STIEBEL ELTRON EVS15 User manual

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Service Manual
EVS15, EVS30, EVS50, EVS80, EVS100, EVS150
Author: Mr. Pornpawit Pumyaem
Date: 24 June 2016
Revision: version 1

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

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Table of Content

General Product 




1.Heating Elements 
2.Thermostat 
3.Thermo cut out Checking
4.Anode 


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General product information
The EVS 15-150 unvented (pressurized) wall-mounted water heater can heat potable water up to
about EVS 15-150 = 75°C to suit demand and supply a number of draw-off points. The water content is
automatically heated to the preset temperature. The device is adjusted at the works to 75°C.

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Technical data
Model
EVS15
EVS30
EVS50
EVS80
EVS100
EVS150
Type
Close
Outlet pressure
0.7 Mpa (7 bar)
Water Connector
G 1/2"
Power Supply
1/N/PE AC 220-240V
Rated frequency
50-60 Hz
220 V
kW
1.5
2.0
230 V
kW
1.63
2.18
240 V
kW
1.78
2.38
Cable Size (Sq.mm)
2.5-4
Circuit Breaker (A)
10
15
Thermal cut out (TCO)
Manual Reset ( 93°C +2°C / -5°C )
Thermostat
30°C to 75°C
Insulation layer
Polyurethane
Anode
Magnesium stick
Dimension (mm)
Ø305x543
Ø365x611
Ø390x745
Ø460x 740
Ø460x880
Ø460x1230
Unit weight (kg)
10.8
12.6
17.1
23.3
27.6
37.9

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Wiring Diagram
A = Heating element
B = Thermostat
C = Thermal Cut - Out (TCO)
A
B
C

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Troubleshooting
Problem & Condition
Cause
Correction

And water not hot
- No power supply to unit
- Check breaker
- Power line loose at contact
points
- Check connection points and fix
- Thermal cut-out (TCO)
- Reset Thermal cut out
- Check Thermostat
Power lamp "ON"
But water not hot
- Heating element broken
- Check heating elements
Power lamp not "ON"
But water Hot
-LED broken
- Change the new LED
Breaker cut-off
(Main breaker)
- Overloaded current on main
breaker
- Turn off other appliances
- Power line wrong connection
- Replace main breaker
- Reconnect power line L, N, G
Water leak
- Connector has loosen
- Tight connectors or change
rubber seal
- Wrong installation
- Reinstallation

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Cause Analysis
1. Heating Elements Checking
Definition: Heating element is a metal coil that heats up to high temperatures when electricity
is applied.
-Disconnect cables to the elements.
- Set Multi )))) 
Check
Meter Result
Cause
Action
Pole-Pole
"Beep" signal " )))) "
Pass
No action
No signal "OL" or (
Element Broken
Change New Heater
Pole-Case
"Beep" signal " )))) "
Element Broken
Change New Heater
No signal "OL" or (
Pass
No action
Remark: "OL" = Over Load For Digital multimeter
And "For Analog multimeter
Pole -Pole
Pole -Case
Case
Pole
Pole 1
Pole 2

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2.Thermostat Checking
Definition: A thermostat is a component which senses the temperature of a system so that the
system's temperature is maintained near a desired set point.
- Disconnect cables as in the picture.
- Set Multi )))) " and check on poles.
-Position ON
Check
Meter Result
Cause
Action
Pole - Pole
"Beep" signal " )))) "
Pass
No action
No signal "OL" or (
Connector open
Change new one
-Position OFF
Check
Meter Result
Cause
Action
Pole - Pole
No signal "OL" or (
Pass
No action
"Beep" signal " )))) "
Connector open
Change new one
P1
P2
Power
ON Min. Power
Max. Power

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3.Thermo cut-out Checking
Definition: The thermal cut out is a sensor with a closed circuit (NC). It will automatically cut out
power system when the water in tank up to 93 
C. To check the thermal cut out, follow the
steps below.
- Disconnect cables as in the picture.
- Set Multi )))) " and check on poles.
P1-P2 P3-P4
Check
Meter Result
Cause
Action
Pole 1- Pole 2
Pole 3 - Pole 4
"Beep" signal " )))) "
Pass
No action
No signal "OL" or (
Connector open
Reset manual button*
*Note: In case the thermo cut-out cannot reset, it must be replaced.
Manual reset
P1
P2
P3
P4

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4.Anode Checking
Magnesium Anode
Definition: Magnesium Anode is insulate metal corrosion rust and slag.
- Disconnect cables as in the picture.
- Remove Heating element set and check as shown in the pictures.
EVS 15-150
Check
Result
Cause
Action
Magnesium
Anode
A
Pass
No Action
B
Not Pass
Change new one
Anode
A: New Anode
B: Old Anode

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5. System Confirm
Ensure that you have tightened all the screws back into their original positions. 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 OFF 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. If no water leaks where discovered turn the breaker on.
4. Try to adjust knob (Temperature). If the water is warm the unit is ready to use.

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