Sime MURELLE.HT 25 T Manual

Fonderie SIME S.p.A. 6330338B - 11/2022 - R9
Cod.
USER, INSTALLATION AND SERVICING INSTRUCTIONS
MURELLE.HT T
Condensing wall mounted boiler
EN
TRANSLATION OF THE ORIGINAL INSTRUCTIONS
To consult the documentation,
visit our website www.sime.it

2
RANGE RATED CERTIFICATION
The maximum power, in heating mode, of MURELLE.HT T boilers
can be adapted, during the installation, to the thermal needs of
the system by modifying the setting of PAR 19 in the 0 .. 100 range.
The setting of PAR 19 = 100 is the factory setting that allows the
boiler to deliver its maximum power in heating mode. It can be
reduced by modifying the setting of PAR 19 as shown in the table
appearing below.
Once the new setting of PAR 19 has been made, the reduced max-
imum power value (kW) MUST MANDATORILY be applied beside
the boiler’s data plate. For checks and adjustments after the mod-
ification, refer to the new value for the maximum power.
The useful nominal power levels used are those relative to the
operating conditions (80-60°C) (Pn min - Pn max).
Example for MURELLE.HT 25 T boiler:
–default heating power range: 1,65 - 24,2 setting of PAR 19 = 100
–“reduced” heating power range: 1,65 - 19,7 setting PAR 19 = 80
DESCRIPTION
MURELLE.HT T
25 35 Setting of PAR 19
Min Max Min Max
A - Factory power range (heating) kW 1,65 24,2 2,33 33,9
100
B - Reduced power ranges for maximum power
reduction (heating)
kW 1,65 21,9 2,33 30,7
90
kW 1,65 19,7 2,33 27,6 80
kW 1,65 17,4 2,33 24,4 70
kW 1,65 15,2 2,33 21,3 60
kW 1,65 12,9 2,33 18,1 50
kW 1,65 10,7 2,33 15,0 40
Boiler technical data plate
m
CAUTION
The grey fields must be filled in by the installer.
Range Rated label
A
B
A Factory power range
B Reduced power range for maximum power reduction

3
SAFETY WARNINGS AND REGULATIONS
m
WARNINGS
–After having removed the packaging
make sure that the product supplied is in-
tegral and complete in all its parts. If this
is not the case, please contact the Dealer
who sold the appliance.
–The appliance must be used as intend-
ed by
Sime who is not responsible for
any damage caused to persons, animals
or things, improper installation, adjust-
ment, maintenance and improper use of
the appliance.
–In the event of water leaks, disconnect the
appliance from the mains power supply,
close the water mains and promptly in-
form professionally qualified personnel.
–Periodically check that the operating
pressure of the water heating system
when cold is
1-1.2 bar . If this is not the
case, increase the pressure or contact
professionally qualified personnel.
–If the appliance is not used for a long pe-
riod of time, at least one of the following
operations must be carried out:
-
set the main system switch to "OFF";
- close the gas and water valves for the
water heating system.
–In order to ensure optimal appliance op-
erations Sime recommends that mainte-
nance and checks are carried out ONCE
A YEAR
.
–If the power cable is damaged, replace it
with a cable ordered as a spare part with
the same characteristics (type X). Assem-
bly must be by carried out by a qualified
professional.
m
WARNINGS
– It is recommended that all operators read
this manual carefully in order to use the
appliance in a safe and rational manner.
–
This manual is an integral part of the
appliance. It must therefore be kept for
future reference and must always ac-
company the appliance in the event the
appliance is transferred or sold to anoth-
er Owner or User or is installed on anoth-
er system.
–
Installation and maintenance of this ap-
pliance must be carried out by a qualified
company or by a professionally qualified
technician in accordance with the in-
structions contained in the manual. Once
the work is complete, the company or
technician will issue a declaration of con-
formity with national and local technical
standards and legislation in force in the
country where the appliance will be used.
–
Any repairs on the appliance must be
carried out solely by professionally quali-
fied personnel, using original spare parts
only. Failure to comply with these instruc-
tions can jeopardise the appliance’s safe-
ty and void the warranty with immediate
effect.
–
Fonderie SIME S.p.A. reserves the right
to make improvements to its products
at any time without prior notice, without
compromising their essential charac-
teristics. The graphic illustrations and/
or images in this document may show
optional accessories that vary according
to the country in which the appliance is
used.

4
RESTRICTIONS
d
IT IS FORBIDDEN
–To allow children under the age of 8 to
use the appliance. The appliance can be
used by children no younger than 8 years
old, by people with physical or cognitive
disabilities, and by people lacking experi-
ence or the necessary knowledge, provid-
ed that they are supervised or have been
instructed on how to use the appliance
safely and that they understand the risks
associated with it.
–To allow children to play with the appli-
ance.
–To allow unsupervised children to per-
form user maintenance and cleaning.
–To use electrical devices or appliances
such as switches, electrical appliances
etc if you can smell fuel. If this should
happen:
-
open the doors and windows to air the
room;
- close the gas isolation device;
- promptly call for professional assis-
tance.
–To touch the appliance with bare feet or
with any wet part of the body.
–To carry out any technical intervention
or cleaning operation before having dis-
connected the appliance from the mains
power by setting the main switch to
"OFF", and closing the gas supply.
–To modify the safety or adjustment devic-
es without authorization and instructions
from the manufacturer.
d
IT IS FORBIDDEN
–To block the condensate drain (if present).
–To pull, detach or twist the electrical ca-
bles coming out of the appliance even if
the appliance is disconnected from the
mains power supply.
–To expose the boiler to atmospher-
ic agents. These boilers can also be in-
stalled in partially covered areas, as per
EN 15502, with a maximum ambient tem-
perature of 60 °C and a minimum am-
bient temperature of - 5 °C. It is recom-
mended that the boiler is installed below
weathered roofs, on the balcony or in a
protected niche, to protect it from expo-
sure to weathering agents (rain, hail and
snow). The boiler is equipped as standard
with an antifreeze function.
–To block or reduce the size of the ventila-
tion openings of the room where the ap-
pliance is installed, if present.
–Remove the mains power and gas supply
from the appliance if the external tem-
perature could fall below ZERO (risk of
freezing).
–To leave containers with flammable sub-
stances in the room where the appliance
is installed.
–To dispose of the packaging material irre-
sponsibly as it could be dangerous. Pack-
aging must be disposed of as specified
by the legislation in force in the country
where the appliance will be used.

5
RANGE
MODEL CODE
MURELLE.HT 25 T (Methane) 8115111
MURELLE.HT 35 T (Methane) 8115113
MURELLE.HT 25 T (GPL) 8115116
MURELLE.HT 35 T (GPL) 8115118
COMPLIANCE
Our company declares that MURELLE.HT T boilers comply with the
following directives:
–Gas Appliances EU Regulation 2016/426
–Boiler Efficiency Directive 92/42/EEC
–Low Voltage Directive 2014/35/EU
–Electromagnetic Compatibility Directive 2014/30/EU
–Ecodesign Directive 2009/125/EC
–Regulation (EU) No. 811/2013 - 813/2013
–Energy labelling Regulation (EU) No. 2017/1369
Please refer to the technical data plate for the serial number and
year of manufacture.
SYMBOLS
a
WARNING
To indicate actions which, if not carried out correctly, can
result in injury of a general nature or may damage or
cause the appliance to malfunction; these actions there-
fore require particular caution and adequate preparation.
f
ELECTRICAL HAZARD
To indicate actions which, if not carried out correctly, could
lead to injury of an electrical nature; these actions there-
fore require particular caution and adequate preparation.
d
IT IS FORBIDDEN
To indicate actions which MUST NOT BE carried out.
m
CAUTION
To indicate particularly important and useful information.
MANUAL STRUCTURE
This manual is organized as follows.
USER INSTRUCTIONS
TABLE OF CONTENTS 7
DESCRIPTION OF THE APPLIANCE
TABLE OF CONTENTS 15
INSTALLATION AND SERVICING
INSTRUCTIONS
TABLE OF CONTENTS 25

6

7
USER INSTRUCTIONS
TABLE OF CONTENTS
1USING THE BOILER MURELLE.HT T 8
1.1 Control panel ...................................8
1.2 Start-up .......................................9
1.2.1 Preliminary checks..................... 9
1.2.2 Ignition............................... 9
1.3 Settings using the MODE function .................10
1.4 Fault warnings .................................11
1.5 Time Programming .............................11
2SHUTDOWN 12
2.1 Temporary shutdown............................12
2.2 Shutting down for long periods ...................12
3MAINTENANCE 13
3.1 Adjustments...................................13
3.2 External cleaning...............................13
3.2.1 Cleaning the cladding.................. 13
4DISPOSAL 13
4.1 Disposal of the equipment (European Directive
2012/19/EU) ...................................13

8
1 USING THE BOILER MURELLE.HT T
1.1 Control panel
Menu ZonaModo
25
25
0
10 B12 11 C
43 5 6 7 8 9 A
25
1 2
13
14
2
15
1
16
20
1517
1918
1718
16
1521 22
23
Fig. 1
A“ESC” button: go back to the previous screen
LOCKOUT NOTIFICATION: when the boiler is locked, the button
lights up red
BMULTI-FUNCTION ENCODER: turn to navigate the menu, press
to confirm the selection
CDISPLAY
1
WiFi
2 Alarm symbol
3 Remote control, where relevant
4 Solar manifold temperature
5 DHW temperature
6 Date
7 Boiler delivery temperature
8 Room humidity level
9 Time
10 System pressure
11 Measured outdoor temperature
12 Presence of external sensor (SE)
13 Heating circuit “1” heat request active
14 Heating circuit “2” heat request active
15 Burner active
16 Burner modulation percentage
17 Domestic hot water circuit heat request active
18 Heat pump request in cold mode active
19 Heat pump active
20 Heat pump modulation percentage
21 Chimney sweep function active
22 Chimney sweep function modulation percentage
23 Programming connector
m
CAUTION
Remove the protective film on the display after the appli-
ance is used for the first time.

9
1.2 Start-up
1.2.1 Preliminary checks
a
WARNING
–Should it be necessary to access the areas in the bot-
tom part of the appliance, make sure that the system
components and pipes are not hot (risk of burning).
–Before replenishing the heating system, put on protec-
tive gloves.
Commissioning of the
MURELLE.HT T boiler must be carried out by
professionally qualified Personnel after which the boiler can operate
automatically. It may however be necessary for the User to start the
appliance autonomously without involving a technician: for example,
after a holiday . In these cases certain checks and the following op-
erations must be carried:
–check that the gas isolation and water system valves are open
–using a pressure gauge (1), check that the heating system pres-
sure when cold is 1-1.2 bar . If this is not the case, open the filling
valve, which is to be prearranged on the system return, and re-
store the heating system pressure until the pressure gauge (1)
shows a reading of 1-1.2 bar
–close the filling valve.
1
Fig. 2
1.2.2 Ignition
After having carried out the preliminary checks, perform the follow-
ing to start the boiler:
–set the main system switch to "ON"
–after a few seconds, the “Main screen” is shown
ON
Menu Mode Zones
Mon 01.01.2018 10:30
Fig. 3
–turn the encoder to select the “Mode” (Mode) function
–press the
click
encoder to go to the screen to select the “ Func-
tion mode”
(MODE). Turn the encoder to select the pre-
ferred mode e.g. “Winter” (Winter)
–press the
click
encoder to confirm “Winter” (Winter)
–press the “ESC” button to go back to the “main screen”.
Summer Winter Off
Hot water MAN 40
°C
Heating
Esc
Menu Mode Zones
<<strdata>> 10:30
Fig. 4
–open one or more of the hot water valves and check that the ap-
pliance starts up
Summer Winter Off
Hot water MAN 40
°C
Heating
Esc
Fig. 5
–allow the appliance to operate until hot water is produced and
shut off the valves opened previously.

10
1.3 Settings using the MODE function
From the “Main screen”:
Menu Mode Zones
Mon 01.01.2018 10:30
Fig. 6
–turn the encoder to select the “Mode” (Mode) function
–press the
click
encoder to go to the screen to select the “ Func-
tion mode”
(MODE). Turn the encoder to select the pre-
ferred mode e.g. “Winter” (Winter)
Summer Winter Off
Hot water MAN 40
°C
Heating
Esc
Fig. 7
–press the
click
encoder to confirm the highlighted “Mode” and
go to the “rows”
Summer Winter Off
Hot water MAN 40
°C
Heating
Esc
Fig. 8
–turn the encoder to select “Heating” (Heating)
–press the
click
encoder to confirm “Heating” (Heating) and
open the submenu
“Zone” (Zones)
Heating
Zone 1 [...]
Zone 2 [...]
Summer Winter Off
Hot water MAN 40
°C
Heating
Esc
Fig. 9
–turn the encoder to select the desired zone e.g. Zone 1
(Zone 1) or Zone 2 (Zone 2)
–press the
click
encoder to confirm the highlighted zone and go
to the row
Zone 1
Information [...]
Settings [...]
Config [...]
Fig. 10
Turn the encoder until selecting the desired function, e.g.
Settings
Zone 1
Information [...]
Settings [...]
Config [...]
Fig. 11
–press the
click
encoder to confirm the selected submenu and
access the relevant data display
Room 1 - Settings
Function Mode AUTO
Set AUTO comfort 20.5°C
Set AUTO reduced 17.0°C
Set MAN 19.2°C
Program. Time [...]
Fig. 12
–press the
clic
k
encoder to confirm the highlighted “Row” and
access the modifiable area
Room 1 - Settings
Function Mode AUTO
Set AUTO comfort 20.5°C
Set AUTO reduced 17.0°C
Set MAN 19.2°C
Program. Time [...]
Fig. 13

11
–turn the encoder to modify the “Data/value” in the permit-
ted field (e.g. OFF - ECO - MAN - AUTO)
–press the
click
encoder to confirm any modifications made and
go back to the row “Function mode” (Function Mode).
m
CAUTION
For information on boiler time programming, see “Time
Programming”.
m
CAUTION
The settings described above must be done for both
zones.
1.4 Fault warnings
If a fault occurs, the screen “Anomaly in progress” (Fault in pro-
gress) will appear in place of the “main screen”. For the main fault
codes, a brief description and suggestions for the user are dis-
played, based on the seriousness and the frequency with which the
fault reappears.
Fault in progress
ALL 05 - Flow sensor fault
Esc
Fault in progress
Reset
ALL 06 - No flame detection
Fig. 14
The fault may be transient (volatile) or it may cause an appliance
block .
To restore normal operating conditions:
–if the fault is transient, eliminate the cause of the fault
–if the fault causes a block, eliminate the cause of the fault and
then press the
“RESET” (Reset) button; press the encoder
to confirm.
Fault in progress
ALL 02 - Low system water pressure
Fill
Fault in progress
Confirm operation
Confirm
Fig. 15
m
CAUTION
For a full list of faults, see "Malfunction codes and pos-
sible solutions".
1.5 Time Programming
The control panel allows up to a maximum of four daily time bands
to be managed for the domestic hot water function and the heating
function described below.
During the programmed time band, the boiler works in COMFORT
heating mode, while outside the programmed time band it works in
REDUCED heating mode:
–press the
clic
k
encoder to confirm the “Program. time” and go
to the modifiable area
Confirm
Heating Time Program
0246 81 01 21 41 61 82 02 22 4
[1] 06:00 - 08:00
[2] 11:00 - 13:00
[3] -
[4] 18:00 - 23:00
MondayDay/s
Fig. 16
–turn the encoder to select the “Single days” or the “Group
of days”
–press the
click
encoder to confirm the required selection and
access the first “Adjustable time” [1]
Heating Time Program
0246 81 01 21 41 61 82 02 22 4
[1] 06:00 - 08:00
[2] 11:00 - 13:00
[3] -
[4] 18:00 - 23:00
MondayDay/s
Confirm
Fig. 17
–turn the encoder to modify the “Data/value” on the basis
of the required time
–press the
click
encoder to confirm the modification and move
to the next “Data/value”
Heating Time Program
0246 81 01 21 41 61 82 02 22 4
[1] 06:00 - 08:00
[2] 11:00 - 13:00
[3] -
[4] 18:00 - 23:00
MondayDay/s
Confirm
Fig. 18
–continue in this way until all the necessary modifications have
been made for each day of the week or group of days.
NOTE : The user must work in a CIRCULAR manner, meaning AL-
WAYS MOVING FORWARDS, even if a mistake is made.

12
m
CAUTION
If NO time band is required, set the start and stop times of
that band to the same value (e.g. [3] 14:00-14:00).
–When all modifications have been made, turn the encoder
to select
“Confirm” (Confirm) and press the
click
encoder to go
back to “Single days” or “Groups of days”
–press the
“ESC” button to go back to the “main screen”.
Menu Mode Zones
Mon 01.01.2018 10:30
Fig. 19
2SHUTDOWN
2.1 Temporary shutdown
If the user wishes to interrupt boiler operation temporarily:
–turn the encoder to select the
“Mode” (Mode) function
–press the
click
encoder to go to the screen to select the “ Func-
tion mode”
(MODE). Turn the encoder to select “OFF”
–press the
click
encoder to switch the boiler off.
Summer Winter Off
Hot water MAN 40
°C
Heating
Esc
Fig. 20
f
ELECTRICAL HAZARD
The boiler will still be powered.
–set the main system switch to "OFF"
–close the gas valve.
If the user is away temporarily, for a weekend, short trip etc and if
the outside temperature is at ZERO:
OFF
Fig. 21
2.2 Shutting down for long periods
If the boiler is to be left unused for a long period, the following oper-
ations need to be carried out:
–switch off the boiler as specified in the “Temporary shutdown”
section
–set the main system switch to "OFF"
OFF
Fig. 22
–close the gas valve
–close the heating and domestic hot water isolation valves
–drain the heating and domestic hot water system if there is the
risk of freezing.
m
CAUTION
Contact the Qualified Technical Personnel if the proce-
dure described above cannot be easily carried out.

13
3MAINTENANCE
3.1 Adjustments
For the appliance to operate correctly and efficiently it is recom-
mended that the User calls upon the services of a Professionally
Qualified Technician to carry out
ANNUAL maintenance.
m
CAUTION
Maintenance interventions must ONLY be carried out by
professionally qualified personnel who will follow the
indications provided in the INSTALLATION AND MAINTE-
NANCE MANUAL.
3.2 External cleaning
a
WARNING
–Should it be necessary to access the areas in the bot-
tom part of the appliance, make sure that the system
components and pipes are not hot (risk of burning).
–Before performing any maintenance, put on protective
gloves.
3.2.1 Cleaning the cladding
When cleaning the cladding, use a cloth dampened with soap and
water or alcohol for stubborn marks.
d
IT IS FORBIDDEN
to use abrasive products.
4DISPOSAL
4.1 Disposal of the equipment (European Direc-
tive 2012/19/EU)
d
IT IS FORBIDDEN
dispose of the product with urban waste.
At the end of their life span, the appliance and
electrical and electronic devices coming from
households or classifiable as household waste
must be delivered to appropriate waste collection
systems, in accordance with the law and with Di-
rective 2012/19/EU. This product was designed
and manufactured for minimising its impact on the
environment and on human health, but it contains
components that could be detrimental if managed
improperly. The symbol (crossed-out wheelie bin)
depicted here and also appearing on your appli-
ance means that the appliance at the end of its life
must be managed in accordance with the law and
treated as electrical and electronic waste. Before
delivering the appliance for its disposal, consult
the applicable provisions of the laws in force in the
country where the appliance is used and get infor-
mation on the authorised waste disposal facilities
by contacting the relevant local offices.

14

15
DESCRIPTION OF THE APPLIANCE
TABLE OF CONTENTS
5DESCRIPTION OF THE APPLIANCE 16
5.1 Characteristics ................................16
5.2 Check and safety devices ........................16
5.3 Identification ..................................16
5.3.1 Technical Data Plate................... 17
5.4 Structure .....................................18
5.5 Technical features ..............................19
5.6 Main water circuit ..............................20
5.7 Sensors.......................................20
5.8 Expansion vessel ...............................21
5.9 Circulation pump ...............................21
5.10 Control panel ..................................22
5.11 Wiring diagram ................................23

16
5 DESCRIPTION OF THE APPLIANCE
5.1 Characteristics
MURELLE.HT T are last generation condensing wall mounted boil-
ers which Sime has produced for heating and domestic hot water
production when combined with a storage tank. The main design
choices made by Sime for the MURELLE.HT T boilers are:
– the total pre-mix microflame burner combined with a steel heat
exchanger for heating
– the sealed combustion chamber which can be classified "Type C"
or "Type B" in relation to the room where the boiler is installed,
depending on the smoke outlet configuration adopted during in-
stallation
– the command and control microprocessor electronic board pro-
vides efficient management of both heating and hot water pro-
duction. It can also be connected to a remote control with an Open
Therm protocol or to room thermostat and/or external sensor. If
connected to an external sensor, the boiler temperature varies
on the basis of the external temperature according to a selected
optimal climatic curve providing significant energy and economic
savings.
Other special features of the
MURELLE.HT T boilers are:
– the anti-freeze function which activates automatically if the tem-
perature of the water inside the boiler falls below the value set
under parameter "PAR 7" and, where there is an external sensor,
if the external temperature falls below the value set under pa-
rameter "PAR 8"
– the anti-blocking function of the pump and diverter valve, this
activates automatically every 24 hours if no request for heat has
been made
– the chimney sweep function lasts 15 minutes and makes the job
of the qualified technician easier when measuring the parame-
ters and combustion efficiency
– screen display of the operating and self-diagnostic parameters
with error code display when the fault occurs. This makes repair
interventions easier and allows appliance operation to be re-
stored correctly.
5.2 Check and safety devices
The MURELLE.HT T boilers are equipped with the following check
and safety devices:
– thermal safety thermostat 100°C
– 3 bar relief valve
– heating water pressure transducer
– delivery sensor
– return sensor
– hot water tank sensor
– smoke flue gas probe.
d
IT IS FORBIDDEN
To commission the appliance with safety devices which do
not work or which have been tampered with.
a
WARNING
Safety device may only be replaced by professional quali-
fied personnel using Sime original spare parts.
5.3 Identification
The MURELLE.HT T boilers can be identified by means of:
1 Packaging label: this is located on the outside of the packaging
and provides a code, the serial number of the boiler and the bar
code.
2 Energy Efficiency Label: this is positioned on the outside of the
packaging to notify the User of the level of energy savings and
reduced environmental pollution produced by the appliance.
3 Technical Data Plate: this is located inside the front panel of the
boiler and provides the technical data, appliance performance
information and any other information required by law in the
country where the appliance will be used.
1
3
1
I II
A
B
C
D
E
F
G
2015 811/2013
Cod. 6244745
dB kW
A++
A+
A
B
C
D
E
F
G
2
2
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

       
       

         
 
 
 

  








 






 
  
   
 
   
   


 


 
 
 

  
  
  

 

 
 

 
 

 

 
 
3
Fig. 23

17
5.3.1 Technical Data Plate


 




 











       
       

         
 
 
 

 








 






 
 
   
 
   
   


 


 
 
 

  
  
  

 

 
 

 


 

 
 
YEAR OF MANUFACTURE
SERIAL NUMBER
NAME
MAX USEFUL OUTPUT (50-30°C)
MAX OPERATING PRESSURE
MAX USEFUL OUTPUT (80-60°C)
MAX HEAT INPUT
WATER CONTENT IN BOILER
TYPE OF GAS
CODE
APPLIANCE TYPE
MAX OPERATING TEMPERATURE
MIN USEFUL INPUT (50-30°C)
MAX D.H.W. TEMPERATURE
MIN HEAT INPUT
MIN USEFUL OUTPUT (80-60°C)
APPLIANCE CLASSIFICATION
TYPE OF GAS
SUPPLY PRESSURE
MIN HEAT INPUT
NOx CLASS
GAS COUNCIL NUMBER CODE (UK)
WRAS CERTIFICATION (UK)
ELECTRICAL PROTECTION DEGREE
N° PIN
TYPE OF GAS
TYPE OF GAS
TYPE OF GAS
FLOW RATE
MAX OPERATING PRESSURE
ELECTRICAL SUPPLY
MAXIMUM ABSORBED POWER
MAX HEAT INPUT
COUNTRY OF INTENDED INSTALLTION
APPLIANCE CATEGORY
D.H.W. CONTENT
Fig. 24
m
CAUTION
Tampering with, removing or failing to display the identification plate or carrying out any other operation which does not allow safe
identification of the product or which may hinder installation and maintenance operations.

18
5.4 Structure
20
21
22
23
24
25
15
30 26272829
1
2
3
4
5
6
10
11
12
13 14
17
18
19
16
8
7
9
1 Heat exchanger bleed point
2 Heat exchanger
3 Combustion chamber door
4 Oversleeve
5 Flame viewing window
6 Ignition/detection electrode
7 Return sensor (SR)
8 Heat safety thermostat
9 Delivery sensor
10 Condensate siphon
11 Diverter valve
12 System filling unit
13 Control panel
14 Gas valve
15 Tap fittings cover
16 System relief valve
17 Boiler drain
18 System pump
19 Water pressure transducer
20 Automatic bleed valve
21 Fan
22 Air-gas mixer
23 Expansion vessel
24 Air inlet pipe
25 Air-smoke chamber
26 Air inlet
27 Air inlet analysis take-off point
28 Smoke outlet
29 Take-off point for smoke analysis
30 Smoke flue gas probe
Fig. 25

19
5.5 Technical features
DESCRIPTION
MURELLE.HT T
25 35
CERTIFICATIONS
Country of intended installation IT - ES - PT - EN - FR - DE - NL - CZ - RU
Fuel G20 / G31
PIN number 1312CS6249
Category II2H3P
Appliance classification B23P - B53P - C(10)3 - C13 - C33 - C43 - C53 - C83 - C93
Class NO
x (*) 6 (< 56 mg/kWh)
DHW rated useful heat output kW 0
HEATING PERFORMANCE
HEAT INPUT (**)
Nominal flow (Q
n max) kW 24,5 34,5
Minimum flow G20/G31 (Q
n min) kW 1,75 / 3,5 2,5 / 6,0
HEAT OUTPUT
Nominal useful output G20/G31 (80-60°C) (P
n max) kW 24,2 33,9
Nominal useful output G20/G31 (50-30°C) (P
n max) kW 26,4 37,2
Minimum G20 (80-60°C) (P
n min) kW 1,65 2,33
Minimum G20 (50-30°C) (P
n min) kW 1,81 2,60
Minimum G31 (80-60°C) (P
n min) kW 3,30 5,60
Minimum G31 (50-30°C) (P
n min) kW 3,62 6,19
EFFICIENCY
Max useful efficiency (80-60°C) %98,7 98,2
Min useful efficiency (80-60°C) %94,3 93,3
Max useful efficiency (50-30°C) %107,9 107,7
Min useful efficiency (50-30°C) %103,4 103,2
Useful efficiency at 30% of load %108,6 108,6
Losses after shutdown at 50°C W95,0 113
ENERGY PERFORMANCE
HEATING
Heating seasonal energy efficiency class A A
Heating seasonal energy efficiency %93 93
Sound power dB(A) 51 53
ELECTRICAL SPECIFICATIONS
Power supply voltage V230 230
Frequency Hz 50 50
Absorbed electrical power (Q
n max) W89 105
Absorbed electrical power at (Q
n min) W61 64
Absorbed electrical power in stand-by W 5 5
Electrical protection degree IP X5D X5D
COMBUSTION DATA
Smoke temperature at Max/Min flow (80-60°C) °C 79,9 / 68,4 79,4 / 62,3
Smoke temperature at Max/Min flow (50-30°C) °C 56,4 / 52,8 58,1 / 51,8
Smoke flow Max/Min g/s 11,5 / 0,9 15,9 / 1,2
CO
2 at Max/Min flow rate (G20) %9,3 / 8,8 9,5 / 9,0
CO
2 at Max/Min flow rate (G31) %10,0 /10,0 10,3 / 10,3
NOx measured mg/kWh 38 45
NOZZLES  GAS
Number of nozzles No. 2 2
Nozzle diameter (G20-G31) mm 3,3 / 2,6 - 2,6 / 1,9 4,0 / 3,5 - 3,0 / 2,8
Gas consumption at Max/Min flow rate (G20) m
3
/h 2,59 / 0,185 3,65 / 0,26
Gas consumption at Max/Min flow rate (G31) kg/h 1,90 / 0,27 2,68 / 0,47
Gas supply pressure (G20/G31) mbar 20 / 37 20 / 37
kPa 2 / 3,7 2 / 3,7
(*) NOx class according to UNI EN 15502-1:2021
(**) Heat input calculated using the lower heat output (Hi)
Lower Heat Output (Hi)
G20 Hi. 9.45 kW/m
3
(15°C, 1013 mbar) - G31 Hi. 12.87 kW/kg (15°C, 1013 mbar)

20
DESCRIPTION
MURELLE.HT T
25 35
TEMPERATURE  PRESSURE
Max operating temperature (T max) °C 85
Heating adjustment range °C 20÷80
Domestic hot water adjustment range °C 10÷60
Max operating pressure (PMS) bar 3
kPa 300
Water content in boiler l4,9 6,0
Lower Heat Output (Hi)
G20 Hi. 9.45 kW/m
3
(15°C, 1013 mbar) - G31 Hi. 12.87 kW/kg (15°C, 1013 mbar)
NOTE: if the appliance is to operate in combination with a storage tank, the Heat Input remains unchanged in relation to the HEATING PER-
FORMANCE.
5.6 Main water circuit
3
5
6
12 13 14
15
17
18
19
20
21
22
23
9
8
7
10
16
11
M
U
G
E
R
Sc
S
To be carried
out by the installer
2
1
RbMb
4
Fig. 26
KEY:
MSystem delivery
RSystem return
Mb Hot water tank delivery
Rb Hot water tank return
SSafety valve outlet
GGas supply
UDomestic hot water outlet
EDomesti hot water inlet
Sc Condensate outlet
1 Condensing heat exchanger
2 Combustion chamber
3 Fan
4 Return sensor (SR)
5 Thermal safety thermostat
6 Delivery sensor
7 Pressure transducer
8 Automatic bleed valve
9 Pump
10 System expansion vessel
11 Diverter valve
12 Automatic by-pass
13 Gas valve
14 Boiler drain
15 System relief valve
16 Condensate siphon outlet
17 Storage tank
18 Magnesium anode
19 Domestic hot water sensor
20 Hot water tank drain valve
21 Domestic hot water expansion vessel
22 Hot water tank relief valve
23 Domestic hot water inlet valve
5.7 Sensors
The sensors installed have the following characteristics:
–Dual sensor (thermal safety/output) NTC R25°C; 10kΩ β25°-85°C:
3435
–domestic hot water sensor NTC R25°C; 10kΩ β25°-85°C: 3435
–External temperature sensor NTC R25°C; 10kΩ β25°-85°C: 3435
TR
0°C 1°C 2°C 3°C 4°C 5°C 6°C 7°C 8°C 9°C
Resistance R (Ω)
0°C 27279
17959
12090
8313
5828
4161
3021
2229
1669
1266
973
26135
17245
11634
8016
5630
4026
2928
2164
1622
1232
25044
16563
11199
7731
5440
3897
2839
2101
1577
1199
24004
15912
10781
7458
5258
3773
2753
2040
1534
1168
23014
15289
10382
7196
5082
3653
2669
1982
1491
1137
22069
14694
9999
6944
4913
3538
2589
1925
1451
1108
21168
14126
9633
6702
4751
3426
2512
1870
1411
1079
20309
13582
9281
6470
4595
3319
2437
1817
1373
1051
19489
13062
8945
6247
4444
3216
2365
1766
1336
1024
18706
12565
8622
6033
4300
3116
2296
1717
1300
998
10°C
20°C
30°C
40°C
50°C
60°C
70°C
80°C
90°C
100°C
Correspondence of Temperature Detected/Resistance
Examples of reading:
TR=75°C → R=1925Ω
TR=80°C → R=1669Ω.