Worcester ZSBR 7-28 ICS1 Installation and operation manual

Service Booklet for the Engineer
for Gas Condensing Boilers
6 720 610 333-00.1
R
ZSBR 7-28 ICS1 GC-Number: 41 108 04
ZWBR 8-30 ICC2 GC-Number: 41 108 09
ZBR 8-35 ICS1 GC-Number: 41 108 05
ZWBR 11-37 ICC1 GC-Number: 41 108 10
ZWBR 7-28 HE plus GC-Number: 47 311 56
ZWBR 11-35 HE plus GC-Number: 47 311 57
7 181 465 347 (01.07) OSW

7 181 465 347 (01.07)2
Contents
Contents
Safety precaut ons 3
Symbols 3
1 Layout of Appl ance (ZSBR/ZWBR) 4
2 Operat on 5
2.1 Standard d splay 5
2.2 D splay ng serv ce funct ons 5
2.3 Sett ng serv ce funct ons 5
2.4 Resett ng serv ce funct ons to factory sett ngs 5
2.4.1 Resett ng serv ce funct ons 0.0 to 4.9 to the r
factory sett ngs (Reset 1): 5
2.4.2 Resett ng serv ce funct ons 0.0 to 9.9 to the
factory sett ng (Reset 2): 5
3 Bo ler serv ce funct ons 6
3.1 Summary 6
3.2 Explanat on of serv ce funct ons 9
4 Rect fy ng faults 14
4.1 Bo ler fa lure codes nd cat on 14
4.1.1 ... on the bo ler 14
4.1.2 ... on the programmer (opt onal accessory) 14
4.2 Summary 14
4.2.1 Appl ance faults 14
4.2.2 Faults that are not nd cated on any d splay 14
4.3 How to use the fault tables 16
4.4 Faults nd cated on d splay 17
4.5 Faults that are not d splayed 36
4.5.1 Appl ance faults 36
4.5.2 Programmer faults 41
5 Append x 45
5.1 NTC values 45
5.1.1 Outs de temperature sensor 45
5.1.2 CH flow NTC sensor, heat store NTC
sensor, constant hot water NTC sensor
and hot water NTC sensor 45
5.2 Electron c schemes 46
5.3 L st of most mportant replacement parts 47
5.4 Approved corros on nh b tors and
ant -freeze flu ds for central heat ng water 48
5.5 Detect ng corros on by CFCs 49

7 181 465 347 (01.07)
Safety precaut ons
3
Safety precaut ons
Repa rs
BRepa rs may only be carr ed out by an approved
nstaller!
BBefore carry ng out any work on the appl ance,
sw tch t off at the master sw tch!
BEven when the appl ance s sw tched off at the mas-
ter sw tch, some components on the PCB control
board ns de the control box are st ll l ve.
Therefore:
BBefore carry ng out any work on the electr cal parts
of the appl ance fully d sconnect t from the power
supply (e. g. by means of fuse or c rcu t breaker)!
BFlue duct ng must not be mod f ed n any way.
BUse only or g nal spare parts!
Instruct ons to the customer
BAdv se the customer that he/she must not make any
mod f cat ons to the appl ance or carry out any
repa rs on t.
BDraw attent on to the need for an annual serv ce (or
ma ntenance contract f appl cable).
Symbols
S gnal words nd cate the ser ousness of the hazard n
terms of the consequences of not follow ng the safety
nstruct ons.
•Caut on nd cates that m nor damage to property
could result.
•Warn ng nd cates that m nor personal njury or ser -
ous damage to property could result.
•Danger nd cates that ser ous personal njury could
result. In part cularly ser ous cases, l ves could be at
r sk.
Notes conta n mportant nformat on n cases where
there s no r sk of personal njury or damage to property.
Safety nstruct ons n th s document
are dent f ed by a warn ng-tr angle sym-
bol and are pr nted on a grey back-
ground.
iNotes are dent f ed by the symbol shown
on the left. They are bordered by hor zon-
tal l nes above and below the text

7 181 465 347 (01.07)4
Layout of Appl ance (ZSBR/ZWBR)
1 Layout of Appliance ( SBR/ WBR)
Fan f x ng
screws
Burner f x ng
screws
Electrode
assembly:
Flame sens ng
electrode
Ign t on electro-
des
CH flow NTC
sensor
CH flow safety
temperature
l m ter
Var able-charac-
ter st c pump
Automat c vent
G
as flow
restr ctor: adju-
s
t ng screw for
C
O2 max.
Gas valve:
adjust ng
screw for CO2
m n.
Plate-type heat
exchanger
(ZWBR)
Hot water NTC
sensor (ZWBR)
CH flow
S lencer
Fan
Fan connector
M xer un t
Condensat on
trap
Gas supply
p pe
Flue gas safety
temperature
l m ter
Test ng po nts:
flue gas
a r
Inspect on
open ng
Water sw tch
(ZSBR)
Change-over
valve motor
Change-over
valve
Heatron c
Transformer

7 181 465 347 (01.07)
Operat on
5
2 Operation
Instruct ons on the use of the text d splay module are
g ven n the operat ng and nstallat on nstruct ons for
the bo ler.
Fig. 1 Controls
aD splay
b“Up” or “More” button
c“Down”, or “Less” button
d“Back” button
e“Nest” button
f“Delete” button
2.1 Standard display
The text d splay shows the t me, the CH flow tempera-
ture and the measured outs de temperature n pla n
Engl sh.
In add t on, the 2-d g t d splay also shows the current
CH flow temperature n Heat ng mode and Hot Water
mode (d splay range 00 °C to 99 °C).
2.2 Displaying service functions
BPress any button to act vate the ma n menu.
BPress or button unt l the arrow cursor s
po nt ng to Sett ngs.
BPress the button.
BPress or button unt l the arrow cursor s
po nt ng to Serv ce .
BPress the button.
BPress button to select D splay serv ce
parameters.
Serv ce funct on 0.0, Last fault s d splayed.
BPress or button to cycle through the
current sett ngs.
BPress button to ex t the menu.
2.3 Setting service functions
BPress any button to act vate the ma n menu.
BTaste or button unt l the arrow cursor s
po nt ng to Sett ngs.
BPress the button.
BPress or button unt l the arrow cursor s
po nt ng to Serv ce.
BPress the button.
The cursor s po nt ng to D splay serv ce
parameters.
BPress and hold the button (for about 5 sec-
onds) unt l the d splay shows shows Adjust serv ce
parameters and the f rst serv ce funct on to be set,
e.g. 2.0, Operat ng mode. If a fault has occurred, the
d splay w ll show 0.0 and the last fault.
BPress or button unt l the des red serv ce
funct on s d splayed.
BPress the button.
The f rst l ne of the d splay shows Change value.
BUse the and buttons to enter the
requ red sett ng.
BPress the button.
The text d splay shows ATTENTION Store set-
t ngs?.
BPress or to select yes or no.
BPress to conf rm your select on.
The text d splay shows Please wa t ..., and the serv-
ce funct on s then d splayed w th the new sett ng.
BPress the or button unt l the next func-
t on you w sh to change s d splayed.
-or-
BPress the button to ex t the menu.
2.4 Resetting service functions to fac-
tory settings
2.4.1 Resetting service functions 0.0 to 4.9 to
their factory settings (Reset 1):
BPower OFF the appl ance.
BPress the button and keep t pressed.
BSw tch on the appl ance, press and hold the but-
ton unt l the
d splay shows r1 followed by [ ] .
2.4.2 Resetting service functions 0.0 to 9.9 to
the factory setting (Reset 2):
BPower OFF the appl ance.
BS multaneously press and hold buttons and .
BSw tch on appl ance, press and hold the and
buttons unt l the d splay shows r2 followed by [ ] .
c
b
a
fed
C
6 720 610 337-08.1R
iTo reset all parameters (except serv ce
sett ngs) set on the text d splay module):
BPress and hold the button unt l the
sett ngs are deleted.
C

7 181 465 347 (01.07)6
Bo ler serv ce funct ons
3 Boiler service functions
3.1 Summary
Text display message Display
Range adjustable
from - to
Reset
Value
0.0 Last fault 00 - FF Clear only 0
0.1 Flow temp. sensor 0 - 99 °C - -
0.2 Hot water temp. sensor 0 - 99 °C - -
0.3 Stor. tank temp. sensor1 0 - 99 °C - -
0.4 Stor. tank temp. sensor2 0 - 99 °C - -
1.2 Code plug 8714411 XXX 0 - 255 - -
1.5 Requ red flow temp. 0 - 99 °C - -
1.9 Module detect on no module detected
bus module
--
2.0 Operat ng mode - normal
M n
Max
normal
2.2 Pump sw tch mode - 1 - 3 2
2.3 Stor. tank charge output - 0 - 100% 100 %
2.4 Ant -cycle mode - 0 - 15 m n 3 m n
2.5 Max. flow temperature - 35 - 88 °C 88 °C
2.6 Sw tch.d ff.flow temperature - 0 - 30 °C 0 °C
2.7 Autom. ant -cycle mode - on
off
on
2.9 Actual output 0 - 100 % - -
3.0 Fan speed 0 - 255 U/s - -
3.3 Ion sat ons current no
low
m ddle
h gh
--
3.4 Pump mode - 0 - 3 01)
3.5 Pump block ng t me - 0 - 240 s
n 15-s ncrements
0 s
3.6 Software vers on BF 11.XX - -
Table 1

7 181 465 347 (01.07)
Bo ler serv ce funct ons
7
3.9 L nk 8 - 9 open
closed
--
L nk Ls-Lr open
closed
--
4.0 Stor. tank. therm.. (7-9) blocked
heat demand
--
4.1 Room therm. LSM blocked
heat demand
--
LSM release blocked
heat demand
--
4.2 T mer ch. 1 (heat ng) blocked
heat demand
--
T mer ch. 2 (hot wat.) blocked
heat demand
--
4.4 Heat demand (heat ng). yes
no
--
Heat demand (stor. tank). yes
no
--
4.5 Heat demand (hot water). yes
no
--
Keep hot per od yes
no
--
4.6 Internal regulator blocked
heat demand
--
5.0 Max. output (heat ng) - 27 - 100% 100 %
5.1 Permanent gn t on - no
yes
no
5.2 GFA status / error 00h - FFh - -
5.5 M n. output - 27 - 100 % 27 %
5.8 Cycl c bo ler starts - on
off
on
5.9 Fan speed (start) - low
h gh
low
6.7 Pump off (hot water). - off
on
off
Text display message Display
Range adjustable
from - to
Reset
Value
Table 1

7 181 465 347 (01.07)8
Bo ler serv ce funct ons
6.8 Cycle t me (hot water) - 0 - 60 m n 0 m n
6.9 Durat on (hot water) - 0 - 30 m n 1 m n
7.0 Pump map (heat ng) - 0 Pump step adjustable
1 Const. pressure h gh
2 Const. pressure
m ddle
3 Const. pressure low
4 Prop.pressure h gh
5 Prop.pressure low
4 Prop.
pres-
sure
h gh
7.1 Map pump step (heat.). - 2 - 7 7
7.2 Ant block. map pump. - off
on
on
7.3 A r purge mode - off
on autom. deakt vat.
permanent on
on
autom.
deakt v
at./ off
7.4 Actual map pump step 1 - 8 - -
7.5 Map pump load ndex 0 ... 255 - -
7.6 Map pump type 0 .. 99 - -
7.7 Output reduct on - off
only n heat ng mode
only n hot water mode
n heat./hot water mode.
only n
heat ng
mode
8.5 S phonf llprogram - on, bo ler m n.output,
on, adjust. m n output,
off
on,
bo ler
m n.
output
9.2 Hot water on demand - off
on
on
9.3 GFA-As c-error 00h - FFh - -
1) The reset value depends on the code plug.
Text display message Display
Range adjustable
from - to
Reset
Value
Table 1

7 181 465 347 (01.07)
Bo ler serv ce funct ons
9
3.2 Explanation of service functions
0.0 Last fault
The last fault can also be recalled for serv c ng pur-
poses when the appl ance s funct on ng correctly.
To delete the stored fault:
BDelete fault (no fault d splayed).
BPress the button.
BUse the or button to select yes.
BPress the button.
If a l st of the last 10 nd cated faults s requ red for serv-
c ng purposes, look under Sett ngs -> Serv ce -> Fur-
ther opt ons -> Fault h story.
0.1 Flow NTC
The temperature measured by the NTC sensor on the
CH flow p pe s nd cated.
0.2 Hot water NTC
The temperature measured by the NTC sensor on the
plate-type heat exchanger outflow s nd cated.
0.3 Storage tank NTC 1
Ind rectly heated heat store (SO..., SK..., ST...):
The temperature measured by NTC sensor 1 n the heat
store s nd cated.
Strat f ed-charge tank (ST...S):
The temperature measured by NTC sensor 2 at the bot-
tom of the heat store s nd cated.
0.4 Storage tank NTC 2
Strat f ed-charge tank (ST...S):
The temperature measured by NTC sensor 2 at the top
of the heat store s nd cated.
1.2 Code plug
The 10-d g t part number of the code plug s nd cated.
The code plug determ nes the appl ance funct ons. If
the appl ance s converted from natural gas to LPG or
v ce versa (us ng convers on k t) the code plug also has
to be changed.
1.5 Desired flow temp.
The CH flow temperature demanded by the text d splay
module or a programmer connected to the bus module
s d splayed.
1.9 Module detection
The text d splay module shows the modules detected
by the appl ance.
2.0 Operating mode
There are 3 operat ng modes to choose from.
•Normal mode: the appl ance operates accord ng to
the commands rece ved from the programmer.
•M n mode: the appl ance runs constantly at m n mum
output.
The text d splay shows MIn mode. The 2-d g t d s-
play alternates between the CH flow temperature
and – – .
•Max mode: the appl ance runs constantly at max -
mum output.
The text d splay shows Max mode. The 2-d g t d s-
play alternates between the CH flow temperature
and – –.
2.3 Stor. tank charge outp
The heat store charg ng output can be set to any level
between the m n mum and max mum rated heat output
for hot water accord ng to the heat transfer capac ty of
the heat store.
BEnter the heat store charg ng output sett ng on the
comm ss on ng record enclosed w th the appl ance.
2.4 Anti-cycle mode
Th s funct on s only act ve f serv ce funct on 2.7 Auto-
mat c ant -cycle mode s d sabled.
The ant -cycle t me s factory set to 3 m nutes.
The shortest poss ble per od s 1 m nute (recom-
mended for s ngle-p pe and hot-a r heat ng systems).
The sett ng 0 means that the ant -cycle t me s d sabled.
BEnter the ant -cycle t me on the comm ss on ng
record enclosed w th the appl ance.
2.5 Max. flow temperature
The max mum CH flow temperature can be set to
between 35 °C and 88 °C (factory sett ng).
2.6 Switch diff. flow NTC
The sw tch ng d fference s the perm ss ble dev at on
from the spec f ed CH flow temperature. It can be set n
ncrements of 1 K. The adjustment range s from 0 to
30 K (factory sett ng: 0 K). The m n mum CH flow tem-
perature s 30 °C.
BD sable ant -cycle t me (sett ng 0).
BThe sw tch ng d fference sett ng should be entered
on the comm ss on ng record suppl ed w th the appl -
ance.
iIf an outs de-temperature controlled heat-
ng programmer s used, no sett ng s re-
qu red.
The ant -cycle t me s opt m sed by the
programmer.
iIf an outs de-temperature controlled heat-
ng programmer s used, no sett ng s re-
qu red on the appl ance.

7 181 465 347 (01.07)10
Bo ler serv ce funct ons
2.7 Autom. anti-cycle mode
If an outs de-temperature controlled programmer s con-
nected to the appl ance, the ant -cycle t me s adjusted
automat cally.
Automat c adjustment of the ant -cycle t me can be d s-
abled. Th s may be necessary n the case of unfavoura-
bly d mens oned heat ng systems.
If automat c adjustment of the ant -cycle t me s d sa-
bled, the length of the ant -cycle t me must be set under
serv ce funct on 2.4.
BIf automat c adjustment of the ant -cycle t me has
been d sabled, th s should be entered on the com-
m ss on ng record enclosed w th the appl ance.
2.9 Actual output
The actual output of the appl ance at the t me v ewed s
d splayed.
3.0 Fan speed
The current fan speed s d splayed.
3.3 Ionisation current
The burner flame s mon tored by measur ng the on sa-
t on current generated dur ng combust on. If no on sa-
t on current s detected, the gas valve shuts off. Th s
ensures that unburned gas does not escape.
3.4 Pump mode ( BR.. models only)
The poss ble sett ngs are:
•Pump mode 1: f a heat ng pump and a 3-way valve
for charg ng the heat store are connected.
The 3-way valve s de-energ sed when the heat store
c rcu t s open.
•Pump mode 2 (factory sett ng): f a c rculat on
pump and a heat store charg ng pump are con-
nected. In ECO mode, f the c rculat on pump and the
heat store charg ng pump call for heat s multane-
ously, the system alternates between 12 m nutes
heat ng and 12 m nutes hot water.
•Pump mode 3: f a c rculat on pump and a heat store
charg ng pump are connected. In ECO mode, f the
c rculat on pump and the heat store charg ng pump
call for heat at the same t me, both pumps run s mul-
taneously. The heat store charg ng temperature has
pr or ty (up to 85 °C). The hydraul c conf gurat on
must be matched to th s pump mode (use of a m xer
un t and hydraul c balanc ng).
BThe pump mode sett ng should be entered on the
comm ss on ng record enclosed w th the appl ance.
3.5 Pump blocking time
( BR.. models only)
If the system ncorporates a 3-way valve external to the
appl ance, the heat ng pump s d sabled wh le the 3-way
valve s be ng actuated. therefore, the block ng t me of
the heat ng pump should be ≥ the actuat on t me of the
3-way valve.
The block ng t me has an adjustment range of 0 to 16,
w th each ncrement equ valent to 15 seconds. The
adjustment range therefore equates to 0 to 240 sec-
onds.
Factory sett ng s 30 seconds.
BEnter the pump block ng t me on the comm ss on ng
record enclosed w th the appl ance.
3.6 Software version
The vers on number of the software s d splayed.
3.9 Jumper 8 - 9 /
3.9 Jumper Ls - Lr
When suppl ed, the appl ance has a jumper f tted
across term nals 8-9 (= Heat demand). If that connec-
t on s opened (e.g. by a l m ter for an underfloor heat ng
system), heat ng mode s d sabled.
When suppl ed, the appl ance has a jumper f tted
across term nals Ls-Lr (= Heat demand). If that connec-
t on s opened (e.g. by an external 2-po nt programmer),
heat ng mode s d sabled.
4.0 Stor. tank therm. (7 - 9)
When suppl ed, the appl ance has no jumper across ter-
m nals 7- 9 (= D sabled). If that connect on s closed
(e.g. by a heat store thermostat) heat store charg ng s
enabled.
4.1 Room therm. LSM/ 4.1 LSM release
When suppl ed, a jumper s f tted across term nals LZ -
L1 on the LSM (= Heat demand). If that connect on s
opened (e.g. by a connected room thermostat), heat ng
mode s d sabled.
LSM release shows the total number of all poss ble ena-
ble s gnals connected v a the LSM. As soon as a mod-
ule connected to t (e.g. mechan cal l m ter for
underfloor heat ng, l m t sw tch on flue flap, combust on
a r flap, etc.) shuts off, heat ng and hot water modes are
d sabled.
4.2 Timer ch. 1 (heating)/ 4.2 Timer ch. 2
(hot water)
Shows the status of channel 1 of the t mer ntegrated n
the text d splay module or the separate programmer.
If that channel’s status s “Heat demand”, heat ng mode
w ll be act vated accord ng to the programmer com-
mands.
iOnly appl es f serv ce funct on 3.4, Pump
mode, s set to Pump mode 1 (external 3-
way valve for heat store charg ng s con-
nected). Otherw se has no funct on.

7 181 465 347 (01.07)
Bo ler serv ce funct ons
11
Shows the status of channel 2 of the t mer ntegrated n
the text d splay module or the separate programmer.
If that channel’s status s “Heat demand”, hot water
mode w ll be act vated accord ng to the programmer
commands.
4.4 Heat demand (heating)/
Heat demand (stor. tank) ( SBR.. only)
Heat demand (heat ng) shows the heat demand status
for the central heat ng system.
If th s channel’s status s “Heat demand”, heat ng mode
w ll be act vated accord ng to the programmer com-
mands.
Heat demand (stor. tank) shows the heat demand sta-
tus for charg ng the heat store.
If th s channel’s status s “Heat demand”, the heat store
w ll be charged accord ng to the commands from the
heat store thermostat or NTC sensor.
4.5 Heat demand (hot water)/
Keep hot period ( WBR... models only)
Heat demand (hot water) shows the heat demand sta-
tus for the hot water funct on.
If th s channel’s status s “Heat demand”, the hot water
funct on operates accord ng to the commands from the
hot water NTC sensor.
Keep hot per od shows the constant hot water c rcu t
status of the heat exchanger (ECO or Comfort mode).
If th s channel’s status s “Heat demand”, Comfort mode
s act ve. If the status s “D sabled”, ECO mode w th
demand detect on s act ve.
4.6 Internal regulator
The bo ler has an nternal ant -cycle funct on wh ch pre-
vents the burner overheat ng f the heat output can not
be d ss pated even n M n mode. The appl ance w ll then
sw tch off even when the system s call ng for heat.
It w ll subsequently sw tch on aga n
• after 5 seconds n hot water mode
• after 30 seconds n heat store charg ng mode
• after 0 to 15 m nutes n heat ng mode (depend ng on
the sett ng for serv ce funct on 2.4 Ant -cycle mode).
The ant -cycle funct on s cancelled by
• sw tch ng the appl ance off and on aga n at the mas-
ter sw tch,
• another demand for heat,
• act vat ng M n or Max mode
• or br efly sw tch ng to summer mode on the tempera-
ture control for CH flow.
5.0 Max. output (heating)
Some gas suppl ers demand an output-dependent
bas c charge.
The heat ng output can be l m ted to any level between
the m n. rated heat output and the max. rated heat out-
put to su t the spec f c heat requ rements.
The factory sett ng s max mum rated output – d splay
shows “100 %”.
5.1 Permanent ignition
Th s funct on allows permanent gn t on w thout gas
supply to be act vated for the purposes of check ng the
gn t on mechan sm.
5.2 GFA status/error
The status of the automat c gn t on module ntegrated
n the PCB control board s nd cated.
5.5 Min. output
The m n. heat nput s factory set, see techn cal data.
The modulat on range can be extended at the top end
to su t the ch mney cond t ons.
BRefer to sett ngs table for heat ng and heat store
charg ng output for deta ls of the m n. heat output n
kW and the correspond ng percentage (see nstalla-
t on nstruct ons for bo ler).
BEnter percentage on text d splay module and conf rm.
BMeasure gas flow rate and compare w th the f gures
quoted for the percentage shown. If d fferent, correct
the percentage f gure!
BEnter m n. rated heat output on the comm ss on ng
record enclosed w th the appl ance.
5.8 Cyclic boiler starts ( SBR 3/5-16 A... only)
When suppl ed, th s funct on s act vated on the above
appl ances and prevents start-up problems caused by
poor gn t on character st cs.
A truncated start cycle s act vated f the burner has not
been n operat on for more than 3 hours.
Dur ng a truncated start cycle, the fan runs and the gas
valve s opened long enough to completely f ll the gas
p pe w th gas (approx. 1 - 2 seconds) but the burner s
not gn ted.
Th s funct on s not requ red, and can not be act vated,
on any other models.
6.7 Pump off (hot water)
The appl ance s suppl ed w th th s funct on act vated,
.e. there s a delay before the pump sw tches on n hot
water mode. Th s means that cold water comes out of
the p pe to beg n w th, followed by hot water once the
pump sw tches on.
If the pump s set to sw tch on mmed ately (Pump off
funct on deact vated), the hot water temperature r ses
gradually unt l the set temperature s reached.
iEven f the heat ng output s l m ted, the full
rated heat output rema ns ava lable for hot
water or heat store charg ng.

7 181 465 347 (01.07)12
Bo ler serv ce funct ons
If a strat f ed-charge tank s connected, t s useful to
have the funct on act vated.
The delayed cut- n of the pump then prevents cold
water be ng pumped through the tank and cool ng t
down.
6.8 Cycle time (hot water) ( WBR... only)
The appl ance s suppl ed w th the hot water cycle t me
set to 3 m nutes.
The hot water cycle t me spec f es how long after hot
water s drawn the pump cont nues to pump water
through the nternal hot water system.
6.9 Duration (hot water) ( WBR... only)
The appl ance s suppl ed w th the hot water durat on
set to 3 m nutes.
The hot water durat on spec f es how long after hot
water s drawn heat ng mode rema ns d sabled.
7.0 Pump map (heating) (not BR...)
The appl ance s suppl ed w th th s funct on set to
“4 Prop. pressure h gh”(see pump character st c n
bo ler nstallat on nstruct ons).
The pump map nd cates how the pump s controlled n
heat ng mode. The pump sw tches between the var ous
pump speeds so as to reproduce the character st c
curve selected. (The current sett ng can be v ewed by
means of serv ce funct on 7.4.)
Chang ng the pump character st c can be helpful f a
lower pressure d fference w ll guarantee the necessary
c rculat on on the bas s of the system d mens ons and
pump character st c (see nstallat on nstruct ons).
If th s parameter s set to “0 Pump step adjustable”, then
the pump speed set under funct on 7.1 s act ve.
7.1 Map pump step (heat.) (not BR...)
The appl ance s suppl ed w th th s funct on set to 1 (see
pump character st c n bo ler nstallat on nstruct ons).
However, the sett ng s only act ve f funct on 7.0, Pump
map (heat ng), s set to “0 Pump step adjustable”.
Th s serv ce funct on corresponds to the pump speed
sw tch used on convent onal heat ng pumps.
7.2 Antiblock. map pump (not BR...)
The appl ance s suppl ed w th th s funct on act vated.
If the pump threatens to jam, an osc llat ng pump act on
s act vated. Afterwards, the requ red operat ng mode s
cont nued.
7.3 Aeration mode (not BR...)
The f rst t me the appl ance s sw tched on, a once-only
vent ng funct on s act vated. The heat ng pump then
sw tches on and off at ntervals. Th s sequence lasts
about 8 m nutes and the text d splay shows “Aerat on
mode”. The 2-d g t d splay shows “oo” n alternat on w th
the CH flow temperature. The automat c vent must be
opened and then closed aga n once the vent ng
sequence s complete.
• If the vent ng funct on s set to “On, autom. deact -
vat.”, once the sequence has been completed.
7.4 Actual map pump step (not BR...)
The currently act ve pump speed s d splayed (see func-
t on 7.0).
7.5 Map pump load index (not BR...)
The load ndex s d splayed.
7.6 Map pump type (not BR...)
The pump type code of the pump f tted s d splayed.
7.7 Output reduction
The appl ance s suppl ed w th th s funct on act vated. It
prevents overload of the heat exchanger w th h gh CH
flow temperatures.
The output of the burner s reduced accord ng to the
CH flow temperature, .e. up to 80 °C flow temperature,
full burner output s perm tted. Above 80 °C, the burner
output s reduced as flow temperature ncreases up to
90 °C at wh ch only m n mum output s ava lable (even
w th max mum heat demand).
Th s funct on can be deact vated for hot water and/or
central heat ng mode.
iIn order to save as much energy as poss -
ble and to m n m se the poss b l ty of water
c rculat on no se, a low character st c
should be chosen.
iThe vent ng funct on can be act vated
manually after serv c ng.

7 181 465 347 (01.07)
Bo ler serv ce funct ons
13
8.5 Siphon fill program
The trap f ll ng programme ensures that the condensa-
t on trap s f lled when the appl ance s f rst nstalled or
after t has been shut down for a long per od: The con-
densat on trap prevents flue gas escap ng from the
appl ance nto the room n wh ch t s nstalled.
The trap f ll ng programme s act vated:
• the appl ance s sw tched on at the master sw tch
• the burner has not been n operat on for at least 48
hours
• the appl ance s sw tched from summer to w nter
mode.
The next t me the heat ng or hot water system calls for
heat, the appl ance s held at m n mum output for 15
m nutes. The trap f ll ng programme rema ns act ve unt l
the appl ance has completed 15 m nutes of operat on at
m n mum output.
The text d splay shows “S phon f ll program” and the
2-d g t d splay alternates between „-II-“ and the CH flow
temperature.
The factory sett ng s „1“ (act vated).
9.2 Hot water on demand
The appl ance s suppl ed w th th s funct on act vated.
Th s funct on relates to mode, the button l ghts up.
The demand detect on funct on enables max mum gas
and water economy.
Br efly turn ng a hot water tap on and then off aga n s g-
nals demand to the appl ance wh ch then heats up the
water to the set temperature.
Hot water s then ava lable at short not ce.
9.3 GFA-Asic error (automatic ignition module,
extended messages)
The status of, or an error message from the automat c
gn t on module ntegrated n the PCB control board s
d splayed.
Warn ng: f the condensat on trap s not
f lled, flue gas can escape!
BOnly deact vate the trap f ll ng program-
me n order to carry out serv c ng work.
BAlways re-act vate trap f ll ng program-
me once serv c ng s complete.

7 181 465 347 (01.07)14
Rect fy ng faults
4 Rectifying faults
4.1 Boiler failure codes indication
4.1.1 ... on the boiler
In order to dent fy the spec f c bo ler fa lure a two d g t
alphanumer c code s used. Th s allows a qu ck fault
dent f cat on and solut on.
The text d splay shows the message Fault EA. Please
call serv ce, for example. At the same t me, the fault
code appears on the 2-d g t d splay, n th s example: EA.
You can v ew an explanatory descr pt on of the fault nd -
cated by go ng to Sett ngs -> Serv ce -> Serv ce
parameters, n th s example: EA: Dur ng operat on:
Flame not detected.
The fa lures can be d v ded nto four bas c typolog es, as
descr bed:
• The appl ance cont nues to work at a m n mum func-
t on level (e. g. w th error codes A5, A7, A8, AC, Ad,
CC, FC).
• The appl ance s locked unt l the fa lure s repa red
(e. g. w th error codes (b1, C1, d1, d3, E2, F0)).
• The appl ance s locked, unt l the ON/OFF sw tch s
turned (A1).
• The bo ler has shut down and locked out ( flashes)
and rema ns so unt l the cause of the fault has been
el m nated and the lock-out cancelled (e.g. E9, EA,
F0, F7, FA,Fd).
4.1.2 ... on the programmer (optional accessory)
A TW 2 remote control un t can also be connected to
the text d splay module.
If other/more funct ons are requ red, another program-
mer must be connected. Those programmers are then
controlled v a the bus module BM1.
For more deta led nformat on, refer to the nstallat on
nstruct ons for the bo ler and the nstalled programmer.
Faults on th s programmer are nd cated by text mes-
sages on the programmer d splay.
Once the fault has been put r ght, the programmer
reverts to ts normal d splay.
4.2 Summary
4.2.1 Appliance faults
4.2.2 Faults that are not indicated on any dis-
play
iTo unblock the appl ance:
BPress the unblock button unt l the
d g t –– appears on the d splay.
Once the appl ance starts up success-
fully, the fault d sappears from the text
d splay.
Appl ance faults
ZBR ... A ZSBR ... A ZWBR ...A Page
A1 X X 17
A5 X 18
A7 XXX 19
A8 XXX 20
Ad XXX 21
b1 XXX 22
C1 XXX 23
d3 XXX 24
E2 XXX 25
E9 XXX 26
EA XXX 28
F0 XXX 32
F7 XXX 33
FA XXX 34
FC XXX 35
Fd XXX 35
Table 2
Appl ance faults
ZBR ... A ZSBR ... A ZWBR ...A Page
Excess ve burner no se, rum-
bl ng no ses
XXX 36
Flue gas levels ncorrect, CO
level too h gh
XXX 37
Ign t on too harsh, gn t on
poor
XXX 38
Bo ler nd cates P1, P2, P3 at
start-up and then restarts
w th P1, ...
XXX 36
Table 3

7 181 465 347 (01.07)
Rect fy ng faults
15
Loose or broken contact on
heat store NTC sensor
XX 39
Spec f ed CH flow tempera-
ture from TA... programmer
exceeded
XX 40
Programmer faults
TR 2 Page
Set room temperature not
reached
X41
Set room temperature
exceeded by large amount
X43
Set room temperature not
reached
41
Temperature r ses nstead of
fall ng
X43
Room temperature too h gh n
Economy mode
X43
Incorrect or no modulat on X 43
Heat store fa ls to heat up 44
Table 4
Appl ance faults
ZBR ... A ZSBR ... A ZWBR ...A Page
Table 3

7 181 465 347 (01.07)16
Rect fy ng faults
4.3 How to use the fault tables
The procedure is explained using the fault code
EA as an example:
The table head ng shows the fault code and a general
descr pt on of the fault.
In the example shown, you are nstructed to note the
current sett ngs before go ng any further. If you can see
the flame (answer to quest on s “yes”) you move on to
Step 5. (↓ 5.). The quest on asked n Step 5 s “Is there
a problem w th the flue”. The flue must then be checked.
If the answer to the f rst quest on (“Is burner flame v s -
ble?”) was“no””, then you go to and answer Quest on 2,
“Is the gas cock turned on?”. If the gas cock s turned
off, t must be turned on and the appl ance reset. To do
so, you press the button. Restart the appl ance and
run through a complete heat-demand cycle unt l the
appl ance sw tches off.
If the fault s now cured, the appl ance w ll revert to nor-
mal operat on and the fault-f nd ng process s complete.
Now s mply re-check the sett ng of the two temperature
controls.
If the fault EA recurs dur ng the heat-demand cycle, t
w ll be shown on the d splay aga n. In that case cont nue
the fault f nd ng procedure from Step 3 (thermal cut-out
n gas cock) as descr bed above.
If a d fferent fault code s d splayed after the heat-
demand cycle, f nd the appropr ate sect on of the fault
f nd ng table and work through the procedure descr bed
step by step.
EA and flashing.
Flame not detected
Check Action
1. Is burner flame v s ble? yes: ↓5.
no: ↓2.
2. Is the gas cock turned on? yes: ↓3.
no: BTurn on the gas cock.
BPress , does appl ance restart???
EA? ↓3.
3. D d the thermal secur ty of the gas
cock lock out?
yes: B...
no: ↓ ...
4. ...
5. Is there a problem w th the flue?
BCheck CO2 level n combust on
a r.
> 0,2 % CO2?
yes: BCheck the flue.
no: ↓ ....
... ...

7 181 465 347 (01.07)
Rect fy ng faults
17
4.4 Faults indicated on display
A1 flashing.
Controlled-characteristic pump has run dry
Check Action
1. System pressure below 1.2 bar? yes: BPower OFF the appl ance.
BCheck appl ance and system for water leaks and
repa r as necessary.
BTop up system.
BTurn ON the appl ance.
A1? ↓2.
no: ↓2.
2. Act vate vent ng sequence. BAct vate menu opt on Show serv ce parameters.
BSelect 7.3 Aerat on mode select sett ng On,
autom. deact vat. and conf rm.
BVent appl ance1).
BVent rad ators.
↓3.
1) See nstallat on nstruct ons
3. Aud ble bear ng damage on pump? yes: BPower OFF the appl ance.
BDra n appl ance.
BReplace pump.
BTop up system.
BTurn ON the appl ance.

7 181 465 347 (01.07)18
Rect fy ng faults
A5 flashing.
Heat store NTC sensor 2 defective
Check Action
1. BAct vate menu opt on
Show serv ce parameters.
BSelect
.4 Stor.tank temp.sensor2 .
Is a temperature between 0. and 5.
d splayed?
yes: BIs the connector for heat store NTC sensor 2 cor-
roded1), damaged or d rty? Replace affected
components.
↓2.
1) For notes, refer to Append x.
no: ↓3.
2. BD sconnect connector for heat
store NTC sensor 2.
BShort-c rcu t the 2-p n connector
on the end of the 20-p n connector
lead assembly.
After max. 60 sec:
D splay changes to temperature
between 100. and 95.?
yes: BPower OFF the appl ance.
BChange heat store NTC sensor 2.
BPlug the connect on w re.
BTurn ON the appl ance.
A7? ↓3.
no: BChange the 20-p n connector lead assembly.
↓3.
3. Temperature between 95. and 100. s
d splayed.
BUnplug the connector.
After max. 60 sec.:
Does the d splayed code change
to a value between 0. and 5.?
yes: BPower OFF the appl ance.
BChange heat store NTC sensor 2.
BPlug the connect on w re.
BTurn ON the appl ance.
A7? ↓4.
no: ↓4.
4. BUnplug the 20-p n connector lead
assembly from the Heatron c.
After max. 60 sec.:
Does the d splayed code change
to a value between 0. and 5.?
yes: BChange the 20-p n connector lead assembly.
no: BPower OFF the appl ance.
BD sconnect the bo ler electr cal connect on.
BChange PCB control board.
BReconnect the bo ler electr cal connect on.
BTurn ON the appl ance.

7 181 465 347 (01.07)
Rect fy ng faults
19
A7 flashing.
Hot water NTC sensor defective
Check Action
1. BAct vate menu opt on
Show serv ce parameters.
BSelect
.2 Hot water temp.sensor .
Is a temperature between 0. and 5.
d splayed?
yes: BIs the connector for hot water NTC sensor corro-
ded1), damaged or d rty? Replace affected com-
ponents.
↓2.
1) For notes, refer to Append x.
no: ↓3.
2. BD sconnect connector for hot
water NTC sensor.
BShort-c rcu t the 2-p n connector
on the end of the 20-p n connector
lead assembly.
D splay changes to temperature
between 100. and 95.?
yes: BPower OFF the appl ance.
BChange hot water NTC sensor.
BPlug the connect on w re.
BTurn ON the appl ance.
A7? ↓3.
no: BChange the 20-p n connector lead assembly.
↓3.
3. Temperature between 95. and 100. s
d splayed.
BUnplug the connector.
After max. 60 sec.:
Does the d splayed code change
to a value between 0. and 5.?
yes: BPower OFF the appl ance.
BChange hot water NTC sensor.
BPlug the connect on w re.
BTurn ON the appl ance.
A7? ↓4.
no: ↓4.
4. BUnplug the 20-p n connector lead
assembly from the Heatron c.
After max. 60 sec.:
Does the d splayed code change
to a value between 0. and 5.?
yes: BChange the 20-p n connector lead assembly.
no: BPower OFF the appl ance.
BD sconnect the bo ler electr cal connect on.
BChange PCB control board.
BReconnect the bo ler electr cal connect on.
BTurn ON the appl ance.

7 181 465 347 (01.07)20
Rect fy ng faults
A8 flashing.
No correct electrical connection
Check Action
1. Mode selector sw tch s between two
sett ngs
BTurn sw tch unt l t cl cks nto pos t on.
A8? ↓2.
2. BPower OFF the appl ance.
W r ng between TR 2 and text-
d splay OK?
• Term nal 3 on TR 2 connected to
Term nal 3 on textd splay ?
• Term nal 4 ... Term nal 4 ....
etc.
yes: BTurn ON the appl ance.
↓3.
no: BRew re correctly as spec f ed n the nstallat on
nstruct ons.
BTurn ON the appl ance.
after 90 sek.:
A8? ↓3.
3. Lead(s) defect ve. BCheck leads for cont nu ty and replace as
necessary.
A8? ↓4.
4. TR 2 defect ve. BPower OFF the appl ance.
BChange TR 2 .
BTurn ON the appl ance.