Rheem 834 Series Operating instructions

This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
R
Rh he ee em m A Au us st tr ra al li ia a P Pt ty y L Lt td d A AB BN N 2 21 1 0 09 98 8 8 82 23 3 5 51 11 1
SERVICE INSTRUCTIONS
834 Series Hydroelectric
Instantaneous Gas Water Heaters
TM081
Revision: AA
Issued: Feb 2017
Issued: October 2016
834012N0
834012P0
834016N0
834016P0

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
2
CONTENTS
INTRODUCTION .................................................................................................................3
SAFETY WARNINGS..........................................................................................................3
MODEL IDENTIFICATION...................................................................................................4
SPECIFICATIONS...............................................................................................................4
PREVENTATIVE MAINTENANCE ......................................................................................6
Frost Protection & Draining the Water Heater..................................................................7
INSTALLATION...................................................................................................................7
WIRING DIAGRAM –ALL MODELS ...................................................................................8
PLUMBING DIAGRAMS......................................................................................................9
OPERATION......................................................................................................................10
Sequence of Operation ..................................................................................................10
Sequence of Operation Component Diagram.............................................................13
Operational Flow Chart –All Models..............................................................................14
To Turn the Heater ON –Lighting Instructions...............................................................15
To Turn the Heater OFF.................................................................................................15
COMPONENTS AND THEIR FUNCTION .........................................................................16
Gas Valve.......................................................................................................................18
Temperature Controller..................................................................................................18
Ignition Module...............................................................................................................19
PRODUCT CHANGES ......................................................................................................19
FAULT FINDING................................................................................................................20
Common Complaints......................................................................................................20
Operational & Fault Indication........................................................................................21
Fault Finding Charts.......................................................................................................22
Fault Diagnosis Sequence (General Fault Finding Chart) ..........................................22
Fault Finding Tests.........................................................................................................39
COMPONENT ADJUSTMENT PROCEDURES & CHECKS.............................................45
Adjusting the Seasonal Adjustment Valve......................................................................45
Adjusting the Setpoint Temperature...............................................................................45
DIP Switch Adjustments.................................................................................................45
Resetting the Overheat Switch.......................................................................................46
Adjusting the Ignition Rod Gap.......................................................................................46
Adjusting the Flame Sensor ...........................................................................................46
Checking Inlet Gas Pressure..........................................................................................47
Checking & Adjusting Burner Gas Pressure...................................................................47
Adjusting the Gas Valve Gas Regulator.........................................................................49
COMPONENT REPLACEMENT PROCEDURES .............................................................50
DOCUMENT REVISION HISTORY...................................................................................61

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
3
INTRODUCTION
The information provided in these Service Instructions is based on the water heater being
installed in accordance with AS/NZS 5601.1 and the Installation Instructions provided with
each water heater.
Should you require further technical advice on a Rheem 834 Series Hydroelectric
Instantaneous Gas Water Heater, contact your nearest Rheem Service department where
genuine replacement parts are also available.
SAFETY WARNINGS
The purpose of this service manual is to provide sufficient information to allow a person
with the skills as required by the Regulatory Authorities to carry out effective repairs to a
834 Series Hydroelectric Instantaneous Gas Water Heater in an efficient manner.
Safety precautions or areas where extra care should be observed when conducting tests
outlined in this service manual are indicated in bold italics and/or a warning symbol.
Recommended procedures must be observed.
'Live' testing to be conducted. Control circuit components may have up to
3.7 VDC present.
Isolate water supply to heater to prevent heater from operating before
conducting the indicated test.
Hot surface or liquid. Personal Protective Clothing (PPE) shall be worn to
reduce the risk of scalding.
General warning symbol. Observe instructions accompanying symbol.
Heater Warnings
Do not modify this appliance. When conducting repairs, the gas train
including injector sizes must not be altered in any way.

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
4
MODEL IDENTIFICATION
The identification numbers are designed to convey detailed information about the water
heater to which it is attached. Model number, serial number and date of manufacture must
be quoted in all correspondence.
8
3
4
012
N
0
Model Number
8 - Rheem
Location
3 –Outdoor
Ignition Type
4 –Internal Battery
Capacity
Nominal litres/minute @ 25 ºC rise
Gas Type
N - Natural
P - Propane
0 –No frost protection
SPECIFICATIONS
Heater Specifications
Specification
834012N0
834012P0
834016N0
834016P0
Gas Consumption
Minimum (MJ/hr)
31.2
31.3
41.5
43
Maximum (MJ/hr)
99
96
128
125
Electrical
Supply
3.7 VDC battery & integral hydro electric generator
Gas Supply
Connection
R 3/4" BSP Female
Min Gas Pressure
1.13 kPa
2.75 kPa
1.13 kPa
2.75 kPa
Max Gas Pressure
3.5 kPa
3.5 kPa
3.5 kPa
3.5 kPa
Water Connections
Inlet
R 1/2" BSP Male
Outlet
R 1/2" BSP Male
Water Pressure (1)
Minimum
150 kPa
Maximum
800 kPa
Minimum Starting Flow Rate / Pressure
3.04 L/min / 64 kPa
Pressure Relief Valve Setting
850 kPa
Temperature Setting (2)
45°C, 50°C or 60°C selectable (factory set @ 60°C)
Burner Gas
Pressure settings
Min Setting (kPa)
0.080
0.21
0.088
0.21
Max Setting (kPa)
0.72
1.85
0.74
1.85
IP Rating (3)
N/A
N/A
N/A
N/A
(1) If the water supply pressure exceeds 80% of the maximum water supply pressure, a pressure limiting
valve must be installed.
(2) Selectable via temperature controller DIP switches 7 & 8. To be performed by suitably qualified persons
only (refer to 'Adjusting the Setpoint Temperature' on page 45).
(3) Not applicable due to not being connected to an electrical power supply.

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
5
Component Specifications
Resistance value tolerances ±10%.
Specification
834012N0
834012P0
834016N0
834016P0
Water Flow Sensor
Pulses voltage supplied from temperature control
according to water flow rate
21 Hz @ 3.01 L/m, 74 Hz @ full flow rate
Hydro Electric Generator (G)
Generates 1.1 ~ 1.7 VDC
(8 ohms: white wire to white wire)
Water Throttle Valve (WV)
Start voltage ≥ 2.4 VDC, hold in > 0.32 VDC
(8 ohms: white wire to white wire)
Gas
Valve
SV1 (pilot valve)
Ignition voltage > 0.9 VDC, hold in > 0.1 VDC
(40 ohms: orange wire to earth)
SV2 (main burner safety valve)
> 0.9 VDC (60 ohms: green wire to earth)
SV3 / MASV (4)
SV3
> 0.6 VDC (100 ohms: green wire to earth)
MASV
> 1.2 VDC (8 ohms: red wire to black wire)
Yellow wire output motor operation pulse check
Hot Water Outlet Temperature Sensor
For temp/resistance chart refer to ‘Testing the Hot
Water Outlet Temperature Sensor’ on page 39
Overheat Protection
Software
Hot water outlet temperature shut down @ 85°C
Overheat Switch
Contacts open @ 95°C ± 4.5°C
manual reset @ ≤ 90°C
Ignition Module
Model
P700 (refer to 'Ignition Module' on page 19)
Flame Sensitivity
> 0.5 µA. Normal flame generation 2 ~ 10 µA
(2 µA @ min fire, 10 µA @ max fire)
Temperature
Controller
Model
AT102-RH
Battery
3.7 VDC lithium ion rechargeable 600 mA/h
DIP Switches
Refer to 'DIP Switch Adjustments' on page 45
Min & Max Dials
Refer to 'Checking & Adjusting Burner Gas
Pressure' on page 47
Ignition Rod
3.5 ~ 4mm gap. Refer to 'Adjusting the Ignition Rod
Gap' on page 46
Flame Sensor
Refer to 'Adjusting the Flame Sensor' on page 46
Burner Injectors
Quantity
14
14
18
18
Orifice diameter
1.3 mm
0.8 mm
1.3 mm
0.8 mm
Inlet Water Strainer
Accessed by removing cold water inlet drain plug
(4) SV3 / MASV = Motor Adjustable Solenoid Valve (gas flow rate control) for main burner.

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
6
PREVENTATIVE MAINTENANCE
Minor maintenance should be performed every six months by the dwelling occupant and a
major service should be performed every five years by a suitably qualified person.
Note: The water heater is not fitted with frost protection and must be drained if freezing
conditions are likely to occur (refer to 'Frost Protection & Draining the Water Heater' on
page 7).
Only genuine replacement parts should be used on this water heater.
Minor Six Month Maintenance
1. Inspect around the air inlet / flue terminal and the water heater in general for plant
growth and trim back any shrubs or bushes that have encroached around the water
heater.
2. Inspect around the water heater for insect infestations such as ants. Spray insecticide
around the water heater if necessary to rid the area of insects. Do not spray the water
heater surface or into the air inlet / flue terminal of the water heater.
Do not spray around the water heater with insecticide while the water
heater is operating. Propellants in insect spray may contain hydrocarbon
which can catch fire. Close the cold water isolation valve to the water
heater to prevent the water heater from operating while you spray around
the water heater. Open the cold water isolation valve when finished.
3. If required, clean the water heater with a soft cloth and warm mild soapy water. Under
no circumstances should abrasive materials, powders or chemicals be used.
4. Check to ensure the drain line from the safe tray (if one is installed) is not blocked.
5. Check heater operation.
6. Warn customer of the danger of storing chemicals and/or using flammable materials or
aerosol spray packs near the heater. Aerosols and harsh chemicals can also cause
premature failure of heater components.
Major Five Year Service
Servicing must be performed by a suitably qualified person.
1. Conduct the Minor Six Month Maintenance procedure detailed above PLUS;
2. Remove and clean cold water inlet strainer (refer to component replacement
procedure 15 on page 55).
3. Remove and clean burner (refer to component replacement procedure 10 on page 53).
4. Check and if necessary adjust the burner gas pressure (refer to 'Checking & Adjusting
the Burner Gas Pressure' on page 47).
5. Inspect all plumbing connections and components for leaks.
6. Inspect all electrical connections.
7. Visually inspect the water heater for any potential problems.
DO NOT return the heater to service if any test/check result is outside
specifications or if an unsafe condition exists.

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
7
Frost Protection & Draining the Water Heater
The water heater is not fitted with frost protection and must be drained if freezing
conditions are likely to occur.
To Drain the Water Heater
1. Close the gas isolation valve at the inlet to the water heater.
2. Close the cold water isolation valve at the inlet to the water heater.
3. Open a hot tap (preferably a shower outlet).
4. Unscrew the drain plug on the cold water inlet.
5. Unscrew the drain plug / pressure relief valve (PRV) on the hot water outlet. Water will
now drain from the heater.
6. Close the hot tap when water stops flowing from the water heater.
Note: Do not replace the drain plugs until the water heater is to be turned back on again.
To reinstate the heater after draining refer to 'To Turn The Heater ON –Lighting
Instructions' on page 15.
The hot water outlet drain plug is also the heater's PRV. Do not use any
other type of fitting to replace the drain plug / PRV.
INSTALLATION
All models must be installed in accordance with AS/NZS 5601.1, all local codes and
regulatory authority requirements and the Installation Instructions supplied with the heater.
The following should also be noted:
The water heater is suitable for outdoor installations only.
The water heater is not suitable for pool heating.
The water heater is not suitable for in-series solar boosting.
The water heater is not suitable for hot water reticulation systems.
If the water heater is mounted on a wall constructed of combustible material, the wall
must be protected by a fire resistant heat shield.
A minimum water supply pressure of 140 kPa is required to achieve the rated flow and
performance of the water heater.
The inlet water temperature must not exceed 35°C.
For more information refer to the Installation Instructions supplied with the heater.

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
8
WIRING DIAGRAM –ALL MODELS

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
9
PLUMBING DIAGRAMS
A disconnection union MUST always be provided at the water inlet and water outlet
connections and the gas inlet connection to allow for disconnection of the water heater.
An isolation valve MUST always be provided at the water inlet and gas inlet to allow for
servicing and disconnection of the water heater.
A temperature limiting device must be fitted between an 834 Series
Hydroelectric Instantaneous Gas Water Heater and the hot water outlets in
any ablution and public areas such as a bathroom, ensuite or public
amenities, to reduce the risk of scalding regardless of the water heaters
setpoint temperature.
The temperature limiting device must have a specified ‘minimum temperature
differential’ between the hot water inlet and the tempered water outlet of no greater
than 10°C, and a specified ‘maximum permitted pressure variation’ in the supply
between the hot water inlet and the cold water inlet of no less than 15%.
Where a temperature limiting device is installed adjacent to the water heater, the cold
water line to the temperature limiting device can be branched off the cold water line
either before or after the isolation valve and pressure limiting valve to the water heater.
If a pressure limiting valve is installed on the cold water line to the water heater and
the cold water line to a temperature limiting device branches off before this valve or
from another cold water line in the premises, then a pressure limiting valve of an equal
pressure setting may be required prior to the temperature limiting device.
Two Temperature Zones Using a Temperature Limiting Device

TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
10
OPERATION
Overview
The heater consists of a gas burner and a copper heat exchanger. When a hot tap is
opened, cold water enters the heater, flows through the heat exchanger and is delivered to
the hot water outlet. Hot flue gases from the burner pass between the fins on the heat
exchanger tube where heat is transferred to the fins and then by conduction into the water
flowing through the fin tube of the heat exchanger. Combustion gasses from the burner
exit via the flue terminal by natural draught where they are dispelled to atmosphere. The
gas supply to the burner from the gas valve is controlled by a temperature controller which
senses the hot water outlet temperature via a temperature sensor and adjusts the gas rate
to the main burner to achieve the desired hot water outlet temperature.
The water heater is activated and deactivated by water flow and a rechargeable 3.7 VDC
battery is utilised to power the water throttle valve and reset the MASV to low fire position
during shut down when there is no water flow through the heater. When water is flowing
through the heater, extra low voltage (1.1 ~ 1.7 VDC) is generated by a hydro electric
generator which is utilised to power the control circuit and recharge the battery.
834 Series Hydroelectric Instantaneous Gas Water Heaters have an interrupted pilot i.e.
the pilot is lit during the ignition period and is extinguished during normal operation of the
main burner.
The following 'Sequence of Operation' and 'Operational Flow Chart' sections detail heater
operation.
Sequence of Operation
Refer to ‘Sequence of Operation Component Diagram’ on page 13 to view components
shown in brackets, e.g. (1) if identification is required.
Note: Fault indication referred to throughout this section is indicated by the temperature
controller LED's. For more details refer to 'Operational & Fault Indication' on page 21.
1. When a hot tap is opened, the resulting water flow through the heater causes the
hydro electric generator (1) to generate an extra low voltage (1.1 ~ 1.7 VDC). The
water flow sensor (2) detects the water flow and sends a pulse signal to the
temperature controller (3) that is proportionate to the water flow rate through the
heater. Operation past this point will not occur unless the water flow rate is > 3 L/m.
2. If water flow rate through the heater is > 3 L/m, as determined by the water flow sensor
(2) pulse rate, the temperature controller (3) initialises, illuminates it's green LED and
drives the MASV (Motor Actuated Solenoid Valve) (4) to the minimum opened
(minimum gas rate) position. Note: No gas is let through to the main burner (5) as the
main gas train solenoid valves SV2 (6) and SV3 (7) are not yet energised.
3. The ignition module (8) is energised and performs a check for false flame via the flame
sensor (9). If a false flame is detected (> 0.5 µA for ≥ 3 seconds), fault indication is
provided and the heater will not operate until it has been reset (hot tap turned off and
then turned back on) at which time the heater will restart from step 1. Operation past
this point assumes a false flame has not been detected.
4. The ignition module (8) supplies high voltage pulses to the ignition rod (10)which arcs
(sparks) across the gap between the ignition rod and the pilot (11) hood. SV1 (12) is
energised which allows gas to travel to the pilot which is ignited by the ignition rod
spark.