DeDietrich DIETRISOL TRIO DT 250 User manual

TRIO DT 250 - TRIO DT 350
Solar domestic hot water tanks
DIETRISOL
User Guide
300028005-001-04
EN

2TRIO DT 250 - TRIO DT 350 16/07/2015 - 300028005-001-04
Contents
1 Safety instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.1 General safety instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.2 Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.3 Liabilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.3.1 Manufacturer's liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.3.2 Installer's liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2 About this manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2.1 Symbols used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2.1.1 Symbols used in the manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
3 Technical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3.1 Homologations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3.1.1 Certifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3.1.2 Directives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3.2 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3.3 Main parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
4 Setting the DHW calorifier outlet temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
4.1 Programming and setting the electrical back-up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
4.2 Setting the thermostatic mixing valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
5 solar regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
5.1 General description of how the unit operates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
5.2 Start-up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
5.3 Adjustment keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
5.4 Measured values and adjustment parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
5.4 Measured values and adjustment parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
6 Checking and maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.1 Solar installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.2 Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.2.1 Magnesium anodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.2.2 Safety valve or safety unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.2.3 Descaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.2.4 Casing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.2.5 Vent device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6.3 Solar circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Warranty certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
7 Appendix - Information on the Ecodesign and Energy Labelling Directives. . . . . . . . . . . . . . . . . . . . . . . .20

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1 Safety instructions
1.1 General safety instructions
Danger
This appliance can be used by children aged
from 8 years and above and persons with
reduced physical, sensory or mental capabilities
or lack of experience and knowledge if they have
been given supervision or instruction
concerning use of the appliance in a safe way
and understand the hazards involved. Children
shall not play with the appliance. Cleaning and
user maintenance shall not be made by children
without supervision.
Allowance must be made for a means of
disconnection in the fixed pipes in accordance
with the regulations on installations.
If a power cord is provided with the appliance
and it turns out to be damaged, it must be
replaced by the manufacturer, its after sales
service or persons with similar qualifications in
order to obviate any danger.
Draining the appliance:
`Turn off the domestic cold water inlet
`Open a hot water tap on the installation
`Open a safety unit valve
`When the water stops flowing, the appliance has
been drained
Respect the maximum water inlet pressure to
ensure correct operation of the appliance,
referring to the chapter "Technical
Specifications".
Any operation on the installation must be
performed by a qualified technician respecting
professional regulations and in accordance with
this document.
Before any work, switch off the mains supply to
the appliance. Protect the installation against
any unwanted restarts.
Solar installations must be earthed to protect
them against lightning.
Operation of the thermostatic mixing valve on
the solar hot water tank outlet must be checked
on commissioning of the solar system.
Pressure limiter device:
`The pressure limiter device (safety valve or safety
unit) must be operated regularly in order to clear out
any limescale deposits and ensure that it is not
blocked
`The pressure limiter device must be connected to
a discharge pipe
`As water may flow from the discharge pipe, it must
be kept open to the air, in a frost-free environment,
in a continuous downward gradient

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1.2 Recommendations
.Heating water and domestic water must not
come into contact with each other. The
circulation of drinking water must not be done in
the exchanger but only in the tank.
Insulate the pipes to reduce heat losses to a
minimum.
Only remove the casing for maintenance and repair
operations. Put the casing back in place after
maintenance and repair operations.
We recommend installing an EC175 package on the
collector sensor.
The installation must comply in all matters to the
standards and rules which govern the work and
interventions in individual and collective homes, and
other constructions.
France: DTU 65.12, NF P50-601, NF 12976-2.
Service the appliance regularly to ensure that it operates
correctly. Contact a qualified professional or take out a
maintenance contract for the annual servicing of the
appliance.
As the heat transporting fluid leaks much more easily than
water, carry out a visual check on the tightness of all
fittings and gaskets after a few hours' operation at normal
operating pressure.
To take advantage of the guarantee, no modifications
must be made to the appliance. The choice of
components for the solar system and their installation
must follow the instructions in this manual.
Never remove or cover labels and rating plates
affixed to the appliance. Labels and rating plates
must be legible throughout the entire lifetime of the
appliance. Immediately replace damaged or illegible
instruction or safety labels.
1.3 Liabilities
1.3.1 Manufacturer's liability
Our products are manufactured in compliance with the
requirements of the various applicable European
Directives. They are therefore delivered with 1marking
and all relevant documentation.
In the interest of customers, we are continuously
endeavouring to make improvements in product quality.
All the specifications stated in this document are therefore
subject to change without notice.
Our liability as the manufacturer may not be invoked in
the following cases:
`Failure to abide by the instructions on installing the
appliance
`Failure to abide by the instructions on using the
appliance
`Faulty or insufficient maintenance of the appliance
1.3.2 Installer's liability
The installer is responsible for the installation and
commissioning of the appliance. The installer is required
to observe the following instructions:
`Read and follow the instructions given in the
manuals provided with the appliance
`Install the appliance in acordance with the legislation
and standards currently in force
`Perform the initial start up and carry out any checks
necessary
`Explain the installation to the user
`If a maintenance is necessary, warn the user of the
obligation to check the appliance and maintain it in
good working order
`Give all the instruction manuals to the user

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2 About this manual
2.1 Symbols used
2.1.1 Symbols used in the manual
In these instructions, various markings and pictograms are used to
draw your attention to particular information. In so doing, De Dietrich
Thermique S.A.S wishes to safeguard the user's safety, obviate
hazards and guarantee correct operation of the appliance.
Danger
Risk of a dangerous situation causing serious physical
injury.
Warning
Risk of a dangerous situation causing slight physical
injury.
Caution
Risk of material damage.
Specific information.
ZReference
Refer to another manual or other pages in this instruction
manual.
`DHW: Domestic hot water.

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3 Technical specifications
3.1 Homologations
3.1.1 Certifications
NF certification
3.1.2 Directives
Compliance of design and manufacture
This product conforms to the requirements of european directive 97 /
23 / EC, article 3, paragraph 3, on pressure equipment.
Electrical compliance / Marking 1
This product complies to the requirements to the european directives
and following standards:
• 2006/95/EC Low Voltage Directive
Reference Standard: EN 60.335.1
Reference Standard: EN 60.335.2.21.
2004/108/EC Electromagnetic Compatibility Directive
Reference Standards: EN 50.081.1 / EN 50.082.1 / EN 55.014.

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3.2 Technical data
DIETRISOL
TRIO DT 250
DIETRISOL
TRIO DT 350
Maximum operating temperature
Solar exchangers °C 120 120
Boiler heat exchanger °C 90 90
tank °C 90 90
Maximum operating pressure Mpa (bar) 0.7 (7) 1 (10)
Maximum operating pressure in accordance with W/TPW (1) Mpa (bar) 0.6 (6) 0.6 (6)
Water content
Solar exchangers litres 9 8.1
Boiler heat exchanger litres 4.3 4.9
tank litres 250 350
Surface area
Upper solar heat exchanger m20.48 0.48
Lower solar heat exchanger m20.86 0.96
Boiler heat exchanger m20.64 0.72
Operation with boiler back-up
Top up volume litres 105 127
Solar volume litres 145 223
Power exchanged (2) (3) kW 21 23
Operation with electrical back-up
Top up volume litres 130 160
Solar volume litres 120 190
Output of the electrical back-up kW 2.4 3
Back-up volume heating time (from 15 to
60°C) h 2h50 2h50
Vecs 40 (5) (6)
Domestic hot water storage temperature:
55 °C
litres 355 420
Vecs40 (5) (6)
Domestic hot water storage temperature:
60 °C
litres 385 450
Continuous output ∆T = 35 K (2) (3) l/h 515 565
Flow rate for 10 minutes where ∆T = 30 K (on make-up
volume) (2) (4) l/10 mm 190 230
Maintenance consumption kWh/24h 2.2 2.7
Cooling constant Cr Wh/lKj 0.22 0.19
(1) Swiss Directives
(2) Domestic cold water input at 10°C - Primary inlet temperature at 80 °C
Values measured with a wall-mounted boiler
(3) Domestic hot water temperature: 45 °C
(4) Domestic hot water temperature: 40 °C
(5) Domestic cold water inlet 15 °C
(6) Values measured only on the back-up volume
Domestic hot water load setting: 60 °C

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3.3 Main parts
Dietrisol TRIO DT is a high performance solar DHW tank/calorifier
designed to be connected to Dietrisol NEO or POWER solar
collectors and an De Dietrich central heating boiler.
It is designed in such a way as to be able to cope with a solar collector
surface area of up to 4.5 m2(DT 250) and 6.5 m2(DT 350) under the
conditions set out in the chapter "Hydraulic Connection Primary Solar
Circuit".
tank
The high quality steel tank is lined with food standard quality
vitrified enamel, which protects it from corrosion and preserves
all the qualities of the domestic water.
The Dietrisol TRIO DT tank is fitted with 2 heat exchangers per
zone for solar heating and one heat exchanger for
supplementary heating by means of a fuel oil or gas boiler.
Protection against corrosion
The tank is also protected from corrosion by two magnesium
anodes which must be inspected every 2 years and replaced if
necessary.
Heat exchanger
The thermal exchanger welded into the tank is made of smooth
piping, the inside of which, which is in contact with the domestic
water, is enamelled.
Insulation
The tank is strongly insulated with high strength rigid
polyurethane foam with no chlorofluorocarbons (CFC), 50 mm
thick to minimise heat loss.
Casing
The outside casing is made of painted steel sheeting.
The top and side covers are made of ABS.
Solar station
The solar heating pump unit comprises the solar circuit safety
unit, a pressure and temperature gauge and a flowmeter to
visualise circulation of the solar fluid between the collectors and
the DHW tank. An expansion vessel is connected to the solar
unit; it is used to compensate for the expansion of the solar fluid
in which the temperature varies between 0 and 150°C.
Sol Plus TRIO regulator
The control system is the solar system's brain; it makes the solar
heating pump run at variable speeds according to the difference
in temperature between the bottom of the DHW tank and the
solar collectors. The control system manages the set point
temperature (temperature to be attained in the DHW tank),
overheating and nighttime cooling. The control system also
displays the various operating modes, the temperatures in the
collectors and in the bottom of the DHW tank, as well as
signalling any malfunctions.
1Pressure gauge - Primary solar circuit
2Safety control unit for the solar circuit (6 bar)
3Blue thermometer (tank solar heat exchangers outlet)
4Red thermometer (tank solar heat exchangers inlet)
5Primary solar circuit pump
6Manual bleed degasser
72-position 3-way directional valve
8Sol Plus TRIO regulator
98 l/6 bar expansion vessel, 2-bar pre-load
10 Automatic connection for expansion vessel
11 Primary solar circuit filling and draining device
12 Magnesium anode
13 Electric heating resistance
14 Magnesium anode

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4 Setting the DHW calorifier outlet temperature
4.1 Programming and setting the electrical back-up
The temperature of the volume of water heated by the electrical
resistor is set by the installer on commissioning of the installation
according to the size of the home.
Using the programming device installed in the electrical panel, it is
possible to adjust the volume of water heated to 40°C by the resistor
in two ways:
`By forcing contunuous heating by the resistor (off-peak hours
contact) for significant unforeseen needs.
`By programming the heating time outside off-peak periods (2
hours maximum according to the DHW volume at 40°C
required) to compensate for the lack of sunshine in winter, for
example. The programmed period outside off-peak hours must
preferably be between 12 h and 18 h.
4.2 Setting the thermostatic mixing valve
28. Domestic cold water inlet
57. DHW tank domestic hot water outlet
The mixing valve is set in the factory for a DHW outlet temperature of
60°C (position 6). To lower this temperature, remove the top cover
and turn the wheel anti-clockwise. In position 1, the outlet
temperature is lowered to 35°C.
C003732-A
57
28

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5 solar regulator
Always fitted to installation type 1 (Parameter ANL 1). ZSee next page (Start-up).
5.1 General description of how the unit operates
In automatic mode, the regulator operates in accordance with the
following principles:
`The sun's irradiation heat the transfer fluid in the collector. For
the regulation process to be triggered, a minimum temperature
of 30 °C is required in the collector and there must be a
temperature difference of 10 K by comparison with the tank.
`During the self-calibration phase that follows (adjustment
parameter tu, factory setting: 3 minutes), the solar pump (relay
1) operates at full speed (100 %).
`Subsequently, the solar pump regime is calculated dynamically
depending on a difference between the reference temperature
(parameter DT, factory setting 20 K) and the calorifier
temperature.
`When the zonal reversal temperature is reached in the
collectors (adjustment parameter SZ, factory setting 55°C), the
relay R2 switches the reversal valve to the upper zone in the
calorifier. The user therefore has immediate access to domestic
hot water at the set temperature.
`When the zonal reversal temperature is reached (adjustment
parameter SZ, factory setting 55°C), the set reference
temperature difference is lowered from 20 K to 10 K.
`Depending on the heat available, the system heats up the solar
tank and cuts off when the tank storage temperature is reached
(adjustment parameter SX, factory setting: 60 °C).
`When the temperature in the collectors reaches the maximum
value (adjustment parameter CX, factory setting 100°C), the
solar pump is triggered to cool the collectors. The pump
continues to operate until the temperature in the collectors is
lower than 5 K at parameter CX and/or the maximum storage
temperature (85°C) is reached in the hot water storage tank. As
soon as the temperature in the collectors drops below the
temperature in the calorifier, the calorifier is cooled down to its
set temperature. The installation is thus protected against
overheating and repeated stoppages, allowing thus the
prolonged absence of the user even in the summer period.
`The amount of heat transferred from the collectors to the tank
is displayed as parameter AH. The value is cumulative and is
constantly updated.
`The regulator (installation 2- ANL2 with heating back-up)
includes an additional function: A temperature sensor S3 is
located on the heating return.
- If the heating return temperature is equal to or greater than the
temperature of the solar tank, heating return is direct to the boiler.
- If the temperature in the solar tank is higher than the heating
return temperature, heating return passes via the solar tank. The
energy coming from the sun's rays or from a biomass boiler is thus
exploited to heat the home.
Installation 1
Installation 2
5.2 Start-up
%If the temperature in the solar collectors is higher
than 130°C, the control system operates in safety mode.
Wait until the evening before start-up or cool down (cover)
the solar collectors.

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Switch on the device. When initialisation is complete, the regulator
changes to automatic mode. The factory settings for this mode give
optimum performance with most installations.
The regulator is configured in the factory for installation type 1
(parameter ANL=1).
If special conditions make it necessary to change the settings, the
corresponding adjustment parameters can be reset.
Installation 1
Installation 2
5.3 Adjustment keys
The regulator is controlled by the 3 keys only located below the
display.
The down key is used to go to the next menu or to increase the
settings values.
The up key has the opposite effect.
The adjustment parameters are displayed after the measured values.
To access these parameters, hold down the down key for 2 sec. in
the TC parameter. When the display shows an adjustment
parameter, the word SET appears. To set the value displayed, press
the middle button SET.
1. Select the desired channel with the up and down keys.
2. Press the SET key: The word SET flashes.
3. Set the value with the up and down keys.
4. Press the SET key: The set value is stored. The word SET stops
flashing.
B000143-A

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5.4 Measured values and adjustment parameters
The regulator has a safety system that cuts off the tank at
temperatures of over 80°C.
Channel Abbreviation Range Increment Factory setting
Collector temperature TC [-50.0 ... 250.0] °C - -
Calorifier temperature TS [-50.0 ... 250.0] °C - -
Amount of heat kWh [0 ... 9999] kWh - -
Pump regime PC [0 ... 100] % - -
Self-calibration time tc [0 ... 5] minutes - -
Return temperature TR -50...250°C - -
Additional temperature TM -50...250°C - -
Type of installation ANL Installation 1
Installation 2 -Installation 1
Temperature difference enabling the passage of the heating
return via the solar tank DO [0.5 ... 19.5] K 0.1 6
Temperature difference enabling heating return directly to the
boiler DF [0.4 ... 19.5] K 0.1 4
Reference temperature difference DT [10 ... 20] K 0.1 20
Zone changeover temperature (tank) SZ [20 ... 80] °C 0.1 55
Set temperature of the solar calorifier SX [20 ... 80] °C 0.1 60
Maximum collector temperature CX [100 ... 125] °C 0.1 100 °C
Self-calibration phase tu [1 ... 5] minutes 1 3
Pump minimum speed PN [20 ... 100] % 130
Pump command mode POMP OnOF / PuLS / PSOL PSOL
Tubular solar collector function FT [0 ... 1] 1 0
Maximum flow rate Fx [0 … 20] l/min 0.1 Installation 1: 6.7
Installation 2: 4.2
Manual mode MM [0 ... 4] 1 4
Software version VN -- 2.00
Measured values
Adjustment parameter

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Measured value TC - Collector temperature
The value TC shows the temperature in °C given by the collector
sensor in real time.
Measured value TS - DHW sensor temperature
The value TS shows the temperature in °C given by the tank sensor
in real time
Measured value kWh - Amount of heat
The value kWh shows in kWh the total amount of heat produced by
the installation since the regulator was put into service.
The quantity of heat (kWh value) can only be used for checks
carried out for personal reasons.
Measured value tc - Self-calibration time
The value tc shows the self-calibration phase time remaining in
seconds. During the self-calibration phase, the pump operates at full
speed (100 %); its speed is only controlled after the self-calibration
phase.
Measured value TM - Additional temperature
An optional additional temperature sensor can be connected to
terminals 7 and 8. For example: Temperature in the top of the
calorifier.
Adjustment parameter ANL -Type of installation
The adjustment parameter ANL is used to select the following
installation configurations:
ANL 1 = Installation 1:
- Preparation of domestic hot water using a DIETRISOL TRIO
calorifier.
- Preparation of domestic hot water using a tank with 2 exchangers
connected to the solar circuit.
ANL 2 = Installation 2:
Solar installation for the preparation of domestic hot water with a DC
mixed calorifier and for heating back-up with temperature control on
the heating return circuit. The temperature control on the heating
return circuit prevents the boiler having to maintain the temperature
of the back-up volume in the calorifier in the event of prolonged
absence of sunshine.
Adjustment parameter DO - Temperature
difference enabling the passage of the heating
return via the solar tank
Adjustment range: 0.5 ... 19.5 K
Factory setting: 6 K
The parameter DO is used to set the temperature difference above
which heating return is directed via the 3-way valve to the solar tank.
Heating return thus passes via the solar tank if the solar tank
temperature is higher by at least 6°C than the heating return
temperature.
If the parameter ANL is set to 1 (installation 1), the parameter
DO is deactivated
Adjustment parameter DF - Temperature
difference enabling heating return directly to the
boiler
Adjustment range: 0.4 ... 19.5 K
Factory setting: 4 K
The parameter DF is used to set the temperature difference below
which heating return is directed from the 3-way valve directly to the
boiler. The solar energy stored in the solar tank is insufficient to
reheat the heating return. Heating return is thus directed directly to
the boiler if the solar tank temperature is lower by at least 4°C than
the heating return temperature.
If the parameter ANL is set to 1 (installation 1), the parameter
DF is deactivated

14 TRIO DT 250 - TRIO DT 350 16/07/2015 - 300028005-001-04
Adjustment parameter DT - Reference
temperature difference
Adjustment range: 10 ... 20 K
Factory setting: 20 K
Switching-on difference: Non-adjustable value 10 K
Switching-off difference: Non-adjustable value 5 K
The regulator reads the temperatures measured by sensors S1 (TC)
and S2 (TS) and compares the resulting temperature difference with
the switching-on difference which is preset to 10 K. Regulation is
activated when the temperature difference ∆T is equal to or greater
than the preset value. The display shows . When the value falls
below the preset 5 K switching-off difference, the regulator switches
off. The regulator tries to achieve a temperature difference of 20 K
(factory setting) between the collector and the tank to produce high
temperature hot water as rapidly as possible. To do this, it uses
dynamic speed control.
Adjustment parameter SZ - Zone changeover
temperature
Adjustment range: 20 ... 80 °C
Factory setting: 55 °C
If the temperature in the collectors reaches value SZ, the relay R2
closes.
If the temperature in the collectors is lower than value SZ, the arrow
"flashes.
If the temperature in the collectors is higher than value SZ, the arrow
#flashes.
We advise you to set the domestic hot water booster
temperature to 50°C. If the customer wants a higher
temperature, parameter SZ will have to be changed. SZ is
set to 55°C in the factory and must always be 5K higher
than the DHW booster circuit temperature setting(s).
If the domestic hot water boiler circuit is set at more than
50°C, SZ must be adjusted to 5K above this DHW circuit
temperature setting.
If the booster is electric, the resistance thermostat must be
set at 50°C.
Adjustment parameter SX - Set temperature of the
solar calorifier
Adjustment range: 20 ... 80 °C
Factory setting: 60 °C
Maximum tank temperature (emergency cut-off): Non-
adjustable value 85 °C
The set temperature Sx is the desired temperature for the solar
calorifier.
If the maximum tank temperature is exceeded, tank heating is
interrupted to prevent damage due to overheating. The display
shows and (flashing).
The higher the set temperature for the calorifier, the greater the
energy stored. Setting to 60 ... 75°C is suitable for normal use with
daily draw-offs.
In the event of prolonged absences (weekend, holidays):
- Reduce the calorifier temperature to 50°C
- Turn off the back-up (boiler or electrical resistance)
The installation is thus protected against overheating and the
longevity of the heat conducting fluid is conserved.

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16/07/2015 - 300028005-001-04 TRIO DT 250 - TRIO DT 350
Adjustment parameter CX - Maximum collector
temperature
Adjustment range: 100 ... 125 °C
Factory setting: 100 °C
Maximum collector temperature (overheating safety): Non-
adjustable value: 130 °C.
If the temperature in the collector rises above its maximum
temperature CX even though the solar circuit is stopped (tank set
storage temperature reached), the solar pump (R1) switches on and
cools the collector (system cooling). In these conditions, the tank
temperature rises, but it can't exceed 85 °C (safety cut-off).
If the calorifier reaches the maximum temperature of 80°C (safety
shutdown), the regulator switches off the solar pump.
The collectors may reach a temperature of 160 ... 200°C, which
is normal for a solar installation.
The cooling functions allows heat to dissipate; the system thus
remains operational longer during hot summers. When it leaves the
factory, the collector's maximum temperature is preset to 100 °C;
however, it is possible to change this within the range 100 ... 125 °C.
If the maximum collector temperature is exceeded, the display shows
, and (flashing).
Adjustment parameter tu - Self-calibration phase
Adjustment range: 1 ... 5 minutes
Factory setting: 3 minutes
When the solar collector reaches a minimum temperature of 30 °C
and a preset temperature difference of 10 K from the tank
temperature, the regulator switches on the solar circulating pump at
full speed for the time period set by parameter tu. During this phase,
any air bubbles present in the solar collectors or the pipes are moved
to the complete solar station by the high circulation speed in the pipes
and eliminated by the Airstop system (manual bleed degasser).
After this phase, the regulator changes to "matched flow" mode. The
remaining self-calibration time is displayed with parameter tc.
Adjustment parameter PN - Pump minimum
speed
Adjustment range: 20 ... 100%
Factory setting: 30%
Adjustment parameter PN sets a minimum value for the solar pump
speed at the relay R1 output. The lower the pump regime, the lower
its flow.
Adjustment parameter POMP - Pump command
mode
Adjustment range: OnOF / PuLS / PSOL
Factory setting: PSOL
The POMP parameter is used to select the correct command
program for the solar pump, according to the type of pump
used.PSOL control (default setting) is designed for PWM solar-
controlled heating pumps, PuLS control for conventional frequency-
modulation heating pumps and OnOF control for "ON/OFF heating
pumps.
Adjustment parameter FT - Tubular solar collector
function
Adjustment range: 0/1
Factory setting: 0
0: no
1: yes
If the regulator detects a temperature rise in the collector of 2 K
compared to the last measurement, the solar pump runs at full speed
for 30 seconds to measure the current average temperature.
The measured temperature thus becomes the new reference
temperature.
If the measured temperature (new reference) then increases again
by 2 K, the solar pump starts again for 30 seconds.
The regulator switches automatically to solar heating mode if the
temperature difference between the collector and the calorifer
exceeds the switching-on temperature difference when the solar
pump is operating or the system is stopped.
If the collector temperature falls by 2 K while the system is stopped,
the tubular solar collector activation temperature is rechecked.

16 TRIO DT 250 - TRIO DT 350 16/07/2015 - 300028005-001-04
Adjustment parameter Fx - Maximum flow rate
Adjustment range: 0 ... 20 l/min
Factory setting: Installation 1: 6.7 - Installation 2: 4.2
In order for the regulator to calculate the quantity of heat produced by
the installation (parameter kWh), input parameter Fx. The parameter
Fx is equal to the flow in litres per minute in the solar circuit.
Determine the value Fx using the following tables, according to the
configuration of the installation and the number or surface area of the
collectors. When the flow is input incorrectly, the display kWh will also
be incorrect.
The quantity of heat (kWh value) can only be used for checks
carried out for personal reasons.
`Flat solar collectors
`Tubular solar collectors
Adjustment parameter MM - Operating mode
Adjustment range: 0 ... 4
Factory setting: 4
For inspection and maintenance work, it is possible to operate the
regulator in manual mode. To operate the regulator in manual mode,
it is necessary to input parameter MM from the following table.
Solar panel
installation
Area
m2
Number of
panels
Flow rate
l/h
Flow rate
l/min
3 ... 5 1 or 2 400 6.7
6 ... 8 3 or 4 300 5
8 ... 10 4 or 5 250 4.1
8 ... 10 2x2 750 12.5
12 ... 15 2x3 670 11.2
16 ... 20 2x4 450 7.5
12 ... 15 3x2 850 14.2
18 ... 23 3x3 800 13.4
24 ... 30 3x4 650 10.9
16 ... 20 4x2 1200 20
24 ... 30 4x3 850 14.2
C000191
Number of panels Flow rate
l/h
Flow rate
l/min
minimum: 1x4 820 13.7
1x5 750 12.5
1x6 680 11.4
1x7 610 10.2
1x8 540 9
1x9 470 7.8
1x10 250 4.1
2x3 1400 20
2x4 1250 20
2x5 1100 18.4
2x6 950 15.9
2x7 750 12.5
2x8 600 10
2x9 540 9
2x10 400 6.7
MM1 R1 R2
0Open Open
1Closed Open
2Open Closed
3Closed Closed
4 automatic automatic

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6 Checking and maintenance
6.1 Solar installation
We recommend that you take out a preventive maintenance contract
to check the fluid level, antifreeze protection, pressure in the system,
leak test and general operation every year or every two years.
6.2 Tank
6.2.1 Magnesium anodes
The magnesium anode must be checked by a qualified professional
at least every 2 years.
6.2.2 Safety valve or safety unit
Have the condition of the anode checked after the first year. The
magnesium anode must be checked by a qualified professional at
least every 2 years.
6.2.3 Descaling
In hard water regions, it is advisable to ask the fitter to descale the
DHW tank exchanger once a year in order to maintain its level of
performance.
6.2.4 Casing
The casing of the DHW tank can be cleaned with soapy water.
6.2.5 Vent device
If the vent device is not used, the installer must check the seal on the
top vent connection.
6.3 Solar circuit
To check operation of the solar system, consult the display on the
control system.
The pressure in the solar circuit can be checked on the solar station's
pressure gauge. If the pressure shown is lower than 0.5 bar, call the
installer.
Never carry out work on the solar circuit yourself. Never
work on the safety valve yourself.

18 TRIO DT 250 - TRIO DT 350 16/07/2015 - 300028005-001-04
Warranty
You have just purchased one of our appliances and we thank you
for the trust you have placed in our products. Please note that your
appliance will provide good service for a longer period of time if it is
regularly checked and maintained. Your fitter and our customer
support network are at your disposal at all times.
Warranty terms
Starting from the purchase date shown on the original fitter's
invoice, your appliance has a contractual guarantee against any
manufacturing defect.
The length of the guarantee is mentioned in the price catalogue.
The manufacturer is not liable for any improper use of the appliance
or failure to maintain or install the unit correctly (the user shall take
care to ensure that the system is installed by a qualified fitter). In
particular, the manufacturer shall not be held responsible for any
damage, loss or injury caused by installations which do not comply
with the following:
- applicable local laws and regulations
- specific requirements relating to the installation, such as national
and/or local regulations
- the manufacturer's instructions, in particular those relating to the
regular maintenance of the unit
- the rules of the profession
The warranty is limited to the exchange or repair of such parts as
have been recognised to be faulty by our technical department and
does not cover labour, travel and carriage costs. The warranty shall
not apply to the replacement or repair of parts damaged by normal
wear and tear, negligence, repairs by unqualified parties, faulty or
insufficient monitoring and maintenance, faulty power supply or the
use of unsuitable fuel. Sub-assemblies such as motors, pumps,
electric valves etc. are guaranteed only if they have never been
dismantled.
France
The preceding dispositions are not exclusive of benefits for the
purchaser of the legal guarantee as stated in Civil Code articles
1641 to 1648.
Poland
Warranty conditions are included in the warranty card.
Switzerland
The application of the warranty is subject to the terms and
conditions of sale, delivery and warranty of the company marketing
our products.
Belgium
The preceding dispositions about the contractual guarantee are not
exclusive of profit if the need arises for the purchaser in Belgium of
the applicable legal dispositions on hidden defects.
Italy
The duration of our warranty is shown on the certificate delivered
with the appliance.
Our liability as manufacturer may not be invoked in respect of
incorrect use of the appliance, incorrect or insufficient maintenance
thereof, or incorrect installation of the appliance (you must
therefore ensure that installation and maintenance operations are
carried out respectively by a qualified professional and by an after
sales service company).
The legislation laid down by European Directive 99/44/EEC,
transposed by Legislative Decree No. 24 of 2 February 2002
published in O.J. No. 57 of 8 March 2002, continues to apply.
Russia
The foregoing provisions in no way affect the rights of the
consumer, which are guaranteed by the legislation of the Russian
Federation as regards hidden defects.
The terms and conditions of warranty and the terms and conditions
of application of the warranty are indicated on the warranty form.
The warranty shall not apply as regards the replacement or repair
of wearing parts under normal use. Such parts include
thermocouples, injection nozzles, flame control and ignition
systems, fuses and gaskets.
Turkey
Due to the laws and regulations the product life for this product is
10 years. During that time the producer and/or the distributor has
to provide after sales services and spare parts.
Other countries
The above provisions do not restrict the benefit of the legal laws
regarding hidden defects applicable in the buyer's country.

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Warranty certificate
Date of purchase: .............................................................................
Name and address of the purchaser: ...............................................
..........................................................................................................
..........................................................................................................
..........................................................................................................
..........................................................................................................
..........................................................................................................
Tel.:...................................................................................................
Information on the appliance (to be found on the nameplate):
Model: ...............................................................................................
Serial number: ..................................................................................
Retailer's stamp:

en
Appendix
Information on the ecodesign and energy labelling directives