STIEBEL ELTRON IM 45 EC User manual

1
Service Manual
IM_EC
Author: Mr. Apiwat Limrueangwattanakul
Date: MAY 2015
Revision: version 0

2
Table of Contents
Warning.......................................................................................................................................................... 3
General product information......................................................................................................................... 4
Technical data ................................................................................................................................................ 5
Wiring Diagram ...............................................................................................................................................
Troubleshooting..............................................................................................................................................
Root clause analysis ........................................................................................................................................
1. Heating Elements checking.................................................................................................................
2. TRIAC checking.................................................................................................................................. 
3. Flow Switch checking ........................................................................................................................ 
4. Control PCB checking ........................................................................................................................ 
5. Thermostat checking......................................................................................................................... 
6. ELCB checking.................................................................................................................................... 
7. ELCB function testing ........................................................................................................................ 
8. System comfirm ................................................................................................................................ 

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

4
General product information
The STIEBEL ELTRON IM flow-controlled, pressurized instantaneous water heater heats the water
while it is flowing through the unit. The heating power is switched on automatically in the event of the


5
Technical data
Model
IM 45EC
IM 60EC
IM 80EC
Type
Closed outlet
Min. inlet water pressure MPa(bar)
0.015(0.15)
0.02(0.2)
0.03(0.3)
Max. inlet water pressure MPa(bar)
1(10)
Water connection
G 1/2"
Electrical connection

220 V
kW
4.5
6.0
8.0
230 V
kW
4.9
6.6
8.7
240 V
kW
5.4
7.1
9.5
Recommended cable size Sqmm.
2.5 - 4.0
4 6
6 8
Recommended circuit breaker A
25
32
40
Dimension (W x H x D) mm.
186 x 164 x 76

6
Wiring Diagram
Type DX…E
A = Heating element
B = Electronic control set (Phase Cut)
C = ELCB
D= Triac Set
E = Thermal cut - out (TCO)
E
B
A
D
C

7
Troubles shooting
- ELSD cut-off
- Check filter, and flow
rate
-Low flow
- No power supply to unit
- Power line not tight
- Check breaker
- Thermal cut-out (TCO)
- Check Triac set
- Check Reed switch
- Cleaning magnet
- Check PCB
- ELSD reset
- Check connecting
points and fix.
Power lamp not "ON"
and water not hot
- PCB failure
- Check PCB
- Missing water connection
- Check reed switch
- Reed switch failure
- Check Triac set
- Triac failure
Problem & Condition
Cause
Correction
- Reconnect inlet,
Power lamp "ON"
but water not hot
- Heating elements failure
- Check Heating
Power lamp not "ON"
but water Hot
- Lamp broken
- Lamp cable broken
- Check & change the Lamp
- Check & change Lamp
cable
Power lamp "ON" all the
time
- Reed switch failure
- Check reed switch
- Triac short circuit
- Check Triac set

8
Problem & Condition
Cause
Correction
- Overloaded current on main
breaker
- Power line wrong connection
- Turn off other appliance
- Reconnect power
- Water over flow
- Reduce water flow
Breaker cut-off
- Reed switch failure
Water temperature
not constant
- Change pump to
smooth pressure type
- Check reed switch
- Irregular water flow
- Triac failure
- Check Triac set
Water leak
- Wrong installation
- Reinstallation
- Connector has loosen
- Tight connectors
- PCB failure
- Check PCB
Power on maximum but
water not hot enough
Water too hot
Troubles shooting

9
Root clause 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 Mu)))) "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, "alog Multimeter
Pole - Tank (P1 - Tank), (P2 Tank) and (P3 Tank)
Tank
P2
P3
Tank
Tank
P1
Pole Pole (P1 - P2), (P1 P3) and (P2 P3)
P2
P1
P3
P2
P3
P1

10
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.
- )))) " 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, "ultimeter.
GRD
L1
H1
H1 - GRD
H1
GRD
Pole Ground
(L1 GRD) &
(H1 GRD)
L1 - GRD
L1
GRD