VESTEL TRV 50 User manual

THERMOSIPHON
SERVICE MANUAL

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CONTENTS PAGE
1. FEATURES 3-4
2. COMPONENTS
•Boiler 4-5
•External Body 5
•Insulation 5
•Resistance 5
•Flash Gasket 5
•Thermostat 5-6
•Electronic Thermostat 6-7
•Limit Thermostat 7
•Safety Valve 7
•Anode 7-8
•Cable Connection Schematics 9
3. OPERATION PRINCIPLE
•Operation 9
•Stratification of Cold and Hot Water Layers 9
4. PLUMBING
•Placement and Plumbing of the Unit 10
5. MAINTENANCE
•Cleaning the Resistance of Boiler Scale 10-11
•Resistance inspection 11-12
•Fault Detection Chart 12-13

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1. THE FEATURES OF ELECTRICAL TANK THERMOSIPHON
Safety: Each part of the thermosiphon is controlled very precisely in order to achieve operation
continuity on perfect level. Electric circuit is completely isolated from the water circuit. All models
are equipped with at least 3 safety mechanisms.
Ease of use: All models can be mounted on any desired location easily.
Low heat loss: It is preferred that the thermosiphons, which can be mounted anywhere, are located
closely to the hot water point as much as possible, so that the heat loss in the plumbing is kept at
minimum.
Low amount of hot water: In order to prevent unnecessary waste of energy, the models
manufactured in different capacities are designed for locations like kitchen or service room that need
little but constant hot water.
(1) Efficient insulation, low energy consumption.
High density, thick polyurethane foam layer provides perfect insulation for all electrical heaters and
significantly decreases energy consumption.
(2) Long life boiler.
A special enamelling process is used to protect the tank against the corrosive effect of the water and
water-soluble materials. The said protection ensures the boilers' long-life and reliability.
(3) Magnesium anode.
An electrochemical corrosion preventive system is used, which improves boiler life by using more
magnesium anode in the products. Besides, the anode is placed into the boiler so that it can be
accessed easily when needed for inspection and parts replacement.
(4) High quality heating elements.
Resistances are manufactured from first class materials to guarantee long life of use.
(5) Water temperature control.
Products have a temperature control knob that enables the temperature value to be kept between
35°C and 80°C. Thanks to this knob, each user can select the water temperature they require and thus
save energy.
(6) Thermostat.
Thermosiphons are equipped with original thermostats that guarantee high performance and
maximum safety. In electronic models, circuit board takes over for the thermostat.
(7) Limit thermostat.
Thermostats are equipped with “maximum temperature” thermostat. This safety mechanism disables
the main thermostat and resistance in case of a malfunction.
(8) Pressure safety valve.
Thermosiphons are equipped with a safety valve that is approved by the standards regarding pressure
value. A latch-type wall is used that allows unit draining without requiring to remove the discharge
pipe.
(9) Freezing Safety.
When the temperature of the water inside your thermosiphon falls below 5°C, the heater resistance
automatically activates and heats the water up to 16°C. All the while, the lamp that has Anti Ice and
resistance symbols turn on and display the water temperature.
Your thermosiphon must be in stand-by mode for the freezing safety system to activate. Install your
thermosiphon to a location without freezing risk.
“This safety system is present in only electronically controlled models.”

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(10) Bacteria Prevention System.
Researches show that when water remains stagnant under 600C for a prolonged duration, the conditions
become suitable for bacteria reproduction.To prevent this, your thermosiphon raises the water
temperature to 65°C at least once a week while in stand-by mode and keeps the water at this
temperature at this level for one hour.
“This safety system is present in only electronically controlled models.”
(11) Anhydrous Operation Safety.
When your device is operated without water for any reason, system will be automatically activated and E3
error code will be generated on display.In this case, ensure that your water heater is filled with water by
cutting energy supply from V-automate.After ensuring that water is filled, if you re-provide energy supply,
thermosiphon will continue normal operation.
“This safety system is present in only electronically controlled models”
(12) Low Voltage Protection.
If the supply voltage decreases down to a level that may damage device during mains fluctuations, low
voltage protection system will activate and E2 error will be generated on display.When the voltage goes back
to the desired value, E2 code will disappear and device will resume operation.
“This safety system is present in only electronically controlled models”
(13) Technical Specifications.
2. COMPONENTS OF THE ELECTRICAL THERMOSIPHON
2.1 BOILER
Thermosiphon boiler is manufactured from steel sheets suitable for enamelling. Interior is coated
with titanium-added enamel that withstands water at 850°C.

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(1) Upper camber
(2) Hot water exit pipe. Hot water exit pipes of different dimensions can be used according to the
model. Hot water is always extracted from the top portion of the tank.
(3) Lower camber
(4) Boiler flash
(5) Cold water Inlet pipe
(6) Entrance diffuser. Prevents turbulence and enables cold water entry from the lower part of the
tank.
(7) Boiler
2.2 EXTERNAL BODY
Thermosiphon external body is manufactured from sheet with cataphoresis electrostatic paint.
2.3 INSULATION
Pressurized polyurethane foam is filled between the boiler and the external body with the most
suitable density for heat insulation.
2.4 RESISTANCE
The external part of the resistance is manufactured of stainless steel, and the inner part is made of
resistance wire and magnesium oxide. Resistance flange contains the resistance, thermocouple pipe
and anode rod mounting bracket. It can be in different shapes and strengths according to model. The
mechanical thermostat, electronic thermostat and limit thermostat thermocouples attached into the
thermocouple pipe must be fitted to the deepest part of the pipe and a rubber cap should be fitted to
the end to prevent them from falling out.
Resistance
2.5 FLANGE GASKET
The leak proofness and electrical insulation between tank flange and the heating element flange is
achieved by a gasket. Gasket must be replaced in situations where the flange is removed, i.e. after
cleaning the boiler scale of the thermostat.
2.6 THERMOSTAT
Mechanical thermostat is used to adjust the water temperature at the desired level. Thermostat is
mounted on the front indicator panel. The capillary tube thermocouple is placed into the steel pipe on
the resistance flange so that the thermostat can sense the water temperature. Thermocouple must be
placed into the steel tube so that it will touch the deep end. The indicator lights red while the water is
heated to the temperature that the thermostat is set. Indicator lights green when the water reaches the
desired temperature.
FLANGE GASKET
FLANGE

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Thermostat.
2.7 ELECTRONIC THERMOSTAT
In electronically controlled thermostats, the temperature control and certain safety functions are
conducted by circuit board. Circuit board is found on the front panel. It contains two touch-buttons to
adjust temperature and one on-off touch button. Screen contains temperature value, resistance active,
hot water ready, freezing prevention and bacteria prevention indicator LEDs. After removing the
service cover, the electronic thermostat is removed by removing the crews on both sides inside the
indicator panel. The protective lexan film on the front part of the indicator must be replaced when
deformed.
The water temperature is set to the desired value by the circuit board. Setting is made only by using
the up-down temperature buttons. At the end of the operation, current water temperature in the
thermosiphon is displayed. And the resistance active lamp on the left side turns on. Hot water ready
indicator lamp turns on when water reaches the desired temperature.
Electronic thermostat.
A-MECHANICAL
CONTROL
Temperature Adjustment
Knob
On-Off Signal Lamp
B-ELECTRONIC CONTROL
(2) Hot water ready lamp
(1) On-Off Button
(6) Freezing Safety Lamp
(4) Upper Temperature Set
Button
Resistance Active Lamp
(5) Lower Temperature Set
Buton
(7) Bacteria Prevention Lamp

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Electronic Thermostat Error Codes:
In some error cases, the following codes are displayed on the circuit board indicator.
E1
Thermistor error
Check the thermistor socket. Replace the
thermistor with a new one.
E2
Low voltage warning
When voltage returns to normal, this error
will automatically be removed.
E3
Waterless operation
Error shall be removed when the boiler is
filled with water and power is cut off and
then turned on again.
2.8 LIMIT THERMOSTAT
In case water temperature in boiler over-increases or temperature setting thermostat fails, limit
thermostat maintains safety by deactivating resistance. When the limit thermostat is blown, first the
thermostat is checked for integrity. After the problem is removed, the limit thermostat is activated
again by pressing the reset button on it.
Limit thermostat.
2.9 SAFETY VALVE
Safety valve checks the water pressure in the tank. It provides protection against high pressure and
activates when the internal pressure exceeds 9 bars. Valve is closed in order to prevent the thermostat
from emptying when the water feed is cut off. The minimum pressure for the valve to open and allow
water in is 0.2 bars, which corresponds to 2 meters of water height. Safety valve has a latch that
opens the valve. This latch can be used to discharge the water tank.
Safety valve is inserted to cold water inlet of the thermosiphon.When mounting and using safety valve,
the following conditions should be followed.
1-As water may spill from discharging end, this pipe is required to be opened to atmosphere.To avoid
dripping water from damaging the surroundings, you can connect a drain hose to waste water drain.
2- To avoid lime accumulation and verify that it is not blocked, it should be operated by pressing the
latch in intervals.
3- When connecting safety valve to device, notice that discharging end is downwards.
Safety valve with drainage latch.
2.10 ANODE ROD
Corrosion is a chemical process that occurs between the metal of the thermosiphon (tank, pipes,
resistances) and the water around them. Corrosion causes opening of holes in the tank, decreases the

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mechanical strength of the components and causes the heating component to be damaged. The
reasons for corrosion are as below:
1. Melt oxygen (example: From 5 mg/l in high temperature to 12 mg/l in low temperature)
2. Salts that harden the water.
Magnesium anode is used to prevent the tank from being perforated.
Corrosion develops in three stages:
1. Oxygen that melts in water contacts the interior surface of the tank.
2. The iron of the tank starts to dissolve (atom loses two electrons and becomes Fe++ ion).
3. Iron ion is separated from the tank surface and bonds with oxygen to form (FeO). In this case, a
hole starts to form on the tank.
Both iron and magnesium are soluble in water; magnesium becomes the solution because it is more
electropositive (turns into Mg++ easier) compared to iron.
At this point, magnesium leaves the anode and bonds with oxygen atoms. Corrosion ends, in other
words magnesium rod corrodes as the thermostat remains the same.
The life of anode depends on the water temperature, its amount and quality. Anode must be checked
and replaced before it is completely out of use. Recommended duration is checking once every two
years.
Anode rod
Magnesium atom
(element that forms the anode)
Magnesium oxide
MgO

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2.11 CONNECTION SCHEMATICS
Mechanically controlled model Electronically controlled model
3. OPERATION PRINCIPLE
3.1 OPERATION
Tank is always filled with pressurized water. When the desired temperature is reached, control
thermostat shuts down the electric resistance. When hot water starts to be used, cold water starts to
enter the tank through the cold water Inlet pipe. Thermostat cools and reactivates the resistance. Cold
water is heated until it reaches the temperature value set in the thermostat. The water in the tank is
kept hot and ready for use until more water is drawn.
3.2 STRATIFICATION OF THE HOT AND COLD WATER LAYERS
The operating principle of a thermosiphon is the water forming layers with different temperatures
that don’t mix.
It is easy to explain this principle simply: when water heats, it expands and its density decreases
compared with cold water. In this case, the density decreases as water heats and it accumulates on
the top part of the tank. Water with lower temperature forms a layer closer to the lower part.
When hot water is drawn from the upper part of the tank, cold water enters the tank from below.
Thus, the density balance is achieved.
4. ELECTRICAL THERMOSIPHON PLUMBING
The usage life of a thermosiphon is largely dependent on its plumbing being done right. We
recommend that plumbing is conducted by a Professional. The plumber first has to check the water
source, power source and the waste water connections for conformity with manufacturer
recommendations.
The plumbing and commissioning of the thermosiphon should be conducted in accordance with the
instructions in the manual supplied with the device.

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4.1 MOUNTING AND PLUMBING OF THE UNIT
The following should be considered when mounting the thermosiphon to the wall.
•Thermosiphon must be in a location to meet the water connection point on the wall.
•The inserts and hanging screws attached to the wall must be strong enough. An 80-liter
thermosiphon can exceed 100kgs with its own weight. As this weight shall entirely rest on
the hanger screws, the screws must be screwed strong enough not to come off the wall.
•After hanging, the thermosiphon is adjusted to be parallel to the wall by the adjustment
plastic on the lower side.
•The device must not have any damage that will adversely affect electrical insulation.
•The power feed cable of device must be connected to the circuit breaker provided with the
device.
•Safety valve must definitely be mounted on the cold water inlet pipe with the blue ring.
•There are flexible gaskets on the fittings of the water connection hoses. Water tightness is
achieved without tightening the fittings too much. Fittings and gaskets might be damaged in
case to too much tightening. In case the hose lengths are not enough, only hoses of different
length recommended by Vestel Service Centre must be used.
•Thermosiphon must be mounted on a location where the water inside won’t freeze.
5. MAINTENANCE
5.1. RESISTANCE CORROSION BY THE TANK
Boiler scale (calcification) can cause the following operation problems:
•Decrease in usable hot water volume
•Increase in resistance malfunction risk
•Thermosiphon making noise during heating
•Thermostat activating and deactivating frequently
Thus, thermosiphon must be cleaned in a frequency depending on the water quality and product use.
The recommended cleaning period is at least once every two years.
The operation:
1. Cut the power off before cleaning the thermosiphon.
2. Shut the valve to cut off the water into the device.
3. Open the hot water faucet to remove the pressure in the tank and then close it.
4. Cut off the water main connections of the inlet pipe.
5. Remove the safety valve and attach a rubber hose of appropriate length for discharge instead.
6. Open the hot water faucet to drain the remaining water inside the thermosiphon.
7. Remove the screws that fix the flange (that the resistance is connected to).

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8. Remove the flange.
9. Clean the boiler scale carefully with hand or with a tool (depending on the device type).
5.2 Resistance Check
Wire Integrity Test
•Set the test device to OHM reading.
•Connect the two cables of the test device to the two terminals of the resistance.
•Test device should read the resistance (ohm) value of the resistance; if it does not give any
reading, resistance is disabled.

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Short Circuit Test
•Connect one cable of the test device to the resistance terminal. The other cable must be in
contact with the tooth part of the heating component.
•No resistance value must be read on the test device. Otherwise, the resistance must be
replaced.
5.2 Malfunction chart
MALFUNCTION
REASON OF
MALFUNCTION
REMOVAL OF
MALFUNCTION
No hot water can be
drawn.
(Only cold water)
* Power feed might be cut off.
*Thermostat might not be
running.
* Thermostat sensor might not
be placed correctly on the
heating component.
* Limit thermostat might be
cutting off the circuit.
* The V-automate at the feed
input might not be open.
* Resistance might not be active
or there might be a short circuit.
* There might be an open
circuit in resistance feed cables.
*Ensure power to the
thermosiphon.
* Set the thermostat temperature
adjustments correctly.
* Remove and reattach the
thermostat sensor.
* Press the limit thermostat reset
button and bring it to active
position.
* Bring the V-automate at the feed
input to turned on position.
* Replace the resistance and
gaskets.
* Check the current consistency in
power feed cables, sockets and
connection terminals.
Insufficient hot water
production.
* Hot/cold water pipe
connection might be clogged.
* Connections might be wrong.
* Connect the pipes correctly.
* Ensure the plumbing is in
accordance with the schematics.
Excessive hot water or
steam generation.
* Thermostat setting might be
incorrect or might be stuck.
* There might be calcification
or mud forming in the tank.
* Set the thermostat correctly or
replace the thermostat.
* Clean the scale or mud.
It takes too long for the
thermostat to reactivate.
* The tank connection of the
thermostat might not be correct.
* Thermostat might have lost its
accuracy.
* Place the thermostat sensor
correctly.
* Replace the thermostat with a
new one.
Heating time is long,
energy consumption is too
much and thermosiphon
cannot
reach maximum
* Hot water system might be
leaking.
* Resistance might be damaged.
* Locate and mend the leak.
* Replace the resistance.

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temperature.
MALFUNCTION
REASON OF
MALFUNCTION
REMOVAL OF
MALFUNCTION
The water coming from the
thermosiphon has a stench.
* Bacteria might have formed
in the thermosiphon due ton
on-continuous operation.
* Completely drain the water in
the thermosiphon and clean.
Thermosiphon activates and
deactivates frequently.
*Thermostat might be
malfunctioning.
* Resistance might be
covered with scale.
* There might be incorrect
power input.
* Replace the thermostat.
* Clean the resistance.
* Check the main voltage.
Thermosiphon makes noise
during heating.
* There might be calcification
on the resistance.
* It might be the sound of the
water boiling during the
resistance heating.
* Clean the resistance.
* It is a normal process. No action
is required.
Thermosiphon frequently
leaks water from the safety
valve during heating.
The water volume increases
due top heating and valve
activates when the pressure in
the tank exceeds 9 bars as a
result.
Make the drainage connection of
the safety valve. If that is not
possible, recommend placing an
expansion tank (with 5 litres
capacity) to the system.
Take care not to locate pressure
reducers or check valves close to
the thermosiphon. Cut off about 5
cm portion of the hot water pipe.
There is leakage in the
resistance and flange unit.
* Flange or resistance gaskets
might be damaged.
* Flange might be punctured
due to corrosion.
* Replace the gaskets.
* Replace the flange and the
gaskets (in both cases, mount the
flange carefully).
NOTE: In some models of the thermosiphons, heat control is performed electronically. Thus, the
thermostat used in temperature control is digital. It senses heat through a sensor.