Rheem RTGH-RH10DV User manual

Service Manual
WARNING
–Donotstoreorusegasolineorother󰘱ammablevaporsandliquidsinthevicinityofthisoranyother
appliance.
– WHAT TO DO IF YOU SMELL GAS
 ·Donottrytolightanyappliance.
 ·Donottouchanyelectricalswitch;donotuseanyphoneinyourbuilding.
 ·Immediatelycallyourgassupplierfromaneighbor’sphone.Followthegassupplier’sinstructions.
 ·Ifyoucannotreachyourgassupplier,callthe󰘰redepartment.
–Installationandservicemustbeperformedbyaquali󰘰edinstaller,serviceagencyorthegassupplier.
Iftheinformationintheseinstructionsisnotfollowedexactly,a󰘰reorexplosionmayresult,
causingpropertydamage,personalinjury,ordeath.
Models
CONDENSING TANKLESS GAS WATER HEATER
199,000Btu / 180,000Btu
• Natural Gas(NG) / Liquid Propane Gas (LP)

2
Chapter1ProductCharacteristics Speci󰘰cations 6
Dimensions 7
NamesofComponents 8
Hot Water Supply Capability 9
Pressure Loss Characteristics 10
Operating Principle 11
TimingLogic 13
OperationFlowChart 14
FreezeProtectFlowChart 15
WiringDiagram 16
Chapter2 ComponentsDescription CircuitBoard 21
TemperatureThermistors 22
OverheatLimitSwitch 23
WaterLeakageDetector 24
GasLeakDetectorSensor 25
AirPressureSwitch 26
FlowControlValve 27
FlowSensor 28
Igniter 29
FlameDetectionSensor 30
AGM 31
GasValve 32
Fan 33
MetalFiberPremixBurner 34
WaterMixingValve 35
CirculationPump 36
DHW Inlet Filter 37
HeatExchanger 38
CondensateTrap 39
Chapter3HowtoUseTheControlPanel ControlPanelInterface 40
ControlPanelDisplay 41

3
Changing the DHW Set Point 41
StatusDisplayMode 42
ChangingTheTime 43
InstallerMode 44
RecirculationMode 45
SettheRecirculationTimerType 47
SettingtheRecirculationRunTime 48
ResettingTheRecirculationRunTime 49
Chapter4Troubleshooting ErrorCodeList 55
Error10 56
Error11 57
Error16 57
Error20 58
Error 29 59
Error31 60
Error32 61
Error33 62
Error35 63
Error39 64
Error40 65
Error41 66
Error43 67
Error45 68
Error60 69
Error61 70
Error65 71

4
Error 66 72
Error 67 73
Error 72 74
Error73 75
Error 76 76
Error 78 77
Error94 78
Chapter5 ReplacementInstructions 1.CircuitBoard 79
2.Igniter 80
3.FlameDetectionSensor 81
4.GasLeakDetector 81
5.AirPressureSwitch 82
6.GasValve 83
7.FlowControlValve 84
8.WaterMixingValve 85
9.CirculationPump 86
10.AGM 87
11.FanAssembly 88
12.HeatExchanger 89
Chapter6 Maintenance 1.CleaningtheWaterHeater 92
2.MaintenanceProcedures 93
3.FlushingtheWaterHeater 95
Chapter7 ComponentsDiagram Part I _ Case Part 96
Memo 97

6Chapter1ProductCharacteristics
Specications
Model Name
RTGH-RH11DV RTGH-RH10DV
Gas Input Rate
MAX 199,000 Btu/h 180,000 Btu/h
MIN 18,000 Btu/h 18,000 Btu/h
High Altitude
(2,500~4,500ft) 180,000 Btu/h 180,000 Btu/h
Hot Water Capacity
35°F Rise 11.0 Gal 9.9 Gal
45°F Rise 8.5 Gal 7.7 Gal
77°F Rise 5.0 Gal 4.5 Gal
Installation Indoor Wall Hung
Flue System Sealed Combustion Direct Vent, Single Vent
Max Vent Run 2″(50ft) / 3″(100ft) Schedule 40 PVC, CPVC, PP
Orice Size NG (Gas / Needle) 0.342″(8.7mm) / 0.354″(9.0mm)
LP (Gas / Needle) 0.263″(6.7mm) / 0.267″(6.8mm)
Gas Supply Pressure NG 5.0″ W.C to 10.5″ W.C
LP 9.5″ W.C to 13.0″ W.C
Manifold Pressure
Gas Type NG LP NG LP
Low Fire 2″ VENT -0.07" W.C -0.02" W.C -0.07" W.C -0.02" W.C
3″ VENT -0.07" W.C -0.02" W.C -0.07" W.C -0.02" W.C
High Fire 2″ VENT -0.38" W.C -0.3" W.C -0.36" W.C -0.28" W.C
3″ VENT -0.33" W.C -0.25" W.C -0.31" W.C -0.23" W.C
Power Supply
Main Supply 120V 60Hz
Maximum
Power Consumption 172W(82W+90W_PUMP)
Ignition System Direct Electronic Ignition / Automatic Flame Sensing
Burner System Premixed Metal Fiber Burner
Gas Valve System Air ratio valve
Minimum Flow Activation Flow 0.5 GPM
Internal Pipe Material STS 304, Copper Tubing
Dimensions W17.3″ – H28.7″ – D14.8″
Weight 85 lbs
Water Holding Capacity Under 2 Gallon
Control Panel / Main Controller P-950C / NGTH-9700C
Water Pressure MAX Hot water 150 psi
MIN 15 psi
Materials Casing Cold Rolled Carbon Steel
Heat Exchanger Heat Exchanger : STS 304
Safety Devices
Flame Sensor, Overheat Cut Off Limit Switch ,
Gas Leak Detector sensor, Water Leak Detector Sensor
Exhaust Temperature Sensor,
Water Temperature Sensor

7
Chapter1ProductCharacteristics
Dimensions
DESCRIPTION DIAMETER
A Exhaust Outlet Pipe 3” (7.6 cm)
B Air Intake 3” (7.6 cm)
CDHW Outlet Adapter ¾” (1.9 cm)
DCondensate Adapter ½” (1.2 cm)
E Recirculation Return ¾” (1.9 cm)
FDHW Inlet Adapter ¾” (1.9 cm)
G Gas Inlet ¾” (1.9 cm)
6.1" [156mm] 5.4" [136mm]
2.4" [60mm]
6.8" [173mm]
2.6" [67mm]
3.2" [81mm]
10.2" [260mm]
13.6" [346mm]
4.0" [101mm]
11.5" [292mm]
4.6" [117mm]
28.7" [728mm]

8
NameofComponents
Chapter1ProductCharacteristics
30
NO Name of Component
1
Exhaust Outlet Collar
2
Ignition Trans
3
Ignition Rod
4
Over-heating Switch
5
Primary Heat Exchanger
6
H/E Temperature Sensor
7
Secondary Heat Exchanger
8
Control Panel
9
Mixing Valve
10
Recirculation Pump
11
'DHW' supply Adapter
12
Condensate Trap
13
Low level sensor
14
Recirculation Return Adapter
15
Main Controller
16
‘DHW’ Inlet Filter
NO Name of Component
17
‘DHW’ Inlet Adapter
18
Gas Inlet Adapter
19
Manual Power Switch
20
Water Flow Control Valve
21
Air Pressure Switch
22
Flame Detection Sensor
23
Gas Valve
24
Burner Case
25
AGM(Air Gas Mixer)
26
BLDC Fan
27
Air Intake Filter
28
Air Intake Collar
29
Exhaust Thermistor
30
Heat Exchanger Thermistor
31
Cold Water Thermistor
32
Flow Sensor
3
5
2
1
4
6
7
8
9
29
3132
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

9
HotWaterSupplyCapability
199,000Btu/hr 180,000Btu/hr
80
90
100
110
120
130
140
150
160
0123456789
Set Tempeature [℉]
Flow Rate[GPM]
[Winter]inlet water temp 48℉
80
90
100
110
120
130
140
150
160
012345678910 11 12
Set Tempeature [℉]
Flow Rate[GPM]
[Spring/Fall]inlet water temp 64℉
80
90
100
110
120
130
140
150
160
0246810 12
Set Tempeature [℉]
Flow Rate[GPM]
[Summer]inlet water temp 82℉
80
90
100
110
120
130
140
150
160
0123456789
Set Tempeature [℉]
Flow Rate[GPM]
[Winter]inlet water temp 48℉
80
90
100
110
120
130
140
150
160
0 1 2 3 4 5 6 7 8 9 10
Set Tempeature [℉]
Flow Rate[GPM]
[Spring/Fall]inlet water temp 64℉
80
90
100
110
120
130
140
150
160
0246810 12
Set Tempeature [℉]
Flow Rate[GPM]
[Summer]inlet water temp 82℉
Chapter1ProductCharacteristics

10
0
2
4
6
8
10
12
14
16
18
012345678910 11 12 13
Headpressure [ft]
Flow rate [GPM]
<CIRCULATION PUMP>
Pressure Loss Characteristics
Chapter1ProductCharacteristics

11
Chapter1ProductCharacteristics
OperatingPrinciple(Standard/ExternalMode)
1. Only POTABLE water may be plumbed through
the water heater.
2. The water heater cannot be used for space
heating applications.
3. Expansion tank is required if a backflow
preventer is installed.
4. Isolation valve kits are recommended for this
installation.
Standard Mode
Air & Gas
Mixing
Recirculation
Pump
Hot Water Oulet
Condensate Hose
Burner
Secondary heat
exchanger
Primary heat
exchanger
Cold Water Inlet
Gas
Pressure Relief Valve
Expansion Tank (Install
according to local code)
Backow Preventer
(optional)
When using external recirculation mode with
the built-in pump, check the following maximum
recirculation pipe lengths including fittings (3/4"
pipe is recommended):
-1/2" Pipe- 200' (60m) of equivalent length
-3/4" Pipe- 500' (150m) of equivalent length
Lengths in excess of these limits will require an
external recirculation pump.
Cold Water Inlet
Expansion Tank (Install
according to local code)
Air & Gas
Mixing
Primary heat
exchanger
Secondary heat
exchanger
Burner
Hot Water Outlet
Pressure Relief Valve
Recirculation
Pump
Recirculation Line
Condensate Hose
Gas
External Recirculation mode
The recirculation pipe must be installed in the eld in
order to use ‘External Recirculation Mode’.
This mode allows the water heater to recirculate
heated water through the system and additionally
serves as a freeze protection function.
Expansion Tank (Install
according to local code)
Recirculation
Pump
Pressure Relief Valve
Hot Water Oulet
Condensate Hose
Cold Water Inlet
Gas
Air & Gas
Mixing
Primary heat
exchanger
Burner
Secondary heat
exchanger

12
OperatingPrinciple(PreheatorInternalMode/bYPSRecirculationMode)
Chapter1ProductCharacteristics
Preheat or Internal Recirculation Mode may
be used without an installed recirculation
pipe. The water heater is preheated and
protected from freezing.
Preheat or Internal Recirculation Mode
Air & Gas
Mixing
Primary heat
exchanger
Burner
Secondary heat
exchanger
Recirculation
Pump
Pressure Relief Valve
Hot Water Oulet
Condensate Hose
Cold Water Inlet
Gas
Expansion Tank (Install
according to local code)
bYPS Recirculation Mode may be used with
a cross over valve assembled at the furthest
tting
Pressure Relief Valve
Air & Gas
Mixing
Primary heat
exchanger
Secondary heat
exchanger
Burner
Recirculation Line
Expansion Tank (Install
according to local code)
Recirculation
Pump
Condensate Hose
Gas
Hot Water Outlet
Cold Water Inlet
Cross Over Valve
Primary heat
exchanger
Burner
Air & Gas
Mixing
Recirculation
Pump
Secondary heat
exchanger
Pressure Relief Valve
Hot Water Oulet
Condensate Hose
Cold Water Inlet
Gas
Expansion Tank
(Install according to local
code)
Cross Over Valve
bYPS Recirculation Mode with Cross
Over Valve
Recirculation Line

13
FAN
FAN
FAN
1s1.5s2s
30s
1s1.5s2s 10s1.5s2s
■NormalIgnition
■NormalShutdown
■IgnitionFailure(ErrorCodeafter10times)
IGNITION
IGNITION
IGNITION
GASVALVE
GASVALVE
GASVALVE
FLAME DETECTION
FLAME DETECTION
FLAME DETECTION
TimingLogic
Chapter1ProductCharacteristics

14
Shutdown procedure
Ignition operation
POWER S/W ON
AGM Zero Position setting
Water Flow Control Valve
Zero Position setting
Bypass Flow Control Valve Zero Position setting
Initial check
check
Thermostat communication fault
H/L : Over-heating fault
flow control valve error
Mixing valve error
AGM error
Water leakage is detected error
NO
YES
NO
NO
76
67
HX Thermistor
Open or shorted
Exhaust Temp Thermistor
Open or shorted
Flame Signal Detected
before Ignition
Circuit Board
abnormality
Hot Water Thermistor
Open or shorted
Cold Water Thermistor
Open or shorted
HX Themistor or
Hot Water abnormality
NO
YES
Gas Solenold Valve closed
Flame sensor does not detect
a flame(More than DC 2.5V)
Hot water fixture opened
Pre-heating selection
Water Flow Sensor
detected > 0.5 GPM
Initial check normal
Inlet water high
temperature check
nomal
Fan Motor turn ON
Fan speed
(Feedback signal)
Re-ignition
(10 time or less)
Pre-heating Start
Igniter sparks
Gas Solenold Valve Opens
Flame signal
≤ DC 2.5V
Fan Motor RPM Control
Burner On Indicator lit
Igniter stops sparking
Burner On Indicator goes Off
Burner ON Indicator goes Off
At Max, BTU is
outlet water temp,
less than setting
Proportional control(gas and fan)
Water Flow Control Valve activates
Safety device
triggered
Igniter stops sparking
Gas Solenold Valve Opens
Igniter stops sparking
Flame signal
≤ DC 2.5V
Re-ignition
(8 time or less)
Extinction
(8 time or less)
High Limit switch
normal
Igniter sparks
Burner Limit
switch normal
YES
NO
Fan Motor stops
Post_purge time ≥ 30
Sec
Water flow control valve activates to
mid position
Safety device
triggered
Shutdown
Hot water fixture closed
Water Flow Sensor
detected > 0.4 GPM
Burner On Indicator goes off
Gas Solenoid Valve closes
NO
YES
YES
NO
Ignition operation
Fan Motor turn ON
Fan speed
(taget ±500rpm)
Igniter sparks
Gas Solenoid Valve opens
NO
YES
Water flow control valve activates to
mid position
Fix problem
Disconnect power
Error codes stops flashing
Power On/Off button turn OFF
Hot water fixture closed
Fan Motor stops
When the exhaust gas temperature is
greater than 149℉(65℃)
Flame Detected before Ignition
Important EPROM Data or Safe Data
Abnormal
APS/Condensate –Open is Fault
Cold WaterThemistor
Open or shorted
Hot Water Thermistor
Open or shorted
HX Themistor
Open or shorted
Exhaust Thermistor
Open or shorted
Flame Detected after Exiting
a Flame On Condition
Fan abnomality
HX Themistor or
Hot Water abnormality
Gas Leakage is Detected
No water in Heat Exchanger
44
YES
NO
Power On/Off button turn OFF
Power Lamp light
Gas Solenold Valve closed
Flame sensor does not detect
a flame(More than DC 2.5V)
YES
NO
YES
NO
YES
YES
NO
YES
NO
YES
NO
YES
NO
NO
YES
YES
NO
NO
YES
YES
YES
NO
NO
YES
Circulation Pump Abnormality
Piping establishmet Abnormality
20
45
66
65
16
31
32
33
35
72
73
61
11
16
29
31
12
12
20
43
32
33
35
38
40
39
60
94
70
72
41
HotWaterModeFlowChart
Chapter1ProductCharacteristics
(taget±1000rpm)
YES
10
10

15
Chapter1ProductCharacteristics
Water leakage operation flow
Pre-heating mode operation flow
Freeze Prevention control flow
Circulation Pump Shutdown
Freeze Prevention control condition
Water leakage
abnormal
Water Flow Control Valve closed
NO
Circulation Pump Shutdown
YES
HX Themistor Temp
≤ 46 ℉(8℃)
YES
NO
YES
YES
NO
HX Thermistor Temp
≤ 41 ℉(5℃)
HX Thermistor Temp
normal
HX Thermistor Temp
≤ 46 ℉(8℃)
Combustion proceed
HX Thermistor Temp
≥ 50 ℉(10℃)
HX Thermistor Temp
≥ 104 ℉(40℃)
Hot Water Thermistor normal
Hot Water Thermistor
Temp
≤ 46 ℉(8℃)
NO
Circulation Pump Running
Hot Water
Thermistor Temp
≤ 50 ℉(10℃)
Circulation Pump Shutdown
YES
NO
YES
NO
YES
NO
NO
YES
YES
NO
Exit Combustion
Circulation Pump Running
Circulation Pump Shutdown
YES(Burner ON)
Error occurs 44
Pre-heating mode
Temp setting -Δt≥ HX
Thermistor Temp
HX Thermistor Temp ΔT
(=Max Temp-Min Temp)
<Δ5℉(3℃)
Pre-heating Start
Error count ≥ 2 time
NO
YES
YES (Burner OFF)
NO
YES
Pre-heating Stop
NO
ΔT Setting -Install mode (HT) : LO [27℉(15℃)]
HI-1 [18℉(10℃)]
HI-2 [ 9℉( 5℃)]
Temp setting ≤ HX
Thermistor Temp
NO
FreezeProtectFlowChart
►FreezePreventioncontrol󰘱ow ►Waterleakageoperationflow
►Pre-heatingmodeoperationflow

16 Chapter1ProductCharacteristics
WiringDiagram
CN11
CN9
CN10 CN12
CN8
CN1
CN14
CN4
CN5
CN7
CN3

17
Chapter1ProductCharacteristics
LadderDiagram

18 Chapter1ProductCharacteristics
CONNECTOR
DESCRIPTION HT SELV
NO. OF LOCATION PIN BOARD SILK
CN9
65001WS-12
1 - EARTH GROUND -
2L Power Supply Line HT (120V~)
3CP1 Circulation Pump
4IT Igniter
5L(HT) UNUSED
6GV Gas Valve
7UNUSED
8
N Power Supply Neutral
9-12
N
AC Power COM Line
CN1
SMW250-03
1
RS-485
RS485 + SELV (5V)
2GND
3RS485 -
CN4
LWD1140-06
1
FAN
Unused -
2GND SELV (30V)
3VDD SELV (14V)
4Fan power (start coil) SELV (30V)
5Fan power (end coil)
6Fan speed feedback signal SELV (5V)
CN8
SMW250-04
1
MCU ISP
GND
SELV (5V)
2ISP / Reset Port
3ISP TOOL0 Data Port
4VCC
CN11
1
HWL Unused
SELV(12V~)
9
2LWL Water Leak Sensor
10
3HD Unused
11
4TH Connect to the Display Control
(Thermostat)
SELV (14V)
12
5
Condensate APS Condensate Air Pressure Switch
13
6Flue APS Unused
14
7BL Burner Limit
15
8HL Water High Limit
16

19
Chapter1ProductCharacteristics
CONNECTOR
DESCRIPTION HT SELV
NO. OF LOCATION PIN BOARD SILK
CN7
LWD1140-14
1F.S Flame Detect Sensor
SELV (5V)
8
2OP.S Operating Water Temperature Sensor
9
3DH.S DHW Temperature Sensor
10
4I.S Inlet Water Temperature Sensor
11
5
BG.S
Exhaust Temperature Sensor
12
6
OT.S
Optional Temperature sensor
13
7
SP.S
Unused
14
CN12
SMW250-07
1
AGM
AGM Stepper Motor Coil / Y Phase
SELV (24V)
2
3AGM Stepper Motor Coil / X Phase
4
5 GND -
6 AGM Stepper Motor Position SELV (14V)
7 VDD SELV (24V)
CN10
SMW250-08
1
DHM
(Mixing Valve)
DHM Stepper Motor Coil / Y Phase
SELV (14V)
2
3DHM Stepper Motor Coil / X Phase
4
5 GND
6 DHM Stepper Motor Position
7Unused
8 VDD
CN14
SMW250-09
1
IWC
(Flow Control
Valve)
GND
2 IWC Stepper Motor Position
3 VDD
4 IWC Stepper Motor Coil X Phase
5 IWC Stepper Motor Coil Y Phase
6 VDD
7 IWC Stepper Motor Coil / X Phase
8IWC Power IWM Stepper Motor Coil / Y
Phase
9Unused -

20 Chapter1ProductCharacteristics
CONNECTOR
DESCRIPTION HT SELV
NO. OF LOCATION PIN BOARD SILK
CN3
SMW250-06
1OPB Optional Push Button SELV(5V)2
3Unused
4
FLUX1
VCC
SELV (5V)
5 Water Flow Sensor
6 GND
CN5
SMW250-10
1RPM Fan RPM Check
2 GND