2425W - 46 - Issue 2 - 5/07/04 ©Rinnai...
Page 50: Removal Of Sparker
- Isolate Water Supply. a. Remove the two (2) screws that secure the thermistor in place to remove the water temperature thermistor. (phillips driver). Infinity REU-2425W - 47 - Issue 2 - 5/07/04 ©Rinnai...
Page 51: Removal Of Transformer
(phillips driver) Disconnect connectors. Remove the five (5) screws that secure the manifold in place and pull out the manifold (phillips driver). Pull burner unit forward to remove (hand) Infinity REU-2425W - 48 - Issue 2 - 5/07/04 ©Rinnai...
Page 52: Removal Of Gas Control
Remove the three (3) screws securing the manifold to the gas control. Remove four (4) screws that secure the heat exchanger unit in place. Infinity REU-2425W - 49 - Issue 2 - 5/07/04 ©Rinnai...
Page 53: Removal Of Thermal Fuse
13) Removal of Thermal Fuse CAUTION - 240 volt potential exposure. Isolate the appliance and reconfirm with a neon screwdriver or multimeter. Remove the heat exchanger unit; refer to section 10. Infinity REU-2425W - 50 - Issue 2 - 5/07/04 ©Rinnai...
Page 58: Parts List
HARNESS - Wire, Fan Motor BU195-602 290-227-000 HARNESS - Wire, Sensor BU195-603 290-011-000 92081777 HARNESS - Wire, Water Flow Servo BU195-604 290-225-000 92081785 HARNESS - Wire, Flame Rod AU195-605 290-748-000 Infinity REU-2425W - 46 - Issue 2 - 20/07/05 ©Rinnai...
Page 59 92081926 MANIFOLD O-Ring Gas C36F8-1 580-202-000 92075126 O-RING M10B-2-4 520-209-010 O-RING M10B-2-7 520-281-010 92043231 O-RING M10B-2-12 520-213-010 92063551 O-RING M10B-2-12.5 520-255-010 92071422 O-RING M10B-2-14 520-193-010 92062207 O-RING M10B-2-18 520-049-010 92071182 Infinity REU-2425W - 47 - Issue 2 - 20/07/05 ©Rinnai...
Page 61 NEW ZEALAND LTD. Internet: www.rinnai.co.nz E-mail: sales@rinnai.co.nz Head Office, New Zealand 691 Mt. Albert Road, Royal Oak, Auckland P O Box 24-068 Tel: (09) 625 4285 Fax: (09) 624 3018 24 hr Service Tel: 0800 746624 (0800 Rinnai) REU-2425W SM 01/2002...

This manual is also suitable for:

Reu-2020w Reu-2422w Reu-2425wInfinity reu-2425w

Rinnai REU-2018W Service Manual

Table of Contents

25. Dismantling for Service

Quick Links

Chapters

Need help?

Questions and answers

Related Manuals for Rinnai REU-2018W

Summary of Contents for Rinnai REU-2018W

This manual is also suitable for:

Table of Contents