STIEBEL ELTRON AQ 35 E-2 User manual

1
Service Manual
AQ 35,45 E-2
Author: Mr. Apiwat Limrueangwattanakul
Revision: version 1.0

2
Table of Contents
Warning ......................................................................................................................................................... 3
General product information......................................................................................................................... 4
Technical Data................................................................................................................................................ 5
Wiring Diagram .............................................................................................................................................. 6
Troubles shooting .......................................................................................................................................... 7
Root Cause Analysis ....................................................................................................................................... 8
1. Heating Elements Checking ............................................................................................................... 8
2. TRIAC Checking .................................................................................................................................. 9
3. Flow Switch Checking....................................................................................................................... 10
3.1) Set unit at vertical direction ......................................................................................................... 10
............................................................................. 11
3.3) The other way to activate Flow Switch......................................................................................... 12
4. PCB Control Checking....................................................................................................................... 13
5. Thermostat Resetting ...................................................................................................................... 14
6. System Confirm................................................................................................................................ 15
7. AQ (E) Parts List................................................................................................................................ 16
7.1 Spare Parts list, Model: AQ 35E ..................................................................................................... 17
7.2 Spare Parts list, Model: AQ 45E ..................................................................................................... 18
7.3 Spare Parts list, Model: AQ 60E ..................................................................................................... 19

3
Warning
Warning: This service manual is suitable for qualified Technicians only.
Warning: Disconnect power supply before open cover.

4
General product information
The AQUAPOWER pressure less (opened outlet) small instantaneous water heater that is
device to heating water for shower. The electrical power is electronically controlled. The flow is
switched on and off by using a water valve.
The unit switches the power on once the flow volume is sufficient. The "Power" light indicates
that the unit is switched on. Any desired temperature can be set by turn right of rotary switch,
The AQ_E-2 model is fitted with an overheating protection device. In the event of overheating
the heating power will be cut off.

5
Technical Data
Model
AQ 35E-2
AQ 45E-2
Type
Opened outlet
Outlet Pressure
0 Mpa (0 bar)
Water Connector
G 1/2"
Power Supply

- Rated Power @ 220 V (kW/A)
3.5-15.29
4.5-20.5
- Rated Power @ 230 V (kW)
3.8-16.5
4.9-21.3
- Rated Power @ 240 V (kW)
4.2-17.5
5.4-22.5
Cable Size (Sq.mm)
2.5-4.0
2.5-4
Circuit Breaker (A)
20
25
Dimension H x W x D (mm)
200 x 360 x 110
Unit weight (kg)
1.2

6
Wiring Diagram
Type AQ...E-2
A = Heating element
B = Electronic control set (Phase Cut)
C = ELSD Circuit (Option)
D= Single Triac Set
E = Thermal cut - out (TCO)
F = Button Board (Option)
G = Current Leakage Sensor (Option)
G
E
A
D
B,C
F

7
Troubles shooting
Problem & Condition
Cause
Correction
Power lamp not "ON"
And water not hot
- No power supply to unit
- Low flow
- Power line not tight
- Check breaker
- Check connect points and fix
it.
- Check filter, and flow rate
- Reconnect inlet, outlet
- Check Reed switch set
- Check Thermostat
- Missing water connection
- Reed switch failure
- Triac failure
- Thermal cut-out (TCO)
- Check Triac set
- Heating element broken
- Check heating elements
Power lamp "ON"
But water not hot
Water leak
- Tight connectors
- Connector has loosen
- Wrong installation
- Reinstallation
- Lamp broken
- Lamp cable broken
- Check & change the Lamp
- Check & change Lamp cable
Power lamp not "ON"
But water Hot
Water too hot
- Check Reed switch set
- Reed switch failure
- Triac failure
- Check Triac set
- Heating elements failure
- Check heating elements
- Check Reed switch
- Reed switch failure
Power on maximum but
water not hot enough
- Irregular water flow
- Change pump to smooth
pressure type
Water temperature
not constant
- Overloaded current
on main breaker
- Turn off other appliances
- Change main breaker
Breaker cut-off
- Power line wrong connection
- Reconnect power line L, N, G

8
Root Cause Analysis
1. Heating Elements Checking
Definition: Heating Element is a metal coil that heats up to high temperatures, when
electricity is applied. To check the Heating Element, follow the steps below:
- Disconnect cables from the Elements.
- Set Multi )))) "and check as show in the pictures.
Check
Meter Result
Cause
Action
Pole Pole
"Beep" signal or (~ 0 )
Element Pass
No action
No signal "OL" or (
Element Broken
Change New Heater
Pole GRD
"Beep" signal or (~ 0 )
Element short to tank
Change New Heater
No signal "OL" or (
Element Pass
No action
Remark: "OL" = Over Load for Digital Multimeter, "Multimeter
Pole - Pole (P1 - P2)
P1
P2
Pole - GRD (P1 - GRD) or (P2 - GRD)
Or
GRD
P1
P2
GRD

9
2. TRIAC Checking
Definition: The Triac is a three-terminal device, which controls and conducts current flow during
both alternations of an AC cycle. To check Single Triac, follow the steps below:
- Disconnect cables and unplug any connectors in red circle.
- Set Mu)))) " and check as show in the pictures.
Note; L1 = line, H1 = Heater, GRD = Ground
Check
Meter Result
Cause
Action
L1 H1
"Beep" signal or (~ 0 )
Triac short circuit
Change new
No signal "OL" or (
Triac Pass
No action
Check
Meter Result
Cause
Action
L1 - GRD
"Beep" signal or (~ 0 )
Triac short circuit
Change New Triac PCB
No signal "OL" or (
Triac Pass
No action
H1- GRD
"Beep" signal or (~ 0 )
Triac short circuit
Change New Triac PCB
No signal "OL" or (
Triac Pass
No action
Remark: "OL" = Over Load for Digital Multimeter, "r
GRD
L1
H1
GRD
H1
L1
GRD
Poles - Ground

10
3. Flow Switch Checking
Definition: Flow switch (Reed SW.) is a vacuum tube with two thin metallic strips at open circuit
(NO) configuration while on standby. It activates or goes on close circuit by use of a magnet.
3.1) Set unit at vertical direction
Simulate like a unit standby Flow Switch (Reed SW.) still open circuit (as no water supply).
- Set Multi )))) " and unplug the reed switch connector from the
Control PCB and check Reed Switch as in the pictures.
Check
Meter Result
Cause
Action
Pole - Pole
"Beep" signal or (~ 0 )
Reed SW. contact closed
Change new one*
No signal "OL" or (
Pass
No action
Remark: "OL" = Over Load for Digital Multimeter, "
* Note: Recommend replacing magnet set at the same time.
Pole - Pole

11
3.2) Set unit to upside down (turn 180 ˚) direction
Simulate like a unit working by activate Flow Switch (Reed SW.) become close circuit.
Check
Result
Cause
Action
Pole - Pole
"Beep" signal or (~ 0 )
Pass
No action
No signal "OL" or (
Reed SW contact closed
Change new one*
Remark: "OL" = Over Load for Digital Multimeter, "Multimeter
*Note: Recommend replacing magnet set at the same time.
Pole - Pole

12
3.3) The other way to activate Flow Switch.
Check
Result
Cause
Action
Pole - Pole
"Beep" signal " )))) "
Pass
No action
No signal "OL" or (
Reed SW not activate
Check Magnet
Remark: "OL" = Over Load for Digital Multimeter, "Multimeter
Pole - Pole
Used Magnet to activate
unit

13
4. PCB Control Checking
Check
Result
Cause
Action
Visual
Electronic equipment burn
PCB short circuit
Change new one
No visible damage
PCB failure
Change new one
Visual check

14
5. Thermostat Resetting
Double Action Thermostat
Definition: Double Action Thermostat will automatically cut out the power system when
the water in tank rise to , if watertemperature down lower than 4 it become connect
power system again.
In case temperature high up with any abnormal case until 7, it will fully cut out the power.
The technician must fix! Root cause first before reset the button.
*Note: Please ensure every step has been completed before resetting the Thermostat.
In case the Thermostat cannot reset, it must be replaced.
Thermostat Resetting
(For AQ 35E)

15
6. System Confirm
This final test must be performed after repairing the unit. If all steps below are working
correctly the unit can be returned to the end user.
1. If available, set the unit in test station and turn the knob to the MIN position.
2. Connect electricity wiring to the unit and connect the water valve, then supply water to the
system to check for leaks but keep the main breaker to the unit turned off.
3. Check leak point by visual. If have some leak, please change O-Ring or gasket. ***
If Power Lamp on mean Triac Damage. Must change new one***
4. Continuous supply electricity and turn knob control on.
5. Turn right knob control to select temperature that you desire.
6. Check temperature by warmed water ready for use.
7. The confirmation process by checking on the approximate temperature of the water.
8. Finalize, Purge water in tank by air blow until dry.
***Remark: Change inlet for the whole set see in spare parts list.
Visual check

16
7. AQ_E-2 Parts List

17
7.1 Spare Parts list, Model: AQ 35E
2
(Effective since October 2005)
Item
Part no.
Part name
Quantity
Remark
1
6701-269827
Filter Thai
1
2
4401-269842
Reed Switch Housing Wire, Black
1
3
7701-269562
O-Ring 8 * 1.5
1
4
6301-269820
Plastic Flow Body 15 mm., Black
1
5
4301-269740
Magnet Set (B+M+P)
1
Replaced 4301-281930
6
7701-269564
Silicone Gasket 12 * 20 * 4
1
7
6201-275934
Triac PCB BTA 24 # 14 Plug With Transil Diode
1
8
6801-269832
Cooling Plate
1
9
7701-269563
O-Ring 21.3 * 1.8
1
10
4301-281686
Black Plastic Inlet Set, For Copper Tank
1
11
7701-269559
Silicone Gasket 12 * 18.5 * 2.5
1
20
6102-267317
Copper Tank VBC, Dia 54*127, 1E (3.5 Kw)
1
21
7501-269439
Tank Sticker 3.4 X 1.7 Cm 1.5"
1
22
6801-267320
Bracket For Copper Tank Dai. 54 mm
1
25
6201-275552
Double Action Thermostat 16A For Copper Tank
1
26
6801-267307
Thermostat Bracket
1
30
6201-267393
Control PCB PC-CB With ELSD
1
31
6201-267389
Button PCB DS
1
35
6301-165511
Plastic Nipple/Adapter
1
Effected since
November 2009
6302-165511
Plastic Nipple/Adpter G 1/2"
1
Replaced by
6301-165511
36
7701-165828
O-Ring 9 * 2.5
1
37
7801-269566
Clip Lock
1
45
6301-271088
Knob Set Thai
1
STE
6301-271295
Knob AEG / MST Set Thai
1
AEG
46
6301-267373
Knob Lock Thailand
1
47
6501-275926
Front Sticker AQ 35 E (STE)
1
STE
6501-267322
Front Sticker AQ 35 E
1
AEG
48
6301-267383
Plastic Cover Thailand DS
1
STE
6301-269707
Plastic Cover - AEG
1
AEG
49
6301-267346
Base Thailand
1
50
6001-158869
Cable Entry Rubber Seal
1
55
6302-281966
Terminal Block TLB-500W-0392-3P-XS
1
56
6301-269818
Plastic Insert Support PCB
2
57
7302-161911
Spacer
2
Replaced by
7301-281813
7301-281813
PCB Spacer
2
Effected since
January 2009
58
6301-267372
Plastic Knob Adapter Thailand
1

18
7.2 Spare Parts list, Model: AQ 45E
(Effective since October 2005)
Item
Part no.
Part name
Quantity
Remark
1
6701-269827
Filter Thai
1
2
4401-269842
Reed Switch Housing Wire, Black
1
3
7701-269562
O-Ring 8 * 1.5
1
4
6301-269820
Plastic Flow Body 15 mm., Black
1
5
4301-269740
Magnet Set (B+M+P)
1
Replaced 4301-281930
6
7701-269564
Silicone Gasket 12 * 20 * 4
1
7
6201-275935
Triac PCB BTA 24 # 14 Ring With Transil Diode
1
8
6801-269832
Cooling Plate
1
9
7701-269563
O-Ring 21.3 * 1.8
1
10
4301-281686
Black Plastic Inlet Set, For Copper Tank
1
11
7701-269559
Silicone Gasket 12 * 18.5 * 2.5
1
20
6102-267318
Copper Tank VBC, Dia 54*127, 1E (4.5 Kw)
1
21
7501-269439
Tank Sticker 3.4 X 1.7 Cm 1.5"
1
22
6801-267320
Bracket For Copper Tank Dai. 54 mm
1
25
6202-275484
Double Action Thermostat For Copper Tank 45A
1
26
6801-275556
Bracket For Thermostat 25A/45A For Copper Tank
1
30
6201-267393
Control PCB PC-CB With ELSD
1
31
6201-267389
Button PCB DS
1
35
6301-165511
Plastic Nipple/Adapter
1
Effected since
November 2009
6302-165511
Plastic Nipple/Adpter G 1/2"
1
Replaced by
6301-165511
36
7701-165828
O-Ring 9 * 2.5
1
37
7801-269566
Clip Lock
1
45
6301-271088
Knob Set Thai
1
STE
6301-271295
Knob AEG / MST Set Thai
1
AEG
46
6301-267373
Knob Lock Thailand
1
47
6501-275927
Front Sticker AQ 45 E (STE)
1
STE
6501-267323
Front Sticker AQ 45 E
1
AEG
48
6301-267383
Plastic Cover Thailand DS
1
STE
6301-269707
Plastic Cover - AEG
1
AEG
49
6301-267346
Base Thailand
1
50
6001-158869
Cable Entry Rubber Seal
1
55
6302-281966
Terminal Block TLB-500W-0392-3P-XS
1
56
6301-269818
Plastic Insert Support PCB
2
57
7302-161911
Spacer
2
Replaced by
7301-281813
7301-281813
PCB Spacer
2
Effected since
January 2009
58
6301-267372
Plastic Knob Adapter Thailand
1

19
7.3 Spare Parts list, Model: AQ 60E
(Effective since October 2005)
Item
Part no.
Part name
Quantity
Remark
1
6701-269827
Filter Thai
1
2
4401-269842
Reed Switch Housing Wire, Black
1
3
7701-269562
O-Ring 8 * 1.5
1
4
6301-269819
Plastic Flow Body 16 mm., Black
1
5
4301-269709
Magnet Set (P+M+P)
1
6
7701-269564
Silicone Gasket 12 * 20 * 4
1
7
6201-275936
Triac PCB BTA 41 # 12 Ring With Transil Diode
1
8
6801-269832
Cooling Plate
1
9
7701-269563
O-Ring 21.3 * 1.8
1
10
4301-281686
Black Plastic Inlet Set, For Copper Tank
1
11
7701-269559
Silicone Gasket 12 * 18.5 * 2.5
1
20
6102-267319
Copper Tank VBC, Dia 54*127, 1E (6.0 Kw)
1
21
7501-269439
Tank Sticker 3.4 X 1.7 Cm 1.5"
1
22
6801-267320
Bracket For Copper Tank Dai. 54 mm
1
25
6202-275484
Double Action Thermostat For Copper Tank 45A
1
26
6801-275556
Bracket For Thermostat 25A/45A For Copper Tank
1
30
6201-267393
Control PCB PC-CB With ELSD
1
31
6201-267389
Button PCB DS
1
35
6301-165511
Plastic Nipple/Adapter
1
Effected since
November 2009
6302-165511
Plastic Nipple/Adpter G 1/2"
1
Replaced by
6301-165511
36
7701-165828
O-Ring 9 * 2.5
1
37
7801-269566
Clip Lock
1
45
6301-271295
Knob AEG / MST Set Thai
1
AEG
46
6301-267373
Knob Lock Thailand
1
47
6501-267324
Front Sticker AQ 60 E
1
AEG
48
6301-269707
Plastic Cover - AEG
1
AEG
49
6301-267346
Base Thailand
1
50
6001-158869
Cable Entry Rubber Seal
1
55
6302-281966
Terminal Block TLB-500W-0392-3P-XS
1
56
6301-269818
Plastic Insert Support PCB
2
57
7302-161911
Spacer
2
Replaced by
7301-281813
7301-281813
PCB Spacer
2
Effected since
January 2009
58
6301-267372
Plastic Knob Adapter Thailand
1