REMEHA Avanta 18v Manual

1
• Wall hung high-efficiency
condensing boiler
for open vented systems
• Output 19 kW
Remeha Avanta 18v
Installation and service manual
Remeha Avanta 18v

2
Remeha Avanta 18v
TABLE OF CONTENTS
INTRODUCTION 4
1 SAFETY 5
1.1 General safety 5
1.2 Safety during assembly and installation 5
1.3 Safety during installation, inspection and maintenance 5
2 INSTALLATION 7
2.1 Scope of delivery 7
2.2 Mounting the boiler 7
2.2.1 Clearance requirements 7
2.2.2 Dimensions and connection points. 8
2.2.3 Mounting the Remeha Avanta 18v 9
2.3 Water-side connections 9
2.3.1 Water flow 9
2.3.2 System Pump 9
2.3.3 Pressure loss of the boiler 10
2.3.4 Open-Vented System 10
2.3.5 Sealed systems 10
2.3.6 Additional guidelines for the domestic and CH water 10
2.3.7 Water treatment 11
2.3.8 Safety valve discharge 12
2.3.9 Draining Provision 12
2.3.10 Connecting the ‘CH return’ 12
2.3.11 Connecting ‘CH flow’ 12
2.3.12 Connecting condensate drain 13
2.4 Gas-side connections 13
2.4.1 Additional guidelines for gas connections 13
2.4.2 Adjusting boiler to other gas-type 13
2.4.3 Connecting the gas supply 14
2.5 Flue terminal and air supply connections 14
2.5.1 Flue terminal positions 14
2.5.2 Room sealed flue 16
2.5.3 Connecting the flue terminal and air supply 16
2.6 Electrical connection 17
2.6.1 The control unit 17
2.7 Connecting external controls 18
2.7.1 Connecting an on/off control – room temperature (volt free switching) 19
2.7.2 Connecting a time control using an external 230 V clock 20
2.7.3 Connecting a 230 V time clock in combination with a modulating room control 20
2.7.4 Connecting a modulating control – room or outside compensation 21
2.7.5 Connecting an outside temperature sensor 21
2.7.6 Connecting the DHW sensor/thermostat 22
2.7.7 Connecting a three-way valve 22
2.7.8 Connecting a frost thermostat 22
2.7.9 Connecting an external interlock 23
2.7.10 Connecting remote alarm and boiler run indication 23
2.7.11 Connecting a PC/PDA 24
2.8 Connecting an external pump 24
2.9 Wiring diagram 25

3
2.10 Commissioning 26
2.10.1 Control Panel 26
2.10.2 Additional guidelines for commissioning 26
2.10.3 Putting the boiler into operation 26
2.10.4 Normal start-up procedure 32
2.10.5 Error during the start-up procedure 32
2.10.6 Read out settings 33
2.10.7 Adjust the boiler according to the system 34
2.10.8 Changing the parameters at service level (with access code) 34
2.10.9 Changing the maximum output (Hi) for CH operation 37
2.10.10 Restore factory settings 38
2.11 Putting the boiler out of operation 38
2.11.1 Boiler with frost protection, during longer periods of non-use 38
2.11.2 Boiler without frost protection, during longer periods of non-use 38
3 INSPECTION AND MAINTENANCE 39
3.1 Inspection 39
3.1.1 Checking the flue pipes and air supply pipes for leaks 39
3.1.2 Checking the condensate siphon 40
3.1.3 Checking the ignition electrode 40
3.1.4 Checking the combustion 41
3.2 Maintenance 42
4 ERRORS 46
4.1 General 46
4.2 Error codes 46
4.3 Control stop or lock-out 49
4.4 Error memory 49
4.4.1 Error read outs 50
4.4.2 Deleting errors 50
5 SERVICE PARTS 51
5.1 General 51
6 EC DECLARATION 54
7 REGULATIONS 55
7.1 EC regulations 55
7.2 Remeha factory test 55
7.3 Additional guidelines 55
8 TECHNICAL SPECIFICATIONS AND WORKING PRINCIPLE 56
8.1 Technical data 56
8.2 The boiler components 57
8.3 Working principle 57
8.3.1 Regulating 57
8.3.2 Advanced boiler control (‘abc®’-control) 58
8.3.3 Regulating the water temperature 58
8.3.4 Low flow / water protection 58
8.3.5 High Limit temperature protection 58
9 EFFICIENCY DATA AND GAS EFFICIENCY LABELS 59
9.1 Annual efficiency 59
9.2 Water-side efficiency 59

4
Remeha Avanta 18v
INTRODUCTION
The Remeha Avanta 18v is a wall mounted high-efficiency fully
condensing central heating boiler, for open vented systems
These technical instructions contain useful and important infor-
mation for the correct installation, operation and maintenance
of the Remeha Avanta 18v boiler.

Read these instructions carefully before putting the boiler into
operation, familiarise yourself with their control functions and
operation, strictly observing the instructions given. Failure to
do so may invalidate warranty or prevent the boiler from
operating correctly.
The installation, commissioning, Inspection and servicing of
the boiler must be carried out by a competent Corgi registered
Engineer who holds valid ACOPS certification and in accord-
ance with current gas safety (installation and use) regulations,
the building regulations and all other relevant codes of prac-
tice.
All electrical work must be carried out by a competent Engi-
neer and to be installed in accordance with the current IEE
regulations.

On commissioning the certificate in the Boiler Service Log
book (supplied with the boiler) must be completed and left on
site with a copy send on to Broag Ltd for registration purposes.
If you have any questions, require an engineer to call on site,
or if you need more information about specific subjects relating
to this boiler, or it's installation please do not hesitate to con-
tact our technical help line 0118 978 3434.

When contacting Broag with a problem on the boiler please
have available the boiler type, Serial No (located on the
bottom of the casing), and the symptoms or fault code (the
fault code is a series of flashing red digits in the display panel).
The data published in these technical instructions is based on
the latest information (at date of publication) and may be sub-
ject to revisions.
We reserve the right to continuous development in both design
and manufacture, therefore any changes to the materials or
technology employed may not be retrospective nor may we be
obliged to adjust earlier supplies accordingly.
59970LTGBW7H046a
59970LTGBW7H046

5
1 SAFETY
1.1 General safety
The following pictograms are used in this Installation and Serv-
ice manual to specifically draw certain points to your attention:
Tip  Useful tip or practical advice.
Indication  Important instruction in carrying out
a particular operation.
Warning  Possible danger of personal injury or
material damage to the regulator, building
or environment.
Danger  Serious personal injury can occur
because of risk of electric shocks.
1.2 Safety during assembly and installation
Observe the appropriate safety measures, as given in these
instructions.

Can you smell gas? What to do:
• do not smoke and do not create any flame or sparks;
• do not use any electric switches;
• turn off the gas tap;
• open windows and doors;
• trace possible leaks and seal them.
Warning! If the leak is before the gas meter, alert your gas
supplier, TRANSCO, tel. [phone].

Can you smell smoke or flue gasses? What to do:
• isolate power supply
• open windows and doors
• trace possible leaks and seal them.
1.3 Safety during installation, inspection and
maintenance
Under the Gas Safety (Installation & Use) Regulations 1998,
the Remeha Avanta 18v, in common with all gas appliances,
must be installed by a competent person in accordance with
that regulation.
Statutory regulations, in any country, cannot be overridden by
any of the notes or instructions from the manufacturer.
Compliance with National Standards does not provide any
degree of immunity from legal obligations. In the UK, the
installation must be in accordance with the national and local
norms and requirements.

6
Remeha Avanta 18v
For any issues or circumstances not addressed within these
instructions, please call our Customer Care Department.
Remeha Avanta 18v - PIN: 0063BQ3009
Gas Council numbers: Remeha Avanta 18v: 41-288-06
Classification type for evacuation of the combustion products;
according EN 483: see par. 8.1.
Health and safety information
• All sealants and gaskets are free from harmful products.
On first firing the boiler, a smell of these products may be
present and should cease after a short period.

7
2 INSTALLATION
2.1 Scope of delivery
The standard delivery of the Remeha Avanta 18v boiler
includes:
- Boiler + mounting bracket
- Installation and Service manual, Quick reference card and
Mounting Template
- Boiler Service Log Book
- Wiring diagrams
- Gas cock with gasket + 90° gas pipe ( 22 mm)
- nylon plugs and screws for fixing mounting plate
- olives and nuts
- spacers
- cable glands;
This Installation and Service manual deals with the standard
supplied boiler only. For the installation or assembly of any
optional accessories supplied with the boiler, such as stand off
frame, pipe work kits, cover plate, control kits, etc, please refer
to the Assembly Instructions supplied with these accessories.
2.2 Mounting the boiler
Packed in the box with the Remeha Avanta 18v box is this
Installation and Service manual. Read instructions and
remarks carefully. This section includes the guidelines and
instructions for the connection of gas, water, electricity, safety
devices, the regulator, control unit, flue discharge and air sup-
ply.
2.2.1 Installation / maintenance clearance requirements
The gas connection is located on the bottom of the boiler
whilst the water connections, air inlet and flue gas outlet are
located on the top of the boiler. The boiler is supplied as
standard with gas pipe work tails.
For installation, servicing and inspection min. 600 mm in front
of the boiler is required. If this free space is obtained by open-
ing a door or removing a panel, the boiler may be installed
for instance in a closed cupboard. All servicing / inspection /
repairs are made from the front of the boiler.
For ease of installation we recommend clearances of 0.5 cm
at the side so that the unit is easy to open, with a free space
of 25 cm under the appliance and 25 cm above the appliance,
as the minimum requirement.
However once installed, it is possible to reduce these clear-
ances to 22 cm at the top, and 25 cm at the bottom provided
the boiler front panel can be removed and the isolating valves
are easily accessible without the use of tools”
59970.LT.GB.W7H.006

8
Remeha Avanta 18v
400
min.1000290
min.
250
min.
250
600
59970LTGBW7H047a
600
22
679
400
85
206
50
317
160
290
132,5
40
40
88
94
59970LTGBW7H001d
147
49
59970LTGBW7H047

Clearances shown are for ease of installation – once fitted it is
possible to enclose the boiler in a cupboard with 25mm
clearances around the casing provided a door is included to
allow the front cover to be removed completely for maintenance
and allowance is made to access the gas valve and flow /
return connections.
59970.LT.GB.W7H.001
2.2.2 Dimensions and connection points.
 Return connection Ø 22 mm
 Flow connection Ø 22 mm
 Gas connection Ø 22 mm
 Combustion air inlet Ø 100 mm (concentric)
 Flue duct Ø 60 mm (concentric)
 Condensate drain connection ¾” (standard overflow pipe
size)

• Based on the guidelines and the required installation
space, determine where to mount the Remeha Avanta
18v.
• In determining the boiler position, consider carefully the
flue outlet position and any pluming consequences.

9
59970LTGBW7H002c
2x
ø8 mm
2.2.3 Mounting the Remeha Avanta 18v
• Remove template from the box.
•
Using the template determine and mark the position of the
mounting bracket and flue outlet.
• Drill the (Ø 8 mm) holes.
• Fit the (Ø 8 mm) plugs.
• Core drill the (Ø 125 mm) hole for the flue outlet
• Fit (Ø 6 mm) screws into the plugs.
• Remove boiler from the box and mount on bracket.

• The boiler should be mounted on a suitable vertical wall
which is able to support the weight of the boiler.
• The boiler should be mounted in a room which, even
during severe cold weather, remains frost-free, or frost
protection controls MUST be fitted.
• If the boiler is to be installed in a timber framed building,
please refer to British Gas publication: ‘Guide for Gas
Installations in Timber frame Housing’, reference DM2.

• Make sure the boiler and any open connections are
protected from building etc. dust during the installation.
• There must be a 3 amp fused switched spur within 1 m of
the boiler.
• Provision must be made for the condensate discharge.
2.3 Water-side connections
2.3.1 Water flow
The central heating system should not require a bypass,
unless all radiators are fitted with TRV’s or when the system
controls could allow the boiler and pump to operate when
there is no flow. Where a bypass has to be fitted, the bypass
must be placed at least 1.5 metres away from the boiler.
The ‘abc®’ control also monitors the temperature difference
across the flow and return connections and the rate of tem-
perature rise and will automatically regulate the boiler output
to ensure that it remains operational for as long as possible
without the need to ‘lock out’ requiring a manual reset.
2.3.2 System Pump
The system pump must be wired directly to the boiler terminal
strip and be capable of providing the nominal flow at design
conditions against the combined resistance of the boiler and
system.
The minimum flow rate is 1.05 m3/h (0.29 l/s) at maximum heat
input and 15°C differential across flow and return. To operate
at 81°/70°/C the flow rate must be 1.37 m3/h (0.38 l/s)
Higher resistance systems may require a higher duty pump.
The maximum power consumption of the pump may not
exceed 150 W /1.5 amps.
The connection of the pump is described in par. 2.8
59970.LT.GB.W7H.002

10
Remeha Avanta 18v
Pressure Loss Graph
Pressure Loss [mbar]
Waterflow [m3/h]
100
200
300
400
500
600
700
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2
59970LTGBW7H003a
Recommended T 11oC
T max. 20oC
Feed and
exansion
cistern
Flow
Return
Max. 150 mm
Cold feed
Min. 15 mm
Heating vent
Min. 22 mm
Min. 450 mm
Static head
Min. 1 m
59970LTGBW7H004b
2.3.3 Pressure loss of the boiler
2.3.4 Open-Vented System
The feed and expansion tank must be situated at a minimum
height of 1 metre and a maximum height of 30 metres above
the boiler to provide the correct operating head pressure.
The cold feed must be at least 15 mm and the open vent must
be at least 22 mm. The pipes must rise continuously from the
system. The heating vent must be at least 450 mm above the
water level in the feed and expansion cistern.
The pump should be fitted on the flow pipe from the boiler and
have isolating valves each side.
2.3.5 Sealed systems
If the Avanta 18v is installed on a sealed system, an appro-
priately sized expansion vessel and a safety valve MUST be
installed close to the inlet side of the pump. A mains filling
loop MUST be installed close to the outlet side of the system
pump, along with automatic air vents positioned in the system
pipe work to ensure adequate system venting during filling and
operation. An adequate pressure gauge should be fitted in a
position where it can be seen during filling of the system.
All in accordance with the current issue of the relevant British
Standards.
2.3.6 Additional guidelines for the domestic and CH
water
•
Power flush the pipes and radiators thoroughly before con-
necting the boiler to the central heating system in accord-
ance with BS 7593 (1992).
•
Following power flush, re-fill the system with clean tap water
and run the system up to 60°C – turn boiler off and allow
to cool slightly, then completely drain system from all low
points. Re-fill system.

• The temperature of the central heating pipes and the
radiators can rise to 95°C.
• Use untreated tap water only to fill the CH system.
•
The pH value of the system water must be between 6 and 9.
• In case inhibitors are being used, please follow the
instructions given in, see par. 2.3.7.
59970.LT.GB.W7H.003
59970.LT.GB.W7H.004

11
2.3.7 Water treatment
If used correctly water treatment can improve the boilers
efficiency and increase the anticipated life expectancy of the
boiler. For further information a special document “Quality
requirements CH water” is available from Broag.
As most systems contain a variety of metals, it is considered
good practice to provide some form of water treatment in order
to prevent or reduce the following:
• Metallic corrosion
• Formation of scale and sludge
• Microbiological contamination
• Chemical changes in the untreated system water

All scale deposits however small will reduce the efficiency of
the boiler and should be prevented.
Suitable chemicals and their use should be discussed with a
specialist water treatment company prior to carrying out any
work (environmental aspects, health aspects). The specifica-
tion of the system and manufacturers recommendations must
be taken into account, along with the age and condition of
the system. New systems should be flushed thoroughly to
BS 7593(1992) to remove all traces of flux, debris, grease
and metal swarf generated during installation. Care to be
taken with old systems to ensure any black metallic iron oxide
sludge and other corrosive residues are removed, again by
power flushing, ensuring that the system is drained completely
from all low points.

Please ensure that the new boiler plant is not in circuit when
the flushing takes place, especially if cleansing chemicals are
used to assist the process.
It is important to check the inhibitor concentration after installa-
tion, system modifications, filling the system and every service
in accordance with these instructions.
For the correct dosage and the suitability of inhibitors for use
with our boilers and for further information on water treatment
or system cleaning we advise direct contact with either of the
following companies:
‘Copal®’ or: Sentinal ‘X100®’
manufactured by: manufactured by:
Fernox, Cookson Electronics BetzDearborn Ltd
Forsyth Road Sentinal
Sheerwater Foundry Lane
Woking Widnes
Surrey GU21 5RZ Cheshire WA8 8UD
Tel No: 01483 793200 Tel No: 0151 424 5351
Fax No: 01483 793201 Fax No: 0151 420 5447
Email: [email protected]
Web site: www.fernox.com

12
Remeha Avanta 18v
59970LTGBW7H005a
59970LTGBW7H007a
2.3.8 Safety valve discharge
A pressure relief safety valve is not needed for Open-Vented
systems.
2.3.9 Draining Provision
Drain points must be provided at all the low points of the
system to ensure that the entire system can be completely
drained. The boiler is provided with a drain in the return pipe.
2.3.10 Connecting the ‘CH return’
•
Remove the dust cap from the ‘CH return’ connection 
at the top of the boiler.
• Fit the return pipe to 22 mm Ø compression fitting.
59970.LT.GB.W7H.005
59970.LT.GB.W7H.007
2.3.11 Connecting ‘CH flow’
•
Remove the dust cap from the ‘CH flow’ connection 
at the top of the boiler.
• Fit the flow pipe to the 22 mm Ø compression fitting.

13
59970LTGBW7H034a
2.3.12 Connecting condensate drain
•
Connect the condensate drain outlet  to a suitable waste
water drain point using acid resisting pipe work (i.e. - ¾”
overflow). To enable the siphon in the boiler to be removed
/ serviced, the connection should not be a permanent one
(i.e. “push fit” system or a “tundish” immediately below the
boiler).
•
To prevent the risk of freezing connect the condensate into
an internal vertical soil pipe using a tundish (air break) c/w a
min 75 mm water seal trap.
•
If the condensate pipe has to run externally make sure
this is done by realizing the shortest possible route, and
increase the diameter to at least 1¼” or insulate it with
weather resistant insulation.
•
The drain should slope at least 3 cm per meter, with a maxi-
mum horizontal length of 5 m.

• If connecting into an internal discharge branch (i.e. sink
waste etc) the connection must be down stream of the
existing waste trap.
• Fill the boiler siphon with water before operation, to
prevent flue gasses discharging into the room.
• The condensate drain must be connected in accordance
with current regulations.
2.4 Gas-side connections
2.4.1 Additional guidelines for gas connections

Before installation, check that the gas meter has sufficient
capacity for the demand. Remember to consider the
consumption of all household appliances.
2.4.2 Adjusting boiler to other gas-type
The Avanta 18v boiler is suitable for both natural gas and pro-
pane firing.
The boiler is supplied as standard set for natural gas (H),
therefore the following procedure must be carried out
BEFORE the boilers are fired and commissioned for the first
time on propane:
Adjust the fan speed (see par. 2.10.8) and adjust the gas/air
ratio (see par. 2.10.3).
59970.LT.GB.W7H.034

14
Remeha Avanta 18v
59970LTGBW7H035b
2.4.3 Connecting the gas supply
•
Before starting any work on the gas supply, turn off the main
isolation valve.
•
Remove the dust cap from the gas connection  at the
bottom of the boiler.
•
Connect the gas supply to the 22 mm Ø connection (copper
tail supplied).

• Make sure there is no dirt in the gas pipe. Blow through
the pipe before installation or tap well to clear.
• Make sure that there is sufficient gas pressure available
(at full load > 17 mbar).
• Preferably install a gas filter in the gas pipe to protect the
boiler.
• The gas supply must be connected, tested for soundness
and purged by a qualified Engineer and in accordance
with BS6891.
2.5 Flue terminal and air supply connections
The Remeha Avanta 18v is only suitable for room sealed
operation with a standard concentric connection 60/100 mm Ø
or the optional 80/125 mm Ø connection.
Detailed recommendations for air supply and flue terminals are
given in BS 5440.
2.5.1 Flue terminal positions
The flue terminal must be located with care to ensure that the
products of combustion are dispersed properly in all weather
conditions and cause minimum nuisance to the building user
or any adjacent buildings. If the terminal is positioned less
than 2 m above the ground, balcony, or flat roof where access
by persons is possible a suitable guard must be employed.

The boiler will produce a water vapour plume during normal
operation.
Positions for the Remeha Avanta 18v are shown in the figure
and table 01.
59970.LT.GB.W7H.035

15
G
G
A
A
B
600 mm
600 mm
2000 mm
D,E
S
S
F
P
H
C
J
J
L
M
K,N
No flue must penetrate
area within dotted lines
round roof light
LTALW7H000020a
Dimensions Terminal location Minimum distance
(in mm) to terminal
(room sealed)
A Directly below an opening, air brick,
opening window, etc. 300
B Above an opening, air brick, opening window, etc. 300
C Horizontally to an opening, air brick,
opening window, etc. 300
D Below a gutter or sanitary pipe work 40 1)
E Below the eaves 40
F Below a balcony or carport roof 40
G Above ground, roof or balcony level 300
H From vertical drain/soil pipe work 40 1)
J From an internal or external corner 40
K From a surface or boundary facing the terminal 600 2)
L Vertically from a terminal on same wall 1500
M Horizontally from a terminal on same wall 300
N From a terminal facing the terminal 1200
P From an opening in a carport (e.g. door, window) into the building 1200
R From a vertical structure on the roof n/a
S Above an intersection with the roof n/a
LT.AL.W7H.000.020
table 01 Minimum distances to terminal
1) = For combustible materials the min should be 150 mm
2) = Where the terminal is positioned directly opposite an open-
ing in the facing wall the min will be 2 m.
n/a = not applicable.

16
Remeha Avanta 18v
2
1
59970LGBW7H010a
min. 275 mm
ø 125 mm
2
1
59970LTGBW7H008a
L
VRS roof
mounted
room sealed
terminal
59970LTGBW7H009a
L
80/125 or 60/100
LTNLW6H000031A
LTNLW6H000032A
2.5.2 Room sealed flue
See table 02 for the maximum pipe length of flue ducts and air
supply pipes for this ‘room sealed’ application.
It is not necessary to provide combustion air to the room or
internal space in which the boiler is installed.
Standard M&G material
Diameter in mm Ø 60/100 80/125 60/100 80/125
Maximum length ‘L’ allowed [m] 2 20 8 34
Eq. Length of 90° elbow
2 1.4
Eq. Length of 45° elbow
1 0.65
table 02 Maximum pipe lengths for flue duct and air supply
in room sealed application

For flue installations not covered by this booklet, please
contact our technical help line 0118 978 3434.
2.5.3 Connecting the flue terminal and air supply
•
Check the depth of the wall and cut the terminal to suit
– taking note of the cutting instructions supplied with it
•
Core drill a 125mm Ø hole in the wall, fit the rubber closure
plate at the exit end and slide the terminal through the wall
until the closure plate is clear of the outer edge of the wall
– pull back the terminal till the closure plate is flush then fit
inner wall closure to secure.

• All connections must be airtight and waterproof.
• Horizontal extension sections should slope towards the
boiler (at least 3 cm per metre).
59970LTGBW7H010

17
230 V
59970LGBW7H011a
LTALW7H000023a
2.6 Electrical connection
•
Connect the boiler to the fused (3 amp) switch spur unit
adjacent to the boiler.
• The switch unit must always be accessible.

When the switch spur is on the following components of this
appliance can be live (230 V):
• electrical connection gas combination block;
• most parts of the control unit;
• ignition transformer;
• X1, X2, X4, X5, X6 and X7 terminal strip;
• 230 V supply cable connection.
59970LTGBW7H011
LTALW7H000023
2.6.1 The control unit
The Remeha Avanta 18v has an electronic regulation and con-
trol unit with an integrated ionisation flame detector. The heart
of the boiler control unit is a microprocessor, the ‘abc®’, which
controls and protects the boiler.
The maximum rated input of the boiler is 130 W. The boiler is
fully pre-wired internally, all external connections can be made
using the terminal strips X5 - X7 - X9 and 230 V input (X2 ter-
minal). See the diagram for the position of the connectors and
fuse (F2) on the control unit.
The most important properties of the control unit are summa-
rized in table 03.
Manufacturer Sit Controls
Supply voltage 230 V – 1ph – 50 Hz
Pre-purge time 3 s
Post-purge time 5 s
Ignition time 2.5 s
Safety time 5 s
Anti-cycling time 3 till 10 min.
Fuse value F1 (230 V) 2 AT
DC fan 24 VDC
table 03 Control unit characteristics

Any loads other than those specified above are only allowed if
an isolating transformer is used.

18
Remeha Avanta 18v
59970LTGBW7H012b
The output of the Remeha Avanta 18v can be controlled in the
following ways:
On/off control – volt free switching - The boilers internal
control will modulate the output to achieve the flow tempera-
ture set point of the boiler. This contact is on the X9 terminal
strip (low voltage only).
On/off control – 230 V switching - The boilers internal con-
trol will modulate the output to achieve the flow temperature
set point of the boiler. This contact is on the X2 terminal strip
(230 VAC only).
Modulated control – Open Therm - The external controls will
modulate the boiler’s output to achieve the flow temperature
determined by the modulating regulator. This contact is on the
X9 terminal strip (low voltage only).
Modulated control – Open Therm in combination with an
externally mounted simple 230 V switching time clock -
The boiler will provide room compensated heating and time
control over CH and DHW (System boiler).

• All connections on terminal X1, X2, X4, X5, X6 and X7
are 230 VAC.
• All connections on terminal X9 are low voltage only.
2.7 Connecting external controls
•
Release the two screws at the bottom of the front casing,
release plastic clip below display and remove the front cas-
ing.
•
Remove one of the supplied grommets in the base of the
boiler, fit a cable gland and feed the cables through.
•
Connect the cables to the relevant connectors, as shown in
the diagrams.

• Isolate power supply at the fused spur before carrying out
any work on the boiler controls.
59970LTGBW7H012

19
LTALW7H000025g
230v - 3 Amp
Power Supply
Terminal
Block X5
X2
X5
X4
X6
X7
X9
Terminal
Block X9
Exist
links
Exist
links
Terminal
Block X2
1Neutral
2Open valve to DHW (230v)
3Open valve to HTG (230v)
Outside sensor (red band) for direct boiler weather compensation
or when used in conjuction with a compatable Open Therm
control eg: Chronotherm or Celcia 20
DHW sensor (red band) or volt free thermostat (make on temp fall)
Remove existing link to use this function
External interlock (volt free)
Remove existing link to use function
Modulating - using Open Therm control
eg: Honeywell Chronotherm or Celcia 20
On / Off - using volt free switching control
eg: Celcia 10 or low volt room thermostat
NOTE: Terminal blocks are not in line as shown - diagramatic only
For external DHW priority
diverting valve on System boiler
when used in conjunction with
"Open Therm" compensation
Terminal
Block X7
Terminal
Block X6
1
2
Common Alarm
(Closes on alarm) Boiler Run
(Closes on run)
3
1
2
3
4
5
6
7
8
1
2
L
N
3
4
5
E
E
Power supply to internal or external time clock -230v
Switch live (230v) from external time clock DHW demand
Remove existing link 4-3 to use this function
Switch live (230v) from external time clock HTG demand
Remove existing link 4-1 to use this function
- Neutral
- Live
2
1
Terminal
Block X4
- Live
- Neutral
System pump
2
1
4
3
LTALW7H000026b
X9
Terminal
Block X9
Modulating - using Open Therm control
eg: Honeywell Chronotherm or Celcia 20
On / Off - using simple volt free switching control
1
2
3
4
5
6
7
8
Exist
links
2.7.1 Connecting an on/off control – room temperature
(volt free switching)
The Remeha Avanta 18v can be connected to a 2-wire on/off
thermostat, such as the Remeha Celcia 10.
Mount the thermostat in a reference room (usually the living
room).
•
Remove existing link and connect the 2-wire 24 V room
thermostat to connectors 7 and 8 of the X9 terminal strip.

If a room thermostat with an anticipation resistor is being
used, parameter p5 should be changed from 0 to 1, see
par. 2.10.8.
LT.AL.W7H.000.025
LT.AL.W7H.000.026

20
Remeha Avanta 18v
LTALW7H000027e
X2
Exist
links
Terminal
Block X2
Power supply to external time clock -230v
Switch live (230v) from external time clock DHW demand
Remove existing link 4-3 to use this function
Switch live (230v) from external time clock HTG demand
Remove existing link 4-1 to use this function
5
4
N
L
3
2
1
2.7.2 Connecting a time control using an external 230 V
clock

When the switch spur is on, the terminal strip X2 will be live
(230 V).
•
A 230 V two channel time clock for CH and DHW control
can be connected to the Remeha Avanta 18v.
Live 230 V supply for the time clock - connect to connectors
4 (L) and 5 (N) on X2 terminal strip.
•
For CH - remove exist link between connectors 4 and 1 of
the X2 terminal strip and connect the 230 V output from the
time clock to terminal 1 on the terminal strip X2.
•
For DHW - remove exist link between connectors 4 and 3 of
the X2 terminal strip and connect the 230 V output from the
time clock to terminal 3 on the terminal strip X2.

For this option to function correctly, a link or room control
must be fitted between connectors 7 and 8 of X9 terminal strip
(remove existing link before use).
If the 230 V supply for the external time clock is not taken from
the boiler – terminal block X2 connections 4 & 5, it must be
taken from the same phase as the boiler 230 V supply and
correct polarities observed.
2.7.3 Connecting a 230 V time clock in combination with
a modulating room control
With an externally mounted simple 230 V switching time clock
connected to connectors on X2 terminal strip and a Celcia 15
connected to connectors 7 and 8 of X9 terminal strip (remove
existing link), the Remeha Avanta 18v will provide room com-
pensated heating and time control over CH and DHW.

An OpenTherm® room modulating control (Celcia 15) used in
conjunction with a simple external 230 V time clock will
provide easy to set up and operate - timed room compensa-
tion heating
LTALW7H000027