Baxi LUNA HT 1.280 User manual

Wall-mounted condensing boilers
Installer’s and User’s Instructions
UNI EN ISO 9001
CERTIFICAZIONE DEI SISTEMI
QUALITA' DELLE AZIENDE
HT
BAXI S.p.A., one of the leading European enterprises to produce central heating and hot water devices for domestic use (wall-mounted gas-operated
boilers, floor-standing boilers and electrical water-heaters) has obtained the CSQ certificate of conformity to the UNI EN ISO 9001 norms. This
certificate guarantees that the Quality System applied at the BAXI S.p.A. factory in Bassano del Grappa, where your boiler was produced, meets
the standards of the UNI EN ISO 9001 norm, which is the strictest and concerns all organization stages and operating personnel involved in the
production and distribution processes.
0085

Dear Customer,
We are sure your new boiler will comply with all your requirements.
Purchasing one of the BAXI products satisfies your expectations: good
functioning, simplicity and ease of use.
Do not dispose of this booklet without reading it: you can find here some
very useful information, which will help you to run your boiler correctly
and efficiently
.
Do not leave any parts of the packaging (plastic bags, polystyrene, etc.) within childrenʼs reach as
they are a potential source of danger.
BAXI boilers bear the CE mark in compliance with the basic requirements as laid down
in the following Directives:
- Gas Directive 90/396/CEE
- Performance Directive 92/42/CEE
- Electromagnetic Compatibility Directive 89/336/CEE
- Low Voltage Directive 73/23/CEE

Contents
1. Instructions prior to installation 4
2. Instructions prior to commissioning 4
3. Commissioning of the boiler 5
4. Filling the boiler 10
5. Turning off the boiler 10
6. Prolonged standstill of the system. Frost protection 11
7. Gas change 11
8. Servicing instructions 11
Instructions pertaining
to the user
9. General information 12
10. Instructions prior to installation 12
11. Boiler installation 13
12. Boiler size 13
13. Fittings present in the packaging 14
14. Installation of flue and air ducts 14
15. Connecting the mains supply 18
16. Gas change modalities 24
17. Setting the boiler parameters 27
18. Control and operation devices 28
19. Positioning of the ignition and flame sensing electrode 29
20. Check of combustion parameters 29
21. Activating the flue-sweeper function 29
22. Output / pump head performances 30
23. How to disassemble the DHW heat exchanger 30
24. Cleaning the cold water filter 31
25. Annual service 31
26. Boiler schematic 32-33
27. Illustrated wiring diagram 34-35
28. Technical data 36
Instructions pertaining
to the installer

4
Instructions pertaining to the user
2. Instructions prior to
commissioning
Initial lighting of the boiler must be carried out by a licensed technician. Ensure the following ope-
rations are carried out:
a) compliance of boiler parameters with (electricity, water, gas) supply systems settings.
b) compliance of installation with the laws and regulations in force.
c) appropriate connection to the power supply and grounding of the appliance.
The names of authorized Service Centres are listed on the accompanying sheet.
Failure to observe the above will render the guarantee null and void.
Prior to commissioning remove the protective plastic coating from the unit. Do not use any tools or
abrasive detergents as you may spoil the painted surfaces.
This boiler is designed to heat water at a lower than boiling temperature at atmospheric pressure.
The boiler must be connected to a central heating system and to a domestic hot water supply system
in compliance with its performances and output power.
Have the boiler installed by a Qualified Service Engineer and ensure the following operations are
accomplished:
a) careful checking that the boiler is fit for operation with the type of gas available. For more details
see the notice on the packaging and the label on the appliance itself.
b) careful checking that the flue terminal draft is appropriate; that the terminal is not obstructed and
that no other appliance exhaust gases are expelled through the same flue duct, unless the flue is
especially designed to collect the exhaust gas coming from more than one appliance, in conformity
with the laws and regulations in force.
c) careful checking that, in case the flue has been connected to pre-existing flue ducts, thorough
cleaning has been carried out in that residual combustion products may come off during operation
of the boiler and obstruct the flue duct.
d) to ensure correct operation of the appliance and avoid invalidating the guarantee, observe the
following precautions:
1. Hot water circuit:
1.1. If the water hardness is greater than 20 °F (1 °F = 10 mg calcium carbonate per litre of water)
a polyphosphate or comparable treatment system responding to current regulations.
1.2. Domestic Hot Water circuit must be thoroughly flushed after the installation of the appliance
and before its use.
2. Heating circuit
2.1. new system
Before proceeding with installation of the boiler, the system must be cleaned and flushed
out thoroughly to eliminate residual thread-cutting swarf, solder and solvents if any, using
suitable proprietary products.
To avoid damaging metal, plastic and rubber parts, use only neutral cleaners, i.e. non-acid
and non alkaline. The recommended products for cleaning are:
SENTINEL X300 or X400 and FERNOX heating circuit restore. To use this product proceeding
strictly in accordance with the makerʼs directions.
2.2. existing system
Before proceeding with installation of the boiler, the system must be cleaned and flushed
out to remove sludge and contaminants, using suitable proprietary products as described in
section 2.1.
To avoid damaging metal, plastic and rubber parts, use only neutral cleaners, i.e. non-acid
and non-alkaline such as SENTINEL X100 and FERNOX heating circuit protective. To use
this product proceeding strictly in accordance with the makerʼs directions.
Remember that the presence of foreign matter in the heating system can adversely affect the
operation of the boiler (e.g. overheating and noisy operation of the heat exchanger).
Failure to observe the above will render the guarantee null and void.
1. Instructions prior to
installation

5
3-1. Description of keys
(2) This key can be pressed to set the central heating water output temperature as described
in point 3-3.
(3) This key can be pressed to set the domestic hot water temperature as described in point 3-4.
(10) Central heating mode operating key
The key can be pressed to activate four boiler central heating operating modes; these
modes are identified by a black cursor line underneath the relative symbol on the display,
and are as follows:
KEYS DISPLAY SYMBOLS
Central heating mode setting key
Data display reset key
Parameter setting key (increase value)
Parameter setting key (decrease value)
Program access and scroll key
Program access and scroll keys
Reset key
Domestic hot water temperature setting
key
Central heating water temperature setting
key
Domestic hot water on/off key
Resettable alarm warning
Flame present (on)
Outdoor temperature
Standby (off)
Operation in manual mode at minimum
temperature
Operation in manual mode at the maxi-
mum temperature set
Operation in automatic mode
Operation in central heating mode
Operation in domestic hot water mode
020503_1100
Figure 1
SECONDARY display
MAIN display
To correctly light the burner proceed as follows:
1) provide power supply to the boiler;
2) open the gas cock;
3) follow the directions given below regarding the adjustments to be made at the boiler control panel.
3. Commissioning of the
boiler

6
020503_0800
Figure 2
a) Automatic operation. Operation of the boiler is controlled by the timed program as described
in point 3-5.1 “Daily timed program for operation of the central heating system”;
b) Manual operation at the maximum temperature set. The boiler comes into operation
regardless of the timed program set. The operating temperature is that set using the key
(point 3-3: “Setting the maximum central heating temperature”);
c) Manual operation at minimum temperature. The operating temperature is that set in
point 3-6: “setting the minimum central heating temperature”.
d) standby. The boiler does not work in central heating mode, although the antifreeze function
is still enabled.
(1) Domestic hot water on/off key: This key can be pressed to activate or deactivate this
function, which is identified on the display by a black cursor line under the symbol .
(4) Reset key. In case of a fault, referred to in point 3-7 “Faults and resetting the boiler”,
the boiler can be restarted by pressing this key for at least two seconds.
If this key is pressed with no fault present, the display will show the message “E153”, and
the same key has to be pressed again (for at least two seconds) to restart the boiler.
(9) Data key. This key can be pressed repeatedly to display the following information:
- Temperature (°C) of the domestic hot water ( );
- outdoor temperature (°C) ( ); only provided with the outdoor temperature sensor probe
connected.
Press either of the keys to return to the main menu.
3-2. Setting the time
a) Press either of the keys to access the programming function;
the display will show the letter P followed by a number (program line);
020503_0700
Figure 3
Dash
“Automatic mode”
active
b) press the keys until the display shows P1, referring to the time to be set;
c) press the keys to set the time; on the display, the letter P will start to flash;
d) press the key to save and exit the programming function;

7
3-3. Setting the maximum central heating temperature
- Press the key (2-figure 1) to set the central heating water temperature;
- Press the keys to set the temperature required;
- press either of the keys (1 or 10 - figure 1) to save and return to the main menu.
N.b – With the outdoor sensor probe connected, the key (2 - figure 1) can be used to shift the
central heating curve. Press the keys to decrease or increase the room temperature in the
premises to be heated.
3-4. Setting the maximum domestic hot water temperature
- Press the key (3-figure 1) to set the maximum domestic hot water temperature;
- Press the keys to set the temperature required;
- press either of the keys (1 or 10 - figure 1) to save and return to the main menu.
3-5. Setting the daily program for operation in central heating and domestic hot water modes
3-5.1. Setting the daily times for central heating mode operation
- Press either of the keys to access the programming function;
a) press these keys until the display shows P11, referring to the program start time;
b) press the keys to set the time;
- press the key; the display will show P12, referring to the program end time;
- repeat the operations described in points a and b until the third and last cycle is reached
(program line P16);
- press the key to save and exit from the programming function.
3-5.2. Setting the daily times for domestic hot water mode operation
- Carry out the operations described in point 3-5.1 for program lines 31 to 36.
3-6. Setting the minimum central heating temperature
- press either of the keys to access the programming function;
- press these keys until the display shows P5, referring to the temperature to be set;
- press the keys to set the temperature required.
This operating mode is enabled when minimum temperature central heating mode is activated or
when the daily central heating program does not require heat.
N.b – With the outdoor sensor probe connected, parameter P5 can be used to set the minimum
room temperature in the premises to be heated.

8
3-8. Fault warnings and resetting the boiler
If a fault occurs, a flashing warning code appears on the display.
The fault warnings appear on the main display (figure 1 a) together with the symbol (Figure 4).
To reset, press the reset button for at least two seconds.
3-7. Table of user-settable parameters
020503_0500
Figure 4
Note: Parameters from P31 to P36 can be displayed only if the domestic hot water program has been
enabled as described in chapter 17 for the attention of the installer (parameter H91).
Range
0…23:59
25..80
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
00:00…24:00
0...1
Factory
setting
———-
25
6:00
22:00
0:00
0:00
0:00
0:00
0:00
24:00
0:00
0:00
0:00
0:00
0
Parameter description
Time of day setting
Minimum central heating temperature setting (°C)
Start of first daily period of automatic central heating
End of first daily period of automatic central heating
Start of second daily period of automatic central heating
End of second daily period of automatic central heating
Start of third daily period of automatic heating
End of third daily period of automatic central heating
Start of first daily period of domestic hot water production
End of first daily period of domestic hot water production
Start of second daily period of domestic hot water production
End of second daily period of domestic hot water production
Start of third daily period of domestic hot water production
Fine End of third daily period of domestic hot water production
Reset of daily central heating and domestic hot water production programs (factory
settings). Press the - + keys together for about 3 seconds; the number 1 appears on
the display. Confirm by pressing either of the keys
Parameter
N.
P1
P5
P11
P12
P13
P14
P15
P16
P31
P32
P33
P34
P35
P36
P45

9
0510_2701
Figure 4.1
Fault warnings appear on the secondary display (figure 1 b) alternating with the time, both of them
flashing (figure 4.1). It is not possible to reset malfunction warnings which appear on the secondary
display as the cause of the alarm has first to be removed.
All the faults are displayed in order of importance; if several faults occur simultaneously, the first to
be displayed is the one with highest priority. After the cause of the first fault has been removed, the
second one will be displayed, and so on.
If any given fault occurs frequently, contact the authorised Service Centre.
action required
call the authorised service centre.
call the authorised service centre.
call the authorised service centre.
press the reset key (for about 2 seconds: if this device is triggered
repeatedly, call the authorised service centre)
call the authorised service centre.
call the authorised service centre.
call the authorised service centre.
press the reset key (for about 2 seconds); if the fault persists, call the
authorised service centre)
switch off the electricity supply to the boiler for 10 seconds; if the fault
persists, call the authorised service centre)
press the key again (about 2 seconds)
Press and hold reset button (2 seconds approx.) then press again when
warning E153 appears
call the authorised service centre.
check that the system is at the rated pressure. (refer to the section on filling
the system). if the fault persists, call the authorised service centre.
Fault description
outdoor temperature probe sensor failure
ntc output sensor failure
domestic hot water ntc sensor failure
safety or flue gas thermostat tripped
loss of flame during operation (the ionization
current has fallen below the limit)
minimum fan speed limit is hurt
floor thermostat tripped
no gas
boiler circuit board error
the reset key has been pressed
inappropriately
internal error on boiler circuit module
fan speed threshold not reached
no hydraulic differential pressure
switch enabling signal
3-9. Fault warnings table
Fault
code
E10
E20
E50
E110
E128
E129
E132
E133
E151
E153
E154
E160
E164

10
To shut down the boiler switch off the electrical supply to the appliance.5. Turning off the boiler
The boiler is equipped with a hydraulic differential pressure switch that will inhibit the operation of
the boiler in the event of the pump seizing or running dry.
Important: Regularly check that the pressure displayed by the manometer (11 - Figure 20) is 1 to 1.5
bar, with boiler not operating. In case of overpressure, open the boiler drain valve.
In case the pressure is lower open the boiler filling tap (Figure 5a or 5b).
We recommend you open the tap very slowly in order to let off the air.
In case pressure drops occur frequently have the boiler checked by a Qualified Service Engineer.
4. Filling the boiler
020503_0400
Boiler filling tap Boiler drain valve
Figure 5a
LUNA HT 280 - HT 330
0010270500
Figure 5b
LUNA HT 1.120 - HT 1.240 - HT 1.280
Boiler filling tap