Baxi Luna Duo-Tec Operating instructions

LUNA DUO-TEC
Troubleshooting

WARNING!
THIS DOCUMENT IS INTENDED ONLY AS AN
EDUCATIONAL TOOL
This Troubleshooting Guide, and the instructions and suggestions
within are intended solely as an educational tool assisting
completely qualified Gas Appliance Mechanics who have
successfully completed the Baxi Installation Certification Program.
Use of the information herein for the purposes of onsite appliance
correction by untrained personnel may cause extremely
dangerous conditions, and may void the manufacturer’s warranty.
Baxi N.A. assumes absolutely no liability in the execution of the
training suggestions in this document. Should you experience
problems or complications beyond your realm of training, please
contact Baxi N.A. for further instructions.

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
Table of Contents
Section
Page
Controller
2
Access
i
n
g
P
r
m
e
t
e
r
s
3
D
e
s
c
r
i
p
t
i
o
n
o
f
P
r
m
e
t
e
r
4
E
r
r
o
r
C
o
d
e
H
i
s
t
o
r
y
6
E
r
r
o
r
C
o
d
e
s
8
M
u
l
t
i
Z
o
n
e
R
e
l
y
C
r
d
C
o
n
n
e
c
t
i
o
n
n
d
O
p
t
i
o
n
s
1
7
P
C
B
R
e
p
l
c
e
m
e
n
t
(
without
e
s
y
k
e
y
s
e
r
v
i
c
e
M
e
m
o
r
y
s
t
i
c
k
)
1
8
P
C
B
R
e
p
l
c
e
m
e
n
t
(
w
i
t
h
e
s
y
k
e
y
s
e
r
v
i
c
e
)
1
9
C
o
m
b
u
s
t
i
o
n
A
d
j
u
s
t
m
e
n
t
F
u
n
c
t
i
on
(
3
0
4
)
2
1
M nu l C
ontrol F
unction (301)
2
1
D
e
-
e
r
t
i
o
n
F
u
n
c
t
i
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n
(
3
1
2
)
2
2
R
e
p
l
c
e
me
nt
P
r
t
s
2
2
P
r
e
s
s
u
r
e
T
b
l
e
2
3

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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CONTROLLER
SYMBOLS
Boiler Off – Heating and DHW
disabled
Boiler frost protection is active)
Burner on
Ignition Fault Domestic hot water mode
enabled
Boiler/system water pressure low Central Heating mode enabled
Error call for service Programming menu
Resettable fault Boiler information menu
Fault in progress Units of measure
BUTTONS
DHW temperature adjustment
(+ to incre se the temper ture nd – to decre se it)
CH temperature adjustment
(+ to incre se the temper ture nd – to decre se it)
Boiler operating information
Boiler Operating mode:
DHW only – DHW & He ting – He ting only
Off – Reset – Exit menu/functions

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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ACCESSING PARAMETERS
1) Press both the nd buttons fro 6 seconds, the displ y shows “P01”
ltern ting with its v lue 0);
2) Press either or buttons to scroll the p r meters list;
3) Press the button to edit the selected p r meter;
4) Press either or buttons to modify the p r meter v lue ;
5) Press the button to s ve the p r meter v lue, or press the button to exit the
function without s ving.
In the def ult condition it is possible to scroll through the p r meters until P42. If you need
to set some p r meters fter P42 proceed s follows:
-Press either or buttons until P22 is re ched;
-Press the button to edit the selected p r meter;
-Set P22 to 22;
-Press the button to s ve the p r meter v lue;
-Press either or button to scroll through the p r meters from P42 to P76

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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DESCRIPTION OF PARAMETERS
LUNA DUO-TEC
FACTORY SETTINGS
1.33 GA 40 GA
P01
-------
00
P02
Gas used
N tur l G s = 00
Prop ne = 01
00
P03
Hydraulic system
00 = inst nt neous ppli nce
03 = inst nt neous ppli nce with pre-he t function
05 = ppli nce with extern l stor ge boiler
08 = he ting only ppli nce
13 = inst nt neous ppli nce with pre-he t function
for sol r pplic tion
08 00
P04
Programmable relay 1 setting optional):
00 = no function is ssoci ted
01 = close cont ct with room thermost t request
02 = close cont ct with remote control request
03 = rel y for Low w ter in the system lerts
04 = rel y for Error code lerts
05 = rel y for kitchen f n function
07 = rel y for post circul tion pump
09 = DHW rel y on with DHW progr m setting
10 = DHW rel y on with DHW request; if P64 = 1
rel y on with CH nd DHW request
13 = rel y for Cooling function
14 = close cont ct with room thermost t request
with post circul tion
15 = close cont ct with remote control request
with post circul tion
02
P05
Programmable relay 2 setting optional):
(The s me configur tions s Rel y 1-P04) 04
P06
..P09
Manufacturer information
--
P10
Heating se
t
point setting OT / RT
Open Therm / Room Thermostat 120V~)
00= with Remote Control (RC) connected, the
temper ture request is the RC set point
01= The temper ture Request is the highest set
point between RC nd PCB
02 = The temper ture request is the RU set point.
The RT en ble the g s boiler oper tes
00
P11..P12
Manufacturer information
--
P13
Max. heating output 0
-
100%)
100
77
P14
DHW max. output 0
-
100%)
100
P1
5
Min. heating output 0
-
100%)
00

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
P16
Maximum CH setpoint °C)
00 = 176°F / 80°C - 01 = 113°F / 45°C 00
P17
Pump overrun t
ime in heating mode
(01-240 minutes) 03
P18
Burner ignition
pause time
in CH mode
(00-10 minutes) - 00=10 seconds 03
P19
Manufacturer information
07
P20
Pump overrun time in DHW mode seconds)
30
P21
Anti
-
legionellosis function
00 = Dis bled
01 = En bled
00
P22
Manufacturer information
(set “22” to displ y p r meters P71 nd P72) 00
P23
Maximum DHW setpoint temperature
(113°-140°F /45°-60°C) 49
P24
Manufacturer information
35
P25
No water safety device
00
P26..P31
Manufacturer information
--
P32..P41
Diagnostics See SERVICE Instructions
--
P44
Temperature unit setting
00 = °C
01 = °F
01
P71 *
Maximum fan speed
--
P72 *
Minimum fan speed
--
* See T bles on SECTION 12.4
NOTE : to displ y p r meters P71 nd P72 it is necess ry to set before the p r meter P22 = 22

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BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
ERROR CODE HISTORY
The B xi Lun Duo Tec PCB is ble to store the l st 10 errors th t h ve occurred. The PCB is
progr mmed with counter which counts consecutive errors of the s me error code.
In order to view the error code history scroll to COO fter P31 s described in the Accessing
P r meters
C00
Errors without
reset
1 – Error stor ge number (C00 is the l st error to occur)
2 – Error code
3 – Consecutive error code counter of the s me error
4 – Number of d ys p st since the error (00= tod y)
5 – System st tus
6 – System ph se
7 – Centr l he ting temper ture t the time of the error in °C
C01
C02
C03
C04
C05
C06
C07 Errors with
reset
C08
C09
SYSTEM STATUS
01 St nd by
02 DHW request
03 Controller stop function
04 CH request
05 Prehe t function
06 CH frost protection function ctive
07 DHW frost protection function ctive
08 Post-circul tion pump ctive
09 Overhe ting circul tion pump function ctive
SYSTEM PHASE
00 St nd by
01 Pre-purge function ctive
03 Ignition lo d purge between the first nd second ttempt
04 Ignition lo d first ttempt
05 Oper tion ctive
06 Lock out
08 Second ignition lo d ttempt
11 Ignition lo d purge between the second nd third ttempt
14 Third ignition lo d ttempt
15 Post- purge function
16 Overhe t post-purge function ctive

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
Parameters
Error
storage
number
Error code
Consecutive
error code
counter of
the same
error
Number of
days pasted
since the
error
00= today)
System
status
System
phase
Central
heating
temperature
at the time
of the error
in °C
Errors with
out reset
P32 C00
P33 C01
P34 C02
P35 C03
P36 C04
P37 C05
P38 C06
Errors with
reset
P39 C07
P40 C08
P41 C09

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
Error
Code Error Solution
09 G s v lve connection f ult.
-
Check connection t the g s v lve nd PCB
-If both connections re good repl ce PCB
Notes:
10 Outdoor sensor f ult.
-
Disconnect the outdoor temper ture sensor nd T
ke n
ohm re ding
refer to
NTC sensor
ch
rt
-Check the wiring to the outdoor temper ture sensor looking for bre k or short in the wire
-If the outdoor temper ture sensor nd wiring re good repl ce the PCB
Notes:
15 G s v lve comm nd f ult. -Check the wiring h rness connection t the g s v lve nd PCB
-If wiring h rness is good, repl ce PCB
Notes:
20 Centr l He ting NTC sensor
f ult.
-
T ke n Ohm re ding of the CH NTC supply sensor
refer to ch rt. The sensor should re d within +
/
-
10% of the st ted ohms on the NTC sensor ch rt, if out of c libr tion repl ce sensor.
- If the sensor is good, check the wiring h rness for loose or broken wires
- If the sensor nd wiring re good repl ce the PCB
Notes:
28 Flue NTC he t exch nger
sensor f ult
-
Check wiring h rness connections t the flue h
igh
limit
nd control bo rd for loose connection
-Check wiring h rness for short
Note:

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
40 Return NTC sensor f ult.
-
T ke n Ohm re ding of the return
NTC sensor refer to ch rt. The sensor should re d within +
/
-
10% of the st ted ohms on the NTC sensor ch rt, if out of c libr tion repl ce sensor.
- If the sensor is good, check the wiring h rness for loose or broken wires
- If the sensor nd wiring re good repl ce the PCB
Note:
50 Domestic Hot W ter NTC
sensor f ult
-
T ke n Ohm re ding of the
DHW
N
TC supply sensor refer to
NTC sensor
ch rt. The sensor should
re d within +-10% of st ted ohms on the ch rt, if out of c libr tion repl ce sensor.
- If the sensor is good, check the wiring h rness for loose or broken wires
- If the sensor nd wiring re good repl ce the PCB
Note:
53 Obstruction in the flue pipe.
-
Check
for obstruction i
n the flue pipe
-Ensure the vent is sloped b ck tow rds the boiler 3/4” per 3.3’ nd m ke sure there re no dips in
the venting
-With the unit se led put your combustion n lyzer in the int ke test port. This should re d CO of
0ppm, if there is CO this would indic te pinched g sket on the inner pipe (exh ust pipe).With
concentric venting system
-Check the combustion settings using combustion n lyzer. Refer to section 12.3 Chimney sweep
function – Combustion djustment function in the inst ll tion m nu l.
Note:

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
55 PCB not progr mmed.
-
Ensure the memory stick is connected properly to the PCB
-Follow the instructions PCB Repl cement (with e sy key service) in the troubleshooting guide or
the instructions th t re provided with the new PCB
Note:
83-84-85-
86-87
Communic tion problem
between boiler bo rd nd
control unit.
-
Check the wiring connection between the B xi modul ting room unit nd the M2 bus term
in l
position 1 & 2
-Check for short circuit in the wiring.
Note:
109 Pre-circul tion l rm
(tempor ry f ult).
-
Check
pump to ensure it is running nd is not ce sed or sticking
-Check for restrictions in the boiler nd system
-Ensure wiring to pump is not disconnected
-Ensure ll ir is purged from the system
-Check th t the he ting supply nd return sensor re clipped to the proper pipes nd re not
h nging in the ir.
Note:

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
110 S fety thermost t tripped
due to over temper ture
-
Check pum
p to m ke sure the impeller is spinning nd not cre sed
-Check for restrictions
-Ensure that all air is out of the system
- Ensure wiring to pump is not disconnected
-Use multi meter nd ohm(Ω) test the high limit (0Ω switch closed, OL switch open)
-if E110 persists repl ce the high limit sensor
Note:
118 Hydr ulic pressure too low.
-
Check system pressure. If necess ry fill system
reference the
inst ll tion m nu l section 2.7
system volume in the m nu l
-ensure ll ir is purge from the system nd ll shutoff v lves re open
-Ensure the exp nsion t nk is pressurized s per the inst ll tion m nu l section 2.7 system volume
-if the system is pressurized over 7psi / 0.5b r, check the low w ter cutoff using multi meter set
to ohms. If it re ds OL nd system is pressurized then repl ce low w ter cutoff
Note:
125 No circul tion of the w ter
-
Check
pump to ensure it is running nd not ce sed
-Check for restrictions
-Ensure wiring to pump is not disconnected or bre k in the wire
-Ensure ll ir is purged from the system
-M ke sure he ting supply nd return sensor re securely tt ched to the he ting pipes
Note:

BAXI LUNA DUO -TEC TROUBLESHOOTING GUIDE
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Version 1
128 Loss of fl me.
-Check the fl me sensor g p to the burner
-Check the fl me sensor for ny d m ge or build up. If cle ning is required use n non- br sive
cloth
-Check fl me sensor wiring for loose connection or broken wire
- Check for proper pol rity nd grounding to the unit
-Check for dequ te g s pressure nd flow to the unit refer to the inst ll tion m nu l
-Check µA (micro- mps) re ding from fl me sensor.
-Check venting for flue recircul tion
Note:
130 NTC flue sensor tripped due
to over temper ture.
-
Check pump to ensure it is moving properly nd is not ce sed
- Inspect he t exch nger for ny block ges. If the he t exch nger is blocked flue g s m y not be
exh usted properly c use high temper ture situ tion.
-Check the vent to ensure there re no pinched g skets on the exh ust pipe. Ensure the venting is
sloped tow rds the unit nd the venting is properly support to prevent dips.
-Check for obstructions in the flue
-using combustion n lyzer verify the CO₂ v lues for high, low nd ignition fire re within the
p r meters given in the inst ll tion m nu l section 12.3 Chimney Sweep – Combustion Test
Note:

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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131 Thermo fuse tripped due to
over temper ture.
-Check the thermo fuse, use multi meter nd check for resist nce (OL indic tes the sensor
is broken nd 0 Ω indic tes its closed)
-Check the st tus of the prim ry exch nger. Repl ce the he t exch nger if necess ry.
Note:
133 Ignition f ilure
No Sp rk
- Check Power, pol rity nd grounding to the unit
-Check sp rk electrode nd wiring connection from the igniter to the PCB
-Ensure sp cing between electrode nd burner is m int ined. Refer to inst ll tion m nu l
No Fl me
-Ensure g s shut off is open nd the g s line is purged of ir
-Check wiring connections to the g s v lve & PCB – X36 nd X2 connector
-Check the resist nce of the coils:
Pin 1 nd 3 = 20 - 30 Ohm
Pin 2 nd 4 = 60 - 70 Ohm
If you do not receive n Ohm re ding repl ce the g s v lve. If you get Ohm re ding repl ce the
PCB
No Fl me Sign l
-Check the fl me sensor g p to the burner
-Check the fl me sensor for ny d m ge or build up. If cle ning is required use n non- br sive
cloth
-Check fl me sensor wiring for loose connection or broken wire

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
133 Ignition f ilure
-
Check for proper pol rity nd grounding to the unit
-Check for dequ te g s pressure nd flow to the unit refer to the inst ll tion m nu l
-Check µA (micro- mps) re ding from fl me sensor. Should be 3-5µA
Note:
134 G s supply v lve blocked.
-
Repl ce PCB
Note:
135 Intern l error.
-
Check pol rity, grounding nd ensure the unit is on dedic ted electric l circuit b
ck to the p nel
-Ensure no w ter or w ter residue is on the PCB. If there is sign of w ter d m ge repl ce PCB
- remove ll exterior controls to the unit nd unplug the unit. Let it sit for 20 minutes nd then plug
the unit b ck in nd reset it. If it does not reset repl ce PCB
Note:

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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160 F n f ult.
-
Ensure F n connections correct t f n nd PCB Connectors X11 & X23
-Is there 120V AC t f n termin ls connector X11 blue to brown. If not repl ce PCB
-ensure f n is not seized or sticking
Note:
162/
317
Incorrect power supply
frequency. -Ensure P 43 is set to 01
Note:
169 Flue pressure switch (cont ct
open)
-
Check venting for block ges
-ensure m ximum vent length is not exceeded for your venting system.
-Ensure venting is sloped correctly nd supported to prevent the vent from s gging
-Check inlet g s pressure. Ensure th t no more th n 1” w.c. pressure between st tic g s pressure
nd dyn mic g s pressure. If it is more th n this check pipe size nd g s regul tor
-Ensure proper oper tion of the pressure switch in the open nd closed positions
Note:

BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
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Version 1
164/
384 F ult fl me (p r sitic fl me).
-
Check for proper pol rity nd grounding to the unit
-Check venting for flue recircul tion
-Check wiring connections to the g s v lve & PCB – X36 nd X2 connector
-Check the resist nce of the coils:
Pin 1 nd 3 = 20 - 30 Ohm
Pin 2 nd 4 = 60 - 70 Ohm
If you do not receive n Ohm re ding repl ce the g s v lve. If you get Ohm re ding repl ce the
PCB
-Check for dirty fl me sensor. It should re d 3-5μA when fl me is present
-Check loc tion for high winds
Note:
165/
385 Input volt ge too low.
-
Check Power
t M1
-Ensure volt ge to the unit is not less th n 86 volts
-Ensure th t the power m int in const nt nd does not drop or spike
Note:

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Version 1
BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
MULTI ZONE RELAY CARD CONNECTION AND OPTIONS OPTIONAL ACCESSORY)
The multi zone rel y c rd c n be progr mmed for multiple outputs. The multi zone rel y c rd
connects to the PCB on the X34 connector. The multi zone rel y c rd h s two rel y which re
controlled by P04 (rel y 1) nd P05 (rel y 2) p r meters.
X2
Def ult p r meters re: P04 = 02 nd P05 = 04
01 Rel y is ctiv ted by c ll on the M1 Bus termin l position 1 & 2
02 Rel y is ctiv ted by c ll on the M2 bus termin l position 6 & 7
03 During Low w ter pressure switch f ult, the rel y is ctiv ted.
04 In the event of f ult the rel y is ctiv ted.
05 When the f n is oper ting the rel y is ctiv ted.
07 For ny CH or DHW request, the rel y is ctiv ted.
08 Rel y cont ct oper tes on n interv l timer depending on the F19 p r meter
( def ult = 7 minutes)
09 Rel y is ctiv ted if room unit is connected nd the DHW progr mming mode is
c lling
10 For e ch DHW c ll, the rel y is ctiv ted
13 For e ch Cooling c ll, the rel y is ctiv ted. (if the cool function is en bled).

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Version 1
BAXI LUNA DUO-TEC TROUBLESHOOTING GUIDE
PCB REPLACEMENT WITHOUT EASY SERVICE MEMORY STICK)
The procedure is s follows:
• Switch off the boiler nd m ke sure the unit is unplugged
• Remove the front p nel nd open the PCB pl stic box cover
• Remove the memory stick out of the pcb nd move it in the new one
•Pay attention when inserting the memory stick that it is put in the correct position on the
connector see the shape printed on the pcb and match the corners);
• Repl ce the pcb
• Close the pl stic box nd pl ce the front p nel to close the boiler
• plug the boiler in nd switch on the boiler
NO PARAMETER CHANGEs ARE NEEDED