First DTC 200/2G User Manual

1

FIRŠT-ROTOTEHNIKA, s.p., Radegunda 54, SI-3330 Mozirje, Slovenija

tel. [phone], fax. [phone], e-mail: info@rst.si, http://www.rst.si

DTC 200/2G

Differential thermostat can be used for:

- Heating sanitary water with possibility to control
the burner.

- Cooling living space with blowing the cool out­side air into the living space

USER’S MANUAL

ID-0706-22-DTC200-2g-upo-ang

DEAR CUSTOMER

You have bought a DTC 200/2G differential thermostat, manufac­tured according to the latest quality and safety standards. It is
designed in compliance with strict criteria and requirements of
West European markets and enables efcient use of solar energy
which enables considerable savings of other sources for domestic
water heating. It was tested at TUV institute in München.
Our products are available in the markets for several years and
satisfy the needs of demanding customers from hot Greece to
north Germany.
We are convinced that the use of our product will satisfy your
needs too and help you to save your money.

Thanks for your condence !

GENERALLY:

With differential thermostat there are three possible ways of use:

1. HEATING THE DOMESTIC HOT WATER FROM ONE
HEATING SOURCE (SOLAR COLLECTORS, BOILERS, HEAT
PUMP...) WITH CONTROLLING THE HEATING SOURCE
(BURNER).

Differential thermostat controls the electric motor actuated ball
valve (EMV 110..) and the circulation pump. If it necessary, turns
ON or OFF the heating source (burner).

2. HEATING THE DOMESTIC HOT WATER FROM ONE
HEATING SOURCE (SOLAR COLLECTORS, BOILERS, HEAT
PUMP...) WITH ADDITIONAL HEATING WITH ELECTRICAL
HEATER.

Differential thermostat controls the electric motor actuated
ball valve (EMV 110..) and the circulation pump. In case that
the primary heating source (solar collectors, boilers...) has not
enough energy, water in water tank is heated with elec trical
heater.

3. COOLING LIVING SPACE WITH BLOWING THE COOL
OUT SIDE AIR INTO THE LIVING SPACE

Differential thermostat controls the ventilator.

FIRŠT

USER’S MANUAL

This manual is for user. It describes the operation of differ en tial
thermostat and it’s correct use. Before setting the pa ram eters be
sure in which way of use is used. Carefully read the in structions
to make good use of the product.

We reserve the right to modify the instructions and the technical
data of the product without prior notice.

2

DTC 200/2G

FIRŠT-ROTOTEHNIKA, s.p., Radegunda 54, SI-3330 Mozirje, Slovenija

tel. [phone], fax. [phone], e-mail: info@rst.si, http://www.rst.si

FIRŠT-ROTOTEHNIKA, s.p., Radegunda 54, SI-3330 Mozirje, Slovenija

tel. [phone], fax. [phone], e-mail: info@rst.si, http://www.rst.si

CONTROL PANEL:

LEGEND:

1. Selector switch for choosing the operation

2. Knob for setting temperature in DHWT (domestic hot water
tank)

3. Knob for setting temperature difference of heating source
(collectors, boiler, ...) and in user (hot water tank).

4. LED indicator for burner operation.

5. LED indicator for pump operation.

1st WAY OF USE

HEATING THE DOMESTIC HOT WATER FROM ONE HEATING
SOURCE (SOLAR COLLECTORS, BOILERS, HEAT PUMP...)
WITH CONTROLLING THE HEATING SOURCE (BURNER).

OPERATION

DTC 200/2G single differential thermostat measures the tem­pera ture of heating source (collectors, boiler, ...) and in user
(hot water tank).
Heating effect is provided, when heating source temperature
is higher than the temperature of the user (water in hot water
tank). Consequently minimum difference should be 3K-5K. Rec­ommendable minimal value is 5K.
When the temperature of the source exceeds the temperature
around the user for pre-set difference opens the electric motor
actuated ball valve and switches the pump.
The thermostat switches off the pump if pre-set temperature is
reached in hot water tank (ad justable from 5° to 85°C).
If it’s need for heating the hot water tank and the temperature of
heating source (boiler) is to low, then thermostat switch on the
burner of the boiler and when the conditions of the difference is
assured, pump is switch on.
The burner is always on, when the heating is needed.

Use of selector switch:

With selector switch (1) you select one of the following modes

of operation:

OFF Irrespective of temperature values
the pump is off.

AUTO Automatic operation of thermostat

(normal operation)

ON 1 Irrespective of temperature values the pump is on. This
mode is designed for testing purposes, servicing and
in case of troubles.

ON 1+2 Irrespective of temperature values the pump and
burner are on. This mode is designed for testing
purposes, servicing and in case of troubles.

Mode OFF doesn’t enable galvanic separation from
mains. When replacing the pump, disconnect supply
voltage!

TEMPERATURE SETTING OF HOT WATER TANK

With knob (2) you can set max. temperature in
water tank between 5°C and 85°C.
When the temperature is reached, thermostat
deactivates pump and close motorised ball valve
regardless the temperature of heating source.
If hot water is used by the appliance with
limited max. temperature of inflow, this

setting is very useful.

DIFFERENCE SETTING

With knob (3) you can set temper ature
difference of heating source (collectors,
boiler, ...) and in user (hot wate r tank)
between 0K and 15K.
Heating effect is provided, when heating source
temperature is higher than the temperature of
the user (water in hot water tank). Consequently
minimum difference should be 3K-5K.
The difference is set in relation to the volume of heat losses of
the system which depend on lengths of pipes from source to the
water tank and on pipeline insulation.

CONTROL PANEL:

2nd WAY OF USE

HEATING THE DOMESTIC HOT WATER FROM ONE HEATING
SOURCE (SOLAR COLLECTORS, BOILERS, HEAT PUMP...)
WITH ADDITIONAL HEATING WITH ELECTRICAL HEATER.

Differential thermostat controls the electric motor actuated
ball valve (EMV 110..) and the circulation pump. In case that
the primary heating source (solar collectors, boilers...) has not
enough energy, water in water tank is heated with electrical
heater.

OPERATION:

DTC 200/2G single differential thermostat measures the
temperature of heating source (collectors, boiler, ...) and in user
(hot water tank).

Heating effect is provided, when heating source temperature
is higher than the temperature of the user (water in hot water
tank). Consequently minimum difference should be 3K-5K.
Recommendable minimal value is 5K.

When the temperature of the source exceeds the temperature
around the user for pre-set difference opens the electric motor
actuated ball valve and switches the pump.

The thermostat switches off the pump if pre-set temperature is
reached in hot water tank (adjustable from 5° to 85°C).

If it’s need for heating the hot water tank and the temperature
of heating source (boiler, collector) is to low, then thermostat
switch on electrical heater. Electrical heater heats water to desire

temperature.

Electrical heater is active, when the primary heating source is
inactive - they never work at same time. Priority has main heating
source (collector, boiler, ...).

FIRŠT-ROTOTEHNIKA, s.p., Radegunda 54, SI-3330 Mozirje, Slovenija

tel. [phone], fax. [phone], e-mail: info@rst.si, http://www.rst.si

3

DTC 200/2G

FIRŠT-ROTOTEHNIKA, s.p., Radegunda 54, SI-3330 Mozirje, Slovenija

tel. [phone], fax. [phone], e-mail: info@rst.si, http://www.rst.si

LEGEND:

1. Selector switch for choosing the operation

2. Knob for setting temperature in DHWT (domestic hot water
tank)

3. Knob for setting temperature difference of heating source
(collectors, boiler, ...) and in user (hot water tank).

4. LED indicator for need for heating water in DHW tank. It
doesn’t show working of el. heater.

5. LED indicator for pump operation.

Use of selector switch:

With selector switch (1) you select one of the following modes

of operation:

OFF Irrespective of temperature values the

pump and burner are off.

AUTO Automatic operation of thermostat

(normal operation)

ON 1 Irrespective of temperature values the pump is on. This
mode is designed for testing purposes, servicing and in case
of troubles.
ON 1+2 Irrespective of temperature values the pump and el.
heater are on. This mode is designed for testing purposes,
servicing and in case of troubles.

Mode OFF doesn’t enable galvanic separation from

mains. When replacing the pump, disconnect supply
voltage!

TEMPERATURE SETTING OF HOT WATER TANK

With knob (2) you can set max. temperature
in water tank between 5°C and 85°C.
When the temperature is reached, thermostat
deactivates pump and closes motorised ball
valve regardless the temperature of heating
source.
If hot water is used by the appliance with
limited max. temperature of inow, this setting is very useful.

DIFFERENCE SETTING

With knob (3) you can set temper ature
difference of heating source (collectors,
boiler, ...) and in user (hot wate r tank)
between 0K and 15K.
Heating effect is provided, when heating
sour ce tem pe rature is h igher than the
temperature of the user (water in hot water
tank). Consequently minimum difference
should be 3K-5K.
The difference is set in relation to the volume of heat losses of
the system which depend on lengths of pipes from source to the

3rd WAY OF USING

Cooling living space with blowing the cool outside air into
the living space

OPERATION

DTC 200/2G single differential thermostat measures the

temperature of outside air and inside air.

Cooling effect is provided, when cooling source temperature is
lower than the temperature of inside air. Consequently minimum
difference should be 2K.

When the temperature of outside air is below the temperature of
inside air it switches on the ventilator.

The thermostat switches off the ventilator if pre-set minimum
temperature is reached (adjustable from 5° to 85°C).

CONTROL PANEL:

LEGEND:

1. Selector switch for choosing the operation

2. Knob for setting minimal ambient temperature

3. Knob for setting temperature difference of cooling source
(outside air) and ambient.

4. LED indicator - not in function

5. LED indicator for ventilator operation.

Use of selector switch:

With selector switch (1) you select one of the following modes

of operation:

OFF Irrespective of temperature

values the ventilator is off.

AUTO Automatic operation of

thermostat (normal operation)

ON 1 Irrespective of temperature values the
ventilator is on. This mode is designed for testing purposes,
servicing and in case of troubles.
ON 1+2 Irrespective of temperature values the ventilator is
on. This mode is designed for testing purposes, servicing and
in case of troubles.

Mode OFF doesn’t enable galvanic separation from

mains. When replacing the pump, disconnect supply
voltage!

MINIMAL TEMPERATURE SETTING OF AMBIENT

With knob (2) you can set min. temperature in
ambient 5°C and 85°C.
When the ambient temperature is reached,
thermostat deactivates ventilator regardless the
temperature of cooling source (outside air).

DIFFERENCE SETTING

With kno b (3) y ou c an set temperature
difference of cooling source (outside air) and
in ambient between 0K and 15K.
Cooling effect is provided, when cooling source
temperature is lower than the temperature of
inside air. Consequently minimum difference
should be 2K.

4

DTC 200/2G

FIRŠT-ROTOTEHNIKA, s.p., Radegunda 54, SI-3330 Mozirje, Slovenija

tel. [phone], fax. [phone], e-mail: info@rst.si, http://www.rst.si

Trouble shooting guide

In solar heating systems motor actuated ball valves can prevent
various inconveniences.
o Effectively prevent hydraulic shocks in systems as they require
30 seconds for complete opening.
o Due to their shape they do not impede the ow.
o Springs are not included, therefore noise does not appear.
o When closed, 100% sealing is guaranteed.
o They have an output for pump up to 100 W in open position,
therefore they do not present a hydraulic load for pump in
closed position. They enable pump switching on only in
completely open position.
o Due to installed RELAY module they enable control with make
contact only.
o If during closing or opening process impurities enter in valve,
which could block it, the valve stops and immediately afterwards
continues with opening or closing process in opposite direction,
so that water ow can rinse the impurities up to cleaning net
(anti-blocking system).
o Possibility of manual control. This function relieves airing the
system or lling the system with water.
o It prevents coaxial cooling of DHWT by one pipe in night-time.

For preventing coaxial
cooling in night-time it
is necessary to build in
motorised ball valve EMV

110... in heating pipe of
DHW tank exchanger.

In night-time the temperature of water in DHWT
is usually higher than in collector. In this case it is
possible coaxial cooling of the DHWT through one
pipe. If the pipe has enough diameters and it is
straight and vertical, then water circulation begins
in just one pipe. In the middle, water goes upwards,
and at the edges downwards.

One solution for this is to build in nonreturn valve.
But with its use is increased the load of pump, the
ow reduced, and the ventilation of the system
hindered.

All these problems are solved by the motorised ball
valve series EMV 110 ...

HOT WATER

COLD WATER

EMV 110 602/4230

EMV 110 502/7930

EMV 110 316/89I0

Advantages of motor actuated ball valves of EMV110..series with incorporated relay
module for solar heating systems

TROUBLE POSSIBLE FAILURE REMEDY

The pump is not operating irrespective

of temperature

- Power supply is not connected

- Selector switch is in position OFF

- DHWT sensor T2 is disconnected

- Collector sensor T1 is short circuited

- Check power supply

- Set the selector switch in position AUTO

- Check sensor

- Check sensor

The pump operating permanently
irrespective of temperature

- Selector switch is in position ON1

- Collector sensor T1 is disconnected

- DHWT sensor T2 is short circuited

- Set the selector switch in position AUTO

- Check sensor

-Check sensor

The pump and burner operating
p e r m an e n t l y i r r e sp e c t i v e o f

temperature

- Selector switch is in position ON1+2

- Collector sensor T1 is disconnected

- DHWT sensor T2 is short circuited

- Set the selector switch in position AUTO

- Check sensor

- Check sensor

Temperature regulation of DHW tank

is not working

- Motorised ball valve is permanently open
or nonreturn valve is open (thermosiohon
water circulation is enabled)

Check the installation

In spite of enough collector’s energy
the water temperature in DHWT is not
high enough – water is too cold

-Setting of DHWT temperature is too low

-The difference setting is set to high

-Check settings

The temperature is reached, but the
heating/cooling is still running

- Jumpers are not set correctly - Check jumper’s settings

In AUTO position nothing happens - Jumpers are pulled out - Set jumpers in suitable position