OSO TERMO PLUS-E User manual

TERMO ELECTRIC BOILERS
MANUAL
OSO TERMO RS -E
OSO TERMO PLUS - E
OSO TERMO PTV – E
B C

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Contents
1. Introduction ....................................................................................................................... 1
1.1. Applicable documents................................................................................................. 1
1.2. Retention of documents .............................................................................................. 1
1. . Features and benefits ................................................................................................. 1
1.4. Termo concept............................................................................................................ 1
1.5. Outside temperature sensor........................................................................................ 1
1.6. Heating curves............................................................................................................ 1
1.7. Termo E Range........................................................................................................... 2
1.8. Water heater temperature sensor ............................................................................... 2
2. Termo E range .................................................................................................................. 1
2.1. Key to TERMO boilers ................................................................................................ 1
2.1.1. RS - E................................................................................................................... 1
2.1.2. Plus - E ....................................................................................................................
2.1. . PTV - E .................................................................................................................... 5
2.2. Expansion Vessel Characteristics (Plus And PTV Boilers) .......................................... 7
2. . Supply Characteristics 240V N ~ 50/60 Hz ................................................................. 7
. Installation......................................................................................................................... 8
.1. Content included in delivery ........................................................................................ 8
.2. Standards & Regulations ............................................................................................ 8
. . Physical installation..................................................................................................... 8
. .1. Select position for boiler ....................................................................................... 9
. .2. Fitting the boiler hanging bracket.......................................................................... 9
. . . Recommendations for handling ............................................................................ 9
. .4. Removing/fixing the front and top case................................................................10
.4. Plumbing & Heating installation & commissioning ......................................................10
.4.1. Installation ...........................................................................................................10
.4.2. Ancillary components ..........................................................................................10
.5. Connection to the electrical mains supply ..................................................................11
.6. Room thermostat, temperature probes and pumps connection ..................................12
.6.1. Connect room thermostat/programmer ................................................................12
.6.2. Fit external temperature sensor...........................................................................12
.6. . Fitting hot water cylinder temperature sensor (PTV-E only) .................................1
.6.4. Fitting pump connections and expansion vessel (RS – E only) ...............................1
4. Setting up Boilers .............................................................................................................14
4.1. Control Panel (including fault finding indicators).........................................................14
4.2. Choose type of heating (radiator or under floor heating) ............................................15
4.2.1. Hybrid Systems combining radiator and UFH ......................................................16
4. . Activating system and programming central heating ..................................................16
4. .1. Heating curves explained. ...................................................................................16
4. .2. To set correct curve.............................................................................................17
4. . . Setting internal temperature ................................................................................17
4. .4. Programmable room thermostats & setting variable internal temperatures ..........17
5.4. Domestic hot water priority.........................................................................................18
4.5. Protection from freezing .............................................................................................18
4.5.1. Domestic hot water..............................................................................................18
4.5.2. Central heating........................................................................................................18
5. Recommended annual checks (all boilers) .......................................................................19
6. Central heating controls advanced menu..........................................................................20

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6.1. Domestic hot water advanced menu (control panel type 2) ........................................22
7. Fault finding guide ............................................................................................................24
8. After Sales service information ......................................................................................... 0
9. Cascade power limiter ...................................................................................................... 0
10. OSO Hotwater UK Ltd .................................................................................................... 0
11. Appendices..................................................................................................................... 0
11.1. Appendix 1 - Termo RS with space heating and water heating ................................ 1
11.1.1. Schematic diagram Termo RS - E ..................................................................... 1
11.1.2. Wiring diagram Termo RS - E............................................................................ 1
11.1. . S-Plan wiring layout Termo RS -E ..................................................................... 2
11.2. Appendix 2 - Termo RS – Space heating only..........................................................
11.2.1. Schematic diagram Termo RS - E .....................................................................
11.2.2. Wiring diagram Termo RS-E..............................................................................
11.2. . S-Plan wiring layout Termo RS-E ...................................................................... 4
11. . Appendix - Termo PLUS E.................................................................................... 5
11. .1. Schematic diagram Termo plus-E...................................................................... 5
11. .2. Wiring diagram Termo plus-E ............................................................................ 5
11. . . S-Plan wiring layout........................................................................................... 6
11.4. Appendix 4 Termo PTV E ........................................................................................ 6
11.4.1. Schematic diagram Termo PTV-E ..................................................................... 6
11.4.2. Wiring diagram Termo PTV-E............................................................................ 6
11.4. . S- Plan wiring layout Termo PTV-E ................................................................... 7

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Page 1
Terminology used in this manual
The central heating boiler water circuit is called primary
The domestic hot water is called secondary (dhw)
1. Introdu tion
Thank you for purchasing the Oso Termo E electric central heating boiler.
To ensure a correct and safe installation and economical use, please read these instructions thoroughly before
installation.
1.1. Appli able do uments
The following additional documents are provided with the appliance:
For the owner of the system:
Instructions for use
Warranty card
For the qualified te hni ian:
Instructions for installation
Electrical drawing for the appliance
1.2. Retention of do uments
Please pass on this installation manual to the owner of the system. The owner should retain the manuals so that
they are available when required.
1.3. Features and benefits
The boiler provides wet system central heating by passing the primary water over the immersion heaters. The
immersion heaters are located on the under-side of boiler ensuring the elements are constantly immersed in the
heating medium (water with appropriate inhibitor). The primary temperature in the heating circuit is determined by
the outside temperature sensor and the heating curve selected in the boiler, (see sections 1.2, 1. and .5. ) The
boiler temperature probe will activate and modulate 1, 2 or elements in the boiler to achieve the desired primary
temperature. The boiler has an automatic pump overrun for both central and water heating that prevents a build
up of heat in the boiler. The boiler reservoir is insulated with 19 mm self-extinguishing Armaflex insulating
material, which is sufficient to direct the whole heat only to the heating system.
The boiler operates by rapidly heating a small water quantity. Energy use is maintained at 100% efficiency.
No flue or fan required - Almost silent in operation - No bulk oil storage tanks required
No annual safety check required
1.4. Termo on ept.
The OSO Termo E range of boilers uses technology widely used in Europe but relatively new in the UK, that
modulates the boiler to reduce power consumption.
1.5. Outside temperature sensor
An outside temperature sensor is supplied with the boiler to be fitted to an outside shaded wall. This sensor
informs the boiler of the outside temperature.
1.6. Heating urves
The boiler is pre-programmed with a number of heating curves to select from.
The boiler calculates the heat required in the property based on the outside temperature and the set heating
curve – the colder it is outside, the higher the primary temperature needed in the heating system.
Heating curves are set for a particular property and selection is dependent on the insulation levels of the property.
Modern, well insulated buildings have a different heating curve to a less well insulated building. A poorly insulated
house will require a higher primary heating temperature.
Heating curves also vary according to radiator or under-floor heating. The factory set heating curve is for a
building constructed to 2000 building regulations with radiator heating. Many boilers therefore will not require
adjustment of heating curve.
Changing the heating curves at the time of installation is a simple process for the installer. A table is shown on
page 20 indicating which heating curve is required for the building type. Once the heating curve is correctly set, it
should never require changing.
The heating curve will aim for the property to be heated to 22°C. Not all households wish for the same internal
temperature, if the residents of the property require a higher or lower temperature, the selected curve should be
offset up or down by the appropriate number of degrees. Full instructions are given on page 19.
A room thermostat (not supplied) must be installed to finely regulate internal temperatures.

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Page 2
1.7. Termo E Range
TERMO RS E is a boiler and software package only. Expansion vessel, pump and motorized valves are not
supplied
TERMO Plus E is a system boiler for central heating only. Expansion vessel & pump is supplied in the boiler.
TERMO PTV E is a system boiler for central heating and will provide heat for a domestic hot water cylinder. For
ease of reference the boilers will be referred to in this installation manual as RS E, Plus E and PTV E.
TERMO boilers are available in (240V single phase): 4.8, 6, 7.2, 10.8, and 14.4 kW. OSO Termo boilers can be
connected together to provide more power, the boilers can also be supplied for use on three phase supplies.
Please contact Oso for details.
1.8. Water heater temperature sensor
The Termo PTV E boiler is supplied with a temperature probe that is inserted between the cylinder wall and
insulation or in a dry pocket. This probe then relays cylinder temperature information back to the boiler. The boiler
will then produce sufficient heat to raise the temperature of the domestic water to the desired level.

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Page 1
2. Termo E range
2.1. Key to TERMO boilers
2.1.1. RS - E
1. Primary flow
2. Primary return
. External boiler jacket
4. Boiler
5. Armaflex Insulation
6. Immersion heaters
7. Control panel
8. Cable entry point
9. Contactors and RCD switch
10. Charge and discharge val ve
11. Pocket with temperature probe
12. Safety valve (supplied loose)
1 . Drain valve (not supplied)
14. Isolation valves (not supplied)
15 Manual venting valve (not
supplied)

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Page 2
RS – E
Te hni al Data For RS E
Power
kW
Boiler
Capa ity
Litres
Dimensions
mm
Dry
Weight
kg
Maximum
primary
operating
pressure
MPa (bar)
Conne tion
BSP male
Power supply
4.8
6
7.2
10.8
14.4
6
A 0
B 750
C 2 0
D 100
E 57
F 126
21.4 0,25 (2,5)
¾”
240V N ~ 50/60 Hz

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Page
2.1.2. Plus - E
1. Primary flow
2. Primary return
. External boiler jacket
4. Boiler
5. Armaflex insulation
6. Electrical heaters
7. Control panel
8. Cable entry point
9. Contactors
10. Expansion vessel
11. Circulation pump
12. Safety valve 2.5 bar
1 . Automatic air vent (AAV)
14. Charge and drain valve
15. Boiler venting valve
16. Air-indicator
17. Manifold
18. RCD switch
19. Pocket with temperature probe
20. Pressure probe

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Page 4
Plus – E
Te hni al Data For Plus E Boilers
Power
kW
Boiler
Capacity
Litres
Expansion
vessel
L/bar
Dimensions
Mm
Dry
Weight
kg
Maximum
primary
operating
pressure
MPa bar)
Connection
BSP male
Power supply
4.8
6
7.2
10.8
14.4
6 8 / 0,8
A 0
B 9 0
C 2 0
D 100
E 65
F 20
4.5 0,25 (2,5)
¾”
240V N ~ 50/60 Hz

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Page 5
2.1.3. PTV - E
1. Primary flow
2. Primary return
. External boiler jacket
4. Boiler
5. Armaflex insulation
6. Electrical heaters
7. Control panel
8. Cable entry point
9. Contactors
10. Expansion vessel
11. Circulation pump
12. Safety valve 2.5 bar
1 . Automatic air vent (AAV)
14. Charge and drain valve
15. Boiler venting valve
16. Air-indicator
17. Manifold
18. RCD switch
19. Pump for water cylinder
20. Primary flow for water cylinder
21. Pocket for temperature probes
22. Pressure probe

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Page 6
PTV- E
Te hni al Data For PTV- E Boilers
Power
kW
Boiler
Capacity
Litres
Expansion
vessel
L/bar
Dimensions
Mm
Dry
Weight
kg
Maximum
primary
operating
pressure
MPa bar)
Connection
BSP male
Power supply
4.8
6
7.2
10.8
14.4
10 10/0,8
A 400
B 9 0
C 2 0
D 150
E 65
F 150
G 50
H 05
44.2 0,25 (2,5)
¾”
cylinder
1”
(heating)
240V N ~ 50/60 Hz

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Page 7
2.2. Expansion Vessel Chara teristi s (Plus And PTV Boilers)
Volume of
Expansion
Vessel
L
Maximum
Expansion
Vessel
Pressure
MPa bar)
Filling
Pressure
MPa bar)
Maximum
Pressure
In heating
System
MPa bar)
Max Height
Difference
in central
Heating
System
m
Effective
capacity of
Expansion
Vessel
L
Adsorption
Capacity
%
Maximum
amount of
water in
primary
system
L
Maximum
power of
Boiler
kW
8 4.0 114 14.4
10
0.4 (4) 0.08
(0.8) 0. ( ) 10
5.0
50%
14 14.4
Values are related to working temperature range from 10C to 90C.
2.3. Supply Chara teristi s 240V N ~ 50/60 Hz
POWER nominal
urrent
MCB Rated short- ir uit
breaking apa ity
In (EN 60898)
Rated short- ir uit
breaking apa ity
In (IEC 947-2)
Cable size* RCD swit h type
4.8 kW 20 A B25-1 25-2/0.0 A
6 kW 25 A
x 4 mm2
7.2 kW 0 A
B 2-1
x 6 mm2
40-2/0.0 A
10.8 kW 45 A B50-1 6 -2/0,0 A or 40-4/0.0 A
14.4 kW 60 A B6 -1
10 kA 15 kA
x 10 mm2
80-2/0,0 A or 6 -4/0.0 A
*min. ondu tor's ross-se tion in mm
2
is based on maximum length of 20 m.

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Page 8
3. Installation
3.1. Content in luded in delivery
TERMO boilers are delivered
pre-assembled. Check that all
parts have been delivered
intact. For exact list of parts see
figure and table below. If parts
are damaged or missing,
please consult OSO Hotwater
UK Ltd.
Contents in luded within delivery
Item Quantity Des ription
1 1 TERMO boiler
2 1 Instructions and warranty card
1 (2) Hanging bracket
4 1 External temperature sensor
5 1 Water cylinder temperature sensor (standard for PTV - E, optional for RS- E)
6 1 Pressure relief valve (In case of Termo Plus and Termo PTV it is already fitted
on boiler, In case of Termo RS it is supplied loose)
3.2. Standards & Regulations
The OSO Termo range of boilers are BEAB approved and E marked.
Health and Safety at Work Act 1974 - When working with Termo boilers, ensure that protective clothing
and equipment is used appropriate to parts that may considered hazardous to health and safety.
ontrol of Substances Hazardous to Health ( OSHH 1988) - Glues, paints and sealants are used in the
manufacture of this product and present no known hazards when used in the manner for which they are
intended.
The guarantee is only valid if the following conditions are observed:
The boiler must be installed by a registered engineer to comply with current building regulations, current
IEE electrical wiring regulations (BS 7671), local authority regulations, water supply regulations and
health and safety at work regulations. Other Relevant British/European standards should be adhered to,
including;
BS 5449 - Specification for forced circulation hot water central heating for domestic premises,
BS 7593, treatment of water in domestic hot water central heating systems
Re ommended pressure of entral heating installation is 1.5 bar, maximum operating pressure is 2.5 bar.
3.3. Physi al installation
IMPORTANT – MOVING, POSITIONING AND INSTALLING THE BOILER EXCEEDS THE RECOMMENDED
WEIGHT FOR A ONE MAN LIFT.
The boiler must be handled and transported carefully and stored in a safe, dry place.
Plus - E, PTV - E and RS – E are designed for wall installation in an upright position. Fixed wall brackets are
provided on the back of the boiler. The boiler should be fixed in position on a suitable load-bearing wall prior to
pipe connection.
The boiler should be fitted in a dry place not subject to extremes of temperature. Cylinder cupboards and kitchens
are acceptable but bath or showers rooms are not.

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Page 9
3.3.1. Sele t position for boiler
The boiler should preferably be installed on the lowest point in relation to the installation. This ensures that
elements are always immersed in water and there is no danger of burning out.
When positioning the boiler, ensure there is
adequate surrounding space to allow for pipe
connection, ventilation, servicing and replacement
of components. Refer to the diagram below for
guidance.
Access is required to the control panel connections
at underside of the boiler and the power supply
connection, located at left bottom side of boiler.
Ensure that bottom part of boiler is accessible to
change the immersion element.
Ensure the boiler is in a location where it will not be
affected by water drips or splashing.
Ensure that ventilation to the boiler is not impeded
by towels, linen etc placed very close to the boiler.
Do not place towels or linen on top of the boiler.
The figure below shows minimum recommended
clearances.
Re ommended minimum learan es.
3.3.2. Fitting the boiler hanging bra ket
Fix the hanging bracket (see page 12 No. ) to the wall using suitable plastic plugs and M8 or M10 screws (not
supplied). Decide the position of the bottom of the boiler, giving due consideration to the recommended minimum
clearance and then drill holes to accept the boiler mounting plate.
Screw points should to be drilled the following
distances above the bottom of the boiler casing
RS – E 624mm
Plus – E 610mm
PTV – E 625mm
3.3.3. Re ommendations for handling
Clear the route before attempting the lift.
Ensure safe lifting techniques are used – keep
back straight – bend using legs. Keep load as
close to body as possible. Do not twist –
reposition feet instead. If 2 persons performing
lift, ensure coordinated movements during lift.
Avoid upper body/top heavy bending - do not
lean forward/sideways. Oso recommend
wearing suitable cut resistant gloves with good
grip to protect against sharp edges and ensure
good grip. Always use assistance if required.
Wall mounting
Important Note: If the boiler is to be fitted in a timber
framed building ensure that the bra ket is se ured to a
substantial part of the timber frame apable of taking the
weight of the boiler.
Positioning of Applian e for Final Installation (See diagram above)
Lift up boiler ( ) above hanging bracket (2), gently lean it to the wall (1) and slide it down to hanging bracket (2).
2
1

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Page 10
3.3.4. Removing/fixing the front and top ase
Grasp the front case by its sides, pull it towards the front and remove it by
lifting it off the unit, push top cover towards back and lift it off the unit.
3.4. Plumbing & Heating installation & ommissioning
3.4.1. Installation
On RS - E boilers fit the supplied safety valve to the heating return point on the installation– see point 12 page 4
diagram. Ensure that no valve is placed between the safety valve and the boiler.
To avoid draining the entire primary system during boiler maintenance it is recommended that isolation valves are
fitted to the flow and return pipes immediately below the boiler.
Connect the primary flow and return pipes for the central heating system to the labeled connections on the boiler.
Connect the mains water supply via a filling loop to the charge and discharge valve on the boiler incorporating a
stop valve and double check valve which must be left disconnected after commissioning.
Drain taps must be located in accessible positions which permit the draining of the whole system including the
primary and the secondary (dhw) system.
Any water loss from the system should be replaced from the filling loop connection.
When draining the boiler allow air in using the boiler venting valve. Do not drain the boiler by opening the
pressure relief valve.
All capillary joints in all DHW pipework must be made with lead free solder.
The Plus - E and PTV - E are self contained system boilers that manage heating flow to the radiators and or
under floor. The PTV – E also supply heat to a domestic hot water cylinder. External motorized valves are not
required (excepting when a PTV – E is connected to an Unvented Water Heater) and therefore systems such as
S & Y plan are not applicable. As motorized valves are not used a bypass is not normally required. Product
diagrams on pages 6 & 8 display the expansion vessel and pumps.
Plus - E and PTV – E can also be used on an open vented central heating system.
Wherever possible all pipe work should be insulated to help prevent heat loss and possible freezing, particularly
where pipes are run through roof spaces and ventilated under-floor spaces.
3.4.2. An illary omponents
On RS - E boilers a boiler pressure gauge, circulation pump and expansion vessel must be fitted, see diagram
page 6. The expansion vessel should be sized to the total system volume. The water capacity of the boiler itself is
6 liters.
Diagram of recommned pump on RS-E for radiator heating Diagram of recommned pump on RS-E for underfloor heating
If the capacity of the in built expansion vessel on Plus - E & PTV - E is not sufficient for the heating system
(indicated by pressure increase of 0.6bar when system is heated), an additional expansion vessel can be installed
external to the boiler. This should be fitted to the return pipe as close as possible to the boiler.
To comply with Part L of building regulations, a room thermostat must be fitted with the boiler. This will work in
conjunction with the boiler software and outside temperature sensor to finely control the temperature in the

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Page 11
dwelling and minimize energy consumption. The room thermostat should not be sited in direct sunlight or close to
any heat source such as radiators. Thermostatic radiators valves may also be used, but should not be fitted in the
same room as the room thermostat.
After the central heating circuit has been installed open all service valves, flush pipes through and check for leaks
before commissioning and introduce the correct inhibitor for a central heating circuit in accordance with BS759 .
Commission the boiler slowly to allow air to escape through the automatic air vent. Remove air from pump using
front screw on pumps.
Pressurize the system to 1.5 bar.
Where the boiler is being retro-fitted to an existing installation, it is equally important to flush the system and
commission using inhibitor to BS759 .
TERMO boilers are fitted with an automatic and manual air vent. The boilers are also equipped with an air-
indicator which detects the presence of air in the boiler. If air is detected and It exceeds the permitted level, air-
indicator switches off immersion heaters and circulation pump remains active, so that air is allowed to escape
easily. Once the air is dispelled the immersion heaters will be active.
3.5. Conne tion to the ele tri al mains supply
Before working with the appliance, turn off the power supply (MCB) and secure against restart.
This device must be earthed.
Check that the electrical supply to the building has sufficient current and voltage to supply the boiler and other
appliances to be used.
Miniture circuit breakers (MCB) must be fitted in the wiring prior to the boiler. For MCB ratings see table on page
12.
Measure exact voltage between L and N lines prior to connecting boiler, if it 10% higher than nominal voltage on
appliance, appliance itself can be damaged.
Connect the boiler to the mains using a double pole linked switch
with mm contact gap in both poles. There is an RCD switch factory
fitted inside the boiler. Supply cables must be connected to the
RCD switch inside the boiler as shown below. Stretching force of
the network connection is ,5 Nm.
In order to connect the power supply cable, the power connection
protection cover (1) must be removed by unscrewing two screws
and pulling the protection cover down. The lower protection cover
(4) should also be removed to facilitate access to the wiring points.
The Power cable must be connected directly to the RCD (2), earth
must be connected to a separate terminal ( ). After connecting the
power cable, the protective cover (1) must be replaced and securely
fastened.
Upon completion of electrical installation, carry out preliminary
safety checks according to BS7671:2001
Note: Power cables from Ø6 mm to Ø20 mm must be connected
from the left side of boiler and the protective cover (see 1 above)
must be secured, the power cables in excess of Ø20 mm
Power supply onne tion
must be connected from the bottom side of the boiler (see 4above) using the provided entry point.
Ensure that the wires are securely fixed.
The appliance must be connected to mains electricity and tested according to current IEE regulations. An NICEIC
inspection and completion certificate must be issued.
All exposed pipework must be earthed according to current IEE regulations
Boilers with power 10.8kW and 14.4 kW Boilers with power 4.8, 6, 7.2 kW
RCD onne tion lose-up

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Page 12
3.6. Room thermostat, temperature probes and pumps onne tion
Removable connectors for room thermostat, pumps and
temperature probes are located on connections plate as
shown (right). Available connectors are dependent on
boiler type and boiler options.
Power supply to control unit:-
L - Live feed to external unit
N – neutral to external unit
PE – earth to external unit
– switched live from external unit for DHW
4 – switched live from external unit for space heating
Connections plate
3.6.1. Conne t room thermostat/programmer
When connecting the room thermostat, follow thermostat manufacturer’s instructions to connect to Termo boiler.
The boiler is supplied with a fixed link between L and 4. If an external control device (room thermostat and/or
programmer)is used, remove this link. The boiler’s terminals , 4 and L N PE (power supply for control unit) are
for connection to room thermostat/programmer.
3.6.2. Fit external temperature sensor
The external temperature sensor (delivered with boiler) must be fitted in a permanently shaded area to prevent
sudden temperature changes through exposure to direct sunlight. When fitting the sensor please observe arrow
marking top position (can be seen when protective cover is removed). The sensor is an integral part of the
temperature compensation principle and must be fitted as the Plus – E & PTV – E boilers cannot operate correctly
without it.
Use twin core cable diameter 0,6mm2 to 1,5 mm2, to connect external temperature sensor,
The boiler is supplied with a factory mounted resistor connected to the outside temperature sensor port that
simulates the outside temperature at -1 ºC for testing purposes only. After installation and initial testing, the
resistor must be removed and wires from the external temperature sensor must be connected to the sensor port.
(Circled port on diagram below right).
protective cover
base
External temperature sensor
External temperature sensor connection point
on boiler's connection plate

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Page 1
3.6.3. Fitting hot water ylinder temperature sensor (PTV-E only)
The PTV – E has a temperature sensor supplied with the boiler which must be fitted to the domestic hot water
cylinder as this ensures a correct reading of the secondary (DHW) temperature.
Use twin core cable of diameter 0.6mm2 to 0.75
mm2. The cable runs from the boiler to the hot
water cylinder and the probe should be inserted
approximately 0% of the way up the cylinder and at
least in the top half of the area covered by a heating
coil. The probe must be touching the cylinder wall
and held in place using the cylinder insulation.
Alternatively a thermostat pocket can be used if
available and in the correct position.
Water Cylinder temperature sensor
Water cylinder temperature sensor connection point
on boiler's connection plate
3.6.4. Fitting pump onne tions and expansion vessel (RS – E only)
Termo RS – E requires expansion vessel and pump(s) to be connected to the heating circuit according to diagram
on page 6. Circulation pumps for central heating and hot water should be connected to connections plate
according to diagrams in Appendix 1.
Termo Plus and PTV boilers are supplied with pumps and expansion vessel factory fitted and pumps wired to the
connections plate.

The company reserve the right to alter size, shape and specification without prior notice
Page 14
4. Setting up Boilers
RS - E & Plus - E – Space heating with outdoor temperature compensation
PTV - E – Space heating with Outdoor temperature compensation and domestic hot water
4.1. Control Panel (in luding fault finding indi ators)
1. Display
Default display is of current primary temperature inside the boiler. Temperature range is -19
o
C (below -19
o
C the
display shows - -) up to + 99
o
C (above +99
o
C display blinks).
Following warning signals can be displayed:
 P1 – anti freeze protection for secondary (DHW) is active
 P2 – anti freeze protection for central heating is active
 o1 or c1 – thermal sensor for primary temperature isn't connected or is short-circuited
 o2 or c2 – thermal sensor for external temperature isn't connected or is short-circuited
 o3 or c3 – thermal sensor for secondary (dhw) temperature isn't connected or is short-circuited
2. Led diodes of heater stages in use
LED diodes light to show how many heating elements are active.
3. Led diode OK/air in boiler
If there is no air in the boiler, the diode lights green. If air appears in the boiler, the diode lights red and the
boiler shuts down. Upon de-aeration, the diode automatically changes the color to green and operation of the
boiler continues.
4. Led diode insufficient supply voltage
Lights red if the net voltage is below 170 V and the boiler shuts down.
5. Led diode for central heating
Indicates the operation of heating circulation pump, provided that the room thermostat is on.
6. Push button to adjust central heating programming.
7. entral heating switch (0 – standby, 1 – on)