Rotex A1 BG Inline User manual

For the operator
ROTEX A1 BG Inline
Gas condensing boiler
Operating manual
Type Rated thermal output
ROTEX A1 BG 25i 5 - 25 kW modulating
ROTEX A1 BG 40i 8 - 40 kW modulating
ROTEX A1 BG 25i F 5 - 25 kW modulating
ROTEX A1 BG 40i F 8 - 40 kW modulating
Manufacture number
Customer service
0085 AS 0011  GB
Edition 10/2007

Guarantee and conformity
2BA ROTEX A1 BG Inline - 10/2007
ROTEXaccepts the guaranteeformaterial and manufacturingdefects accordingtothisstatement. Within theguarantee period,
ROTEX agrees to have the device repaired by a person assigned by the company, free of charge.
ROTEX reserves the right to replace the device.
The guarantee is only valid if the device has been used properly and it can be proved that it was installed properly by an expert
firm.Asproof,westronglyrecommendcompletingtheenclosedinstallationandinstructionforms andreturningthem to ROTEX.
Guarantee period
The guarantee period begins on the day of installation (billing date of the installation company), however at the latest 6 months
after the date of manufacture (billing date). The guarantee period is not extended if thedevice is returned for repairs or if the
device is replaced.
Guarantee periodfor the burner and boiler electronics: 2 years
Guarantee periodfor the boiler body: 10 years.
Guarantee exclusion
Improper use, intervention in the device and unprofessional modifications immediately invalidate the guarantee claim.
Dispatch and transport damage are excluded from the guarantee offer.
The guarantee explicitly excludes follow-up costs, especially the assembly and disassembly costs of the device.
There is no guarantee claim for wearing parts (according tothe manufacturer's definition), such aslights, switches, fuses.
Declaration of conformity
For condensing heating centres from the ROTEX A1 BG xxi boiler series.
We, ROTEX GmbH, declareunder our sole responsibility that theproducts
Product Order No.
ROTEX A1 BG 25i 15 58 00
ROTEX A1 BG 40i 15 58 01
ROTEX A1 BG 25i F 15 58 10
ROTEX A1 BG 40i F 15 58 20
with the product identificationnumber CE 0085 AS 0011,
comply, in their standard design, with the following European Directives:
2004/108/CE Electromagnetic compatibility
directive
90/396/CEE Gas appliances directive
2006/95/CE Low voltage directive
92/42/CEE Boiler efficiency requirements
directive
Güglingen, 1.11.2006 Dr Eng. Franz Grammling
Managing Director

Table of Contents
3
ROTEX A1 BG Inline - 10/2007
1 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1 See the manual . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 4
1.2 Warnings and symbols. . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . 4
1.3 Danger prevention. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 5
1.4 Proper use. . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 5
1.5 Instructions for operating safety. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . 5
2 Product description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1 Boiler structure and components. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . 7
2.2 Brief description . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . 8
2.3 Gas burner - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - - 9
2.4 Connection . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . 10
2.5 Hot water storagetank (not included in scopeof supply). . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . 11
3 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.1 Safety. . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. 13
3.2 Instructions for erection . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . 13
3.3 Initial start-up. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 14
3.4 Instructions and handover to the operator. . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . 14
4 Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.1 Operating elements on the boiler control panel. . . . . . . . . .. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . 15
4.1.1 Overview and brief description . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . 15
4.1.2 Display and modification of the parameters. . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . 17
4.2 Heating mode . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . 18
4.2.1 Manual setting of the boiler temperature. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . 18
4.2.2 Pumping settingfor an energy-setting operation . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.2.3 Tips about operating noises . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 19
4.3 Temporary shutdown . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 19
4.4 Recommissioning. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 20
4.4.1 Work for recommissioning. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . 20
4.4.2 Checklist for recommissioning. . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 21
5 Inspection and maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.1 Generalities about inspection undmaintenance . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . 22
5.2 Inspection and maintenance tasks. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 22
5.2.1 Removing panelling (and cleaning it) . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.2.2 Checking the connections and conduits. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . 23
5.2.3 Checking and cleaning the condensatedrain.. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . 23
5.2.4 Checking and cleaning the burner . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .. . . . 24
6 Faults and Failures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
6.1 Fault detection andtroubleshooting. . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . 26
6.2 Emergency operation. . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . 26
6.3 Failures- - - - - - - - -- - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - 27
6.4 Fault code. . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 27
7 Technical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8 Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
9 For the chimney sweep. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

1 xSafety
4BA ROTEX A1 BG Inline - 10/2007
1Safety
1.1 See the manual
This manual is addressed to the operator of the gas condensation boiler A1 BG xxi.
The erection, connection and the initialstart-up of the gas condensation boiler are executed by authorised and trained heating
experts.Thegascondensationboilerwashandedovertoyoubytheinstaller.Thehandoverhasbeendocumentedinthehandover
report.
All the necessaryactivities for operation,recommissioning after a temporary shutdown as well some basic maintenance work
are described inthis manual. Activities for initial start-up, troubleshooting and maintenance, which are not described in this
operation manual, may be carried out only by authorised and trained heating experts.
Please read carefully through this manual before operating the gas condensation boiler.
Relevant documents
Thedocumentslistedbelowarepartofthetechnicaldocumentationofthegas condensingboilerand mustthereforebeobserved.
The documents are included in the scope of supply.
– ROTEX A1 BG Inline: Installation and maintenance instructions for the heating expert,
– ROTEX Control THETA: Operating instructions for the heating engineer.
1.2 Warnings and symbols
Meaning of the warnings
The warnings are classified in this manual according to their severity and probability of occurrence.
Handling instructions
• Handling instructions are shown as a list. Actions during which the sequential order must be maintained are numbered.
ÎResults of actions are identified with an arrow.
Order number
You can recognise references to order numbers from the goods symbol .
DANGER!
Indicates a direct threat of danger.
Disregarding this warning leads to serious physical injury or death.
WARNING!
Indicates a potentially dangerous situation.
Disregarding this warning leads to serious physical injury or death.
CAUTION!
Indicates a possibly damaging situation.
Disregarding this warning can causedamage to property and the environment.
This symbol identifiesuser tips and particularly useful information, but not warningsor hazards.
Some types of dangers are
represented by special symbols: Danger of explosion, Electrical current, Danger of burning or scalding.

1 xSafety
5
BA ROTEX A1 BG Inline - 10/2007
1.3 Danger prevention
ROTEX gas condensing boilers are built according to the state-of-the-art andmeet all recognised technical requirements.
However,improperusecancauseseriousphysicalinjuriesordeath,aswellaspropertydamage.Toavoiddanger,onlyinstalland
operate ROTEX gas condensing boilers:
– As stipulated and in perfect conditions,
– With an awareness of safety and dangers.
Thisassumesknowledgeandapplicationofthecontentsofthis manualand instructionin theoperationofthegascondensation
boiler imparted by the installer.
Danger of explosion if you can smell gas
Escapinggas is adirectthreat to human lifeandhealth.Even minor sparkscantrigger major explosions.If you smell gas,please
follow these rules:
• Do not stoke open fire and do not operate an electrical switch.
• Open windows and ventilate the room well.
• Inform the authorised gas supply company.
1.4 Proper use
Thegas condensingboilerROTEXA1 BG xxicanonly beusedfortheheatingofhotwater heatingsystems.Thegas condensing
boiler must be installed, connected and operated as indicated in this manual.
Any other use outside the above considered as improper. The operator is solely responsiblefor the damages caused by this.
Properusealsoincludestheobservanceofmaintenanceandinspectionconditions.Sparepartsmustatleastsatisfythetechnical
requirements defined by the manufacturer. This is the case, for example, with original spare parts.
1.5 Instructions for operating safety
Heating system
• Have the work on the heating system (e.g. erection, connection and the initialstart up) done only by authorised and trained
heating experts.
• Switch off the mains switchwhen undertaking any work on the heating system and secure it againstbeing unintentionally
restarted.
• Erect the heating system as open or closed heating system according to the safety engineering requirements given in
EN 12828.
• The safety valves must conform to DIN EN ISO 4126-1 and components must be checked. The safety valves must be installed
in the safety inflow.
• The stickers on the gas condensingboiler must not be removed or damaged.
Electrical installation
• Allcontrolandsafetydevicesofthegascondensingboilerareconnectedreadytooperateandchecked.Modificationsonthe
electrical installation are dangerousand prohibited. The operatorwill be solely responsible for any damage thismay cause.
• Onlyqualifiedelectricalengineersshouldbeallowedtocarryoutworkontheelectricalsystem,observingthevalidelectrical
engineering guidelines as well as the specifications of the competent electricity supply company.

1 xSafety
6BA ROTEX A1 BG Inline - 10/2007
Gas installation
• Have the work on the heating and gas supply system carried out only by authorised and trained technical personnel.
• Have work on the gas burner carried out only by authorised and trained technical personnel.
Air/flue gas system (LAS)
• The operator may not modify the air/ flue gas system (LAS) under his authority. Modifications to the combustion air supply
andthefluegasconductionmaybemadeonlybyauthorisedandtrainedtechnicalpersonnelafter approvalfromtheDistrict
Master Chimney Sweep.
Unit installation room
• Only operate the gas condensing boiler if sufficient combustibleair supply is guaranteed. If operating the gas condensing
boilerindependentlyoftheambientairwithanair/fluegassystem(LAS)withdimensionsaccordingtoROTEX-Standard,this
is automatically guaranteed and there will be no further conditions required of the device installation room.
• Note that there must bean outside air opening of at least 150 cm2for ambient air-dependent operation.
• Donotoperatethegascondensingboilerasambientair-dependentinroomswithaggressivevapours(e.g.hairspray,perchlo-
roethylene, carbontetrachloride), strong dust formation (e.g. workshop) or high atmospheric humidity (e.g. laundry).
• Strictly keep the minimum distances to walls and other objects(see chapter 7).
Instructions by the installer
• The handover also comprises instructions for operation and inspection of the gas condensation boiler, based on the current
operating manual.
• Document the handover, by filling-in and signing the attachedinstallation and instruction form together with the installer.
Disposal
• Through the environmentally-friendly design of the gas condensing boiler, ROTEX has compliedwith the standards for
environmentally-friendly disposal.
• Properdisposalincompliancewiththerespectivenationalstipulationsofthecountryofuseistheresponsibilityoftheowner.
Documentation
• The technical documentation included inthe scope of supply is part of the device. It must be placed such that the operator
or the technical staff can also refer to it.

2 xProduct description
7
BA ROTEX A1 BG Inline - 10/2007
2 Product description
2.1 Boiler structure and components
A1 BG 25i A1 BG 40i A1 Schematic drawing
Fig. 2-1 Boiler components - View from the front Fig. 2-2 Diagram A1-boiler
A1 BG 25i A1 BG 40i
Fig. 2-3 Boiler components - View from the back
1 Silencer hood
2Boiler control panel
3Boiler panelling
4 Burner
5Control
6Boiler main body with heat and sound
insulation
7Nameplate with manufacture number
8Circulation pump
93-way switch valve
10 Heater return flow (cold)
11 Heater inflow (hot)
12 Pressure gauge
13 Filling and draining cock
14 Safety valve
15 Flue gas-/supply air connection
16 Condensate drain line
17 Condensation discharge
18 Supply air hoses
19 Flame tube
20 Combustion chamber insert
21 Flue gas temperature sensor
22 Circuit board (electrical connections)
23 Sticker for identification of the gas type to be
used
24 Documents pocket
25 Ball stopcock
26 Inflow temperature sensor
27 Return flow temperature sensor
28 Setting sticker
Safety devices

2 xProduct description
8BA ROTEX A1 BG Inline - 10/2007
2.2 Brief description
The ROTEX gas condensing boiler from the series A1 BG xxi is a completely pre-assembled gas condensing unit.
Operating instructions
TheROTEX gascondensingboilerA1BGxxi is designedin such awaythat it can be operatedindependentlyof ambient air. The
burner sucks the combustible air directly from the outside through an installation shaft or a double-walled flue gas duct. This
method has several advantages:
– The heating room doesnot need any air suction openingto the outside and therefore does not cool down.
– Lower energy consumption.
– Additional energy recovery in the flue gas duct by preheating of the combustible air.
– Dirtfrom the burner environment is not sucked in. The heating room can thus be used as a workspace, laundry room etc. at
the same time.
– Possible to install in loft areas or attic.
– Possible to install in garages.
Thecondensationthatoccursneednot,asarule,beneutralisedandcanthereforepassdirectlytodrainagethroughaplastictube.
Safety management
The entire safety management of the gascondensing boiler is managed through an electronic control panel. If there is water
shortage,gasshortageor undefinedoperatingconditions,thereisasafetyshutdown.Acorrespondingerrormessageshowsthe
technician all the necessary information needed for troubleshooting.
Electronic control
A full electronic digital control panel, together with the "intelligent" automatic firing unit for the burner, controls all the heating
and hot water functions fully automatically for the direct heating circuit, an optional connectable mixed heating circuit as well
as a storage tank charging circuit.
All settings, displays and functions are carried out by the ROTEX-THETA control. A multi-language clear text display andthe
keyboard offer multipleand comfortable options for operation.
Thegascondensingboilerflexiblyadjustsitsoutputtochangingdemands.Theheatingoutputisacontrolledsteplessmodulation
in the range 5-25 kW (A1 BG 25i) or 8-40 kW (A1 BG 40i). The flue gas temperature always remains below 90 °C.
To increase comfort, a digital room station (ROTEX THETA RS, 15 70 18) or a room controlset (THETA RFF,
15 40 70) are also available as options.
Water connection
The gas condensing boiler has a joint inflow and return flow for the heatingcircuit and storage tank charging. The connections
are placed on the rear of the unit (refer to Fig 2-3).
Condensing technology
Condensing technology makes optimum use of theenergy contained in the heating gas. The flue gas iscooled in the boiler and,
in the case of the ambient air-independent method, inthe flue gas system, until the temperature falls below the dew point. Part
ofthewatervapourcreatedoncombustionofthegastherebycondenses.Thecondensationheatisfedtotheheating,incontrast
to low-temperature boilers, thus making it possible to achieve over 100% efficiency.
The condensationin gas condensing technology has a pH value between 3.5 and 4. Thecondensation neednot therefore, as a
rule, be neutralised before being guided into the publicdrainage system.

2 xProduct description
9
BA ROTEX A1 BG Inline - 10/2007
2.3 Gas burner
Fig. 2-4 Gas burner A1 BG 25i / A1 BG 40i- Views from the front
Fig. 2-5 Gas burner A1 BG 25i / A1 BG 40i- Views from the rear Fig. 2-6 Gas burner A1 BG 25i / A1 BG 40i- Views from the left
1Burner surface
2Fan
3Safety gas control block
4Gas/air compound controller
5Gas solenoid valve (1 x class B and 1 x class C)
6Automatic gas firing unit CVBC
7Gas connection G ½" FT
8Venturi nozzle with air connection DN 50
9Measurement connection IN - inlet gas pressure
10 Measurement connection OUT - outlet gas pressure
11 Adjusting screw gas/air mixture
12 Setting screw for gas pressure control
13 Burner flange
14/1 Ionisation electrode
14/2 Ionisation cable
15/1 Ignition electrodes
15/2 Ignition cable
16 Flame tube insert
17 Burner flange seal (O-Ring)
18 Flame tube seal (flat graphite seal)
19 Fan flange seal (flat silicon seal)
20 Clamp plates Do not loosen!
21 Air suction pressure hose
22 Cover with strain relief for burner cable and locking screwfor
automatic gas firing unit

2 xProduct description
10 BA ROTEX A1 BG Inline - 10/2007
Burner setting and output limitting
Thegasburnerisfactory-setforagastype,whichisindicatedontheyellowstickeronthefanhousingoftheburner.Theburner
can be operated with the following gas types:
– Natural gas E/H
– Natural gas LL/L
– Fluid gas.
A change in the gas type can be made only by a heating engineer, because this involvesresetting of the gas burner.
The heating engineer can limit the burner output by entering parameters in the boiler switchboard.
– Thelimitingofthemaximumburneroutputwouldbeadvisable,forexample,intheeventofbettersourcingchargesforlower
installed outputs.
– The limitting of the minimum burner output is advisable if, for example, the gas resistance is relatively high and the flame
becomes unstable or if the requirements for the partial loadare not fullfilled when making calculations for theflue gas
system.
Control of the burner output
TheROTEXTHETA23RcontrolcontinuallydeterminestherequisiteinflowtemperatureandindicatesthistotheCVBCautomatic
firing units of the gas burner. The CVBC automatic firing unit calculates the necessaryburner output from the target value and
thevaluesof theinflow andreturn flowtemperaturesensors.Theburnerfanimmediatelyadjuststhegasfanspeedandassuch
the combustion air flow. The gas controller controls the gas volume accordingly.
Gas/air compound control
Thegas/fluegascompoundcontrol(pneumaticrcompound)ensuresthatthe suitableCO2-courseismaintainedforeveryoutput.
Thegas/fluegascompoundcontrolcausestheburnertoreacttoeverymodificationintheairvolumecorrentwithacorresponding
change in the gas volume current (zero pressure control).
2.4 Connection
Integrated connection group
The integrated connection group is acompact unit for connecting a heating circuit and a hot watertank to the gas condensing
boiler ROTEX A1.
The integrated circulation pump allows the requiredwater to flow through the gas condensing boiler and the active circuit (hot
water storage tank or heating circuit). The 3-way switch valveswitches between the heating circuit and thehot water storage
tank as required by the boiler control.
Temperature sensor
The gas condensing boiler has a weather-driven control for the inflow temperature. This function requires an external
temperature sensor. A 3 m flexible cable is already connected inside thedevice and placed in the control panel on the circuit
board.
The temperatures captured by the unit's internal temperature sensors (inflow and return flow temperature sensor, fluegas
temperature sensor) are used for theoutput control of the burner and for fault detection.
Ifa hotwater storagetankisused, theconnectedstorage tank temperature sensor mustbemounted atthesuitableposition
in the hot water storage tank (observe assembly instructions for the hot water storage tank).
The mixer circuit inflow sensor(TMKF, 15 60 62) is required for the control of the mixer circuit.
The electronic control recognises existing sensor configuration automatically when switching on the gas condensation boiler.
Mixer circuit (optional)
Amixer circuitcanbe connecteddirectly to thegascondensingboilersA1BG 25i/A1BG40i,controlledthroughtheelectronic
boiler control. ROTEX offers the following:
– Theready-to-connectmixergroupAMK1( 15 60 44),whichcontainsacirculationpumpintegratedintheheatinsulated
housing, a motor mixer and check valveswith temperature displays.
– The mixer circuit contact sensor TMKF ( 15 60 62).
Information about the dimensions and connecting dimensions are given in Chapter 7 "Technical data".

2 xProduct description
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BA ROTEX A1 BG Inline - 10/2007
Bycascadingfrom the heat circuit expansion modules THETA HEM1 ( 15 60 61), thesystemcanbe expandedby upto
5 mixer circuits and/or storage tank charging circuits. The required temperature sensors need tobe ordered separately (mixer
circuit contact sensor TMKF ( 15 60 62), storage tank temperature sensor TSF( 156063)).
Room control (optional)
A separate room control THETA RFF ( 15 40 70) can be connected for each heating circuit for a remotesetting of modes
and room temperature from other rooms.
Room station (optional)
All temperature valuesand modes of the control unit THETA 23R (central unit) can be displayed and changed through the room
station THETA RS ( 15 70 18). Apart from the chimney sweep and manual operationfunction, all operating elements
(display, keys, rotary switch and functions (e.g. timer programs)) are identical to those of the central unit.
The room station THETA RS can be installed ina suitable place in the building and can beused for the remote operation of the
boiler control.
2.5 Hot water storage tank (not included in scope of supply)
4 types of hot water storage tanks are available for the gas condensing boilers A1 BG 25i and A1 BG 40i (see Tab. 2-1).
Furthermore, the ROTEX Solaris System can be included in the hot water preparation.
For further information about the hot water tanks, refer todocuments for Sanicube INOX, Sanicube PEX and
Solaris.

2 xProduct description
12 BA ROTEX A1 BG Inline - 10/2007
Basic technical data for hot water storage tank
Tab. 2-1 Basic technical data of the ROTEX hot water storage tank which can be connected to the gas condensing boiler
Heating output data for hot water storage tank
Tab. 2-2 Thermal output data of the ROTEX hot water storage tankwhich can be connected to the gas condensing boiler
Type Sanicube INOX Sanicube
Solaris INOX Sanicube Solaris PEX Sub-tankforhotwater storage tank
Parameter SC 38/16/0 SCS 38/16/0 SCS 580/1 US 150
Basic data
Total storage capacity 500 Litres 500 Litres 500 Litres 148 Litres
Empty weight 84 kg 87 kg 109 kg 44 kg
Total filled weight 584 kg 587 kg 609 kg 192 kg
Dimensions (L x B x H) 79 x 79 x 159 cm 79 x 79 x 159 cm 79 x 79 x 159 cm 100 x 66 x 66 cm
Maximum permissible storage water temperature 85 °C 85 °C 85 °C 90 °C
Stand-by heatingpower 1,4 kWh/ 24h 1.4 kWh/ 24 hrs 1.4 kWh/ 24 hrs 1.1 kWh/ 24 hrs
Maximum operatingpressure 10 bar 10 bar 6 bar 10bar
Drinking water heat exchanger material Stainless steel (1.4404) Stainless steel (1.4404) PEX Pressure vessel (ES)
Water content of the heat exchanger
Drinking water heating 24.5 Litres 24.5 Litres 80 Litres 144 Litres
Storage tankcharging heat exchanger
(stainless steel) 10.4 Litres 10.4 Litres 10.4 Litres 3,3 Litres
Solar heating support (stainless steel) 2 Litres
Pipe connections
Cold and hot water 1" MT 1" MT ¾" FT ¾" FT
Heating inflow and returnflow 1" MT 1" MT 1" MT ¾" MT
Order number 16 50 16 16 45 16 16 50 06 16 01 50
Type Sanicube INOX Sanicube
Solaris INOX Sanicube Solaris PEX Sub-tankforhotwater storage tank
Parameter SC 38/16/0 SCS 38/16/0 SCS 580/1 US 150
Key performance indicator NLaccording to DIN
4708 (on recharging at 35 kW, TKW = 10°C /
TWW = 45°C / TSP = 65°C / Tv: 80°C)
4,1 2,3 3,5 2,2
Continuous rating QDaccording to DIN 4708 35 kW 35 kW 35 kW 25 kW
Hot water quantity without reheating up to
15 l/min tapping rate (TKW = 10°C /
TWW = 40°C / TSP = 60°C)
412 Litres 220 Litres 335 Litres 250 Litres
Hot water quantity with reheatingat 20 kW
reheating power and 15 l/min tapping rate
(TKW = 10°C / TWW = 40°C / TSP = 60°C)
837 Litres 442 Litres 600 Litres 300 Litres
Short time water quantity in 10 min
(TKW = 10°C / TWW = 40°C / TSP = 60°C,
Recharging output 35 kW)
300 Litres 220 Litres 250 Litres 160 Litres

3 xInitial start-up
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BA ROTEX A1 BG Inline - 10/2007
3Start-up
3.1 Safety
The following special instructions are applicable for transport, erection, installation and initial start up:
– Only lift the gas condensing boiler by the carrying straps provided for this purpose. Lifting or displacing the gas condensing
boiler by the panels can damage the unit.
– The erection surface must be firm, flatand horizontal. Install a pedestal if necessary.
– Observe requirements for the installation room (see chapter 1.5).
– The firing ordinance valid for the country andDIN 18160 are applicable for the execution and measurement of the flue gas
system. The properties of the flue gas system must be clearly evident on the system (nameplate in theinstallation room).
– Thespecialisedcompanycarryingouttheworkmustcometoanagreementwiththedistrictchimneysweepbeforebeginning
the work. We recommend documenting the participation of the district chimney sweep in aform sheet.
– Theelectrical connectionshouldonlybeperformed by electrical engineers incompliancewithvalidstandardsandguidelines
as well as the specifications of the energy supply company.
– Work on the gas-conducting parts must be carried out only by heating experts authorised and trained by thegas or energy
supply company.
– Make the gas connection according to the technical rules for gas installation as well as the relevant specifications of the
country of destination and of the gas supply company.
– The functioning of the safety temperature limiting (STB) must be testedbefore the final initial start-up and the gas burner
must be set exactly by using a flue gas analyser.
3.2 Instructions for erection
Scope of delivery
– The gas condensing boiler (pre-assembled),
– Accessories package (switch valve, T-piece, ball cocks, external temperature sensor(s), seals,double box nuts),
– Flexible condensate drain hose.
Erection versions
Thegascondensingboilersaredesignedgenerallyfortheambient-air-independentoperation.Theyarefittedwithaconcentric
fluegas/airsupplyconnectionDN80/125.ROTEXrecommendsusingthegascondensingboilerinambientair-independentmode.
If possible, choose this installation version!
In conditional ambient air-dependent andin ambient air dependent operation, the installationroommusthavea ventilation
opening of at least 150 cm2to open air. As such, the installation room will not be assigned the heated building envelope under
the Energy Conservation Ordinance (EnEV), which downgrades the energyrating of the building.
Installation height
The bottom edge of the condensateoutlet connection to the appliance must be higher than the outlet height of thecondensate
dischargehose,otherwisecondensatecandamupintheoutlet.Ifinstallingwithanextensionstoragetank,keepaboilerpedestal
height of at least 80 mm.
Dirt filter in the heating return flow
Ifthegascondensingboilerisconnectedtoaheatingsysteminwhichpipelinesorheatingbodiesofsteel,ordiffusion-permeable
floor heating pipes are inserted,slurry and chips can reach into theboiler and cause choking,local overheating or corrosion
damage. ROTEX recommends, therefore, installing a dirt filter into the heating return path.
WARNING!
A gas condensing boiler that was improperly erected and taken into service canendanger human life and
health and its functioning adversely affected.
• Erection and initial start-up of the gas calorific value boiler only by - heating experts authorised and
trained by the gas calorific value boiler company.
Incorrect start-up voids the manufacturer's guarantee for the device.
If you have any questions, please contact your heating installer or our Technical Customer Service.

3 xInitial start-up
14 BA ROTEX A1 BG Inline - 10/2007
Surface temperature
– Inambientair-independentmodewith ratedpower, thedesigndoesnotallowtemperatures>80°C on anycomponentout-
side the unit panels. Therefore, no minimum distance is required to components made with flammable materials.
– Aminimum distance of 50 mm betweentheflue gas duct and flammablecomponentsshould bemaintainedin a partial ambi-
ent air-independent and ambient air-dependent mode.
– Do not store or use highly combustible and flammable materials in the immediate vicinity of the gas condensing boiler.
Installation in garages
The gas condensing boilers A1 BG 25i and A1 BG 40i are generally suitable for installation and operation in garages.Require-
ments:
– Ambient air-independent operation,
– A durable operating manual placed in a very visible place near the boiler,
– The construction must include a protective device against mechanical damage (vehicle!) for the entire system (e.g. bracket
or deflector).
3.3 Initial start-up
After the gas condensing boiler has been erected and fullyconnected, technical staff can put it in operation.
3.4 Instructions and handover to the operator
Afterthegascondensingboilerhasbeenputintooperationbythetechnicalstaff,itishandedovertoyou.Theinstallerinstructs
you in the servicing and operation of the gas condensation boiler at thetime of the handover.
The instruction contains at least the following topics:
– Explanation of the secure and proper use of the gas condensation boiler as well as the legally binding obligations which are
binding on you asoperator of a gas heating system,
– Explanation of theoperating elements and the optional settings which you can make.
– Explanation of thepossible modes with instructions for an economic and energy-saving operation.
– Explanation of the necessary cleaning and servicing activities which you can carry out,
– Actions to take in the event of failures.
Afluegastemperaturesensorintegratedinthe controlofthegas condensingboilercausesasafetyshutdown
if the flue gas temperature is too high. No additional insulation is needed in Germany.
WARNING!
An improperly commissioned gas condensing boiler is a riskto the health and safety of individuals and can
adversely affect its functioning.
• The start-up of the gas condensing boiler mustonly be performed by heating engineers authorised and
trained by gas or energy supply companies.
The requirements and tests before the initial start-up, the activities forthe initial start-up and the necessary
tests are described in detail in the Installation and servicing manual for the technical operation.
The scope of supply includes an installation and instruction form. Document the proper handover by filling-in
this form together with the installer.

4 xOperation
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BA ROTEX A1 BG Inline - 10/2007
4Operation
4.1 Operating elements on the boiler control panel
4.1.1 Overview and brief description
All the important operating elements and electrical connections are integrated in the boiler switchboard. The electronics ensure
a smooth system operation.
Mains switch
Switching the gas condensing boiler on and off. When the heating system is on, the mains switch is illuminated green.
Collective fault signal
During normal operation, the collective fault signal is off. If it lights up this indicates a malfunction.
Pressure gauge
– Black pointer: Indication of the current water pressure in the heating system.
– Green range: Permitted water pressure range.
– Red pointer: Indication of the permitted minimum pressure.
The black pointer must be in the green range. If it is to the left of the red pointer, the water pressure must be raised by topping
up the system. If water needs to be filled frequently, please find out thereason for it and have the fault correct as soon as
possible.
Fig. 4-1 Operating elements on the boiler control panel
1Mains switch
2Collective fault signal
3Not assigned
4Pressure gauge
5Control: Central unit THETA 23R
6Rotary switch for selecting and setting functions and
parameters
7Selection of the target room day temperature
8Selection of the reduced target room temperature
9Selection of the target temperature for the hot water
storage tank
10 Selecting the mode
11 Setting Automatic timer program
12 System information
13 Emission measurement, manual operation, fault clearance
function
14 Display
15 Compartment for quick reference operating manual
16 Fixing bolts for the control
Malfunctioning is generally indicated by an error code on the display.
For troubleshooting instructions refer to Chapter 6.1 "Fault detection and troubleshooting".

4 xOperation
16 BA ROTEX A1 BG Inline - 10/2007
Control THETA 23R
Electronicdigitalcontrol ROTEX THETA23Rfor controlling2heating circuits (directheatingcircuit, mixercircuit)and a storage
tank charging circuit. It contains a switch clock with three individually configurable timer programs per heating circuit. Three
moreuserscanbeconnectedtotheTHETA23Rcontrol(alsorefertochapter2.4).Moreover,amodemcanbeconnectedthrough
telephone for mode switching over.
Rotary switch
The rotary switch can be used for selecting operating settings, changing and storing target values.
Target room temperature for the day
Selection and setting of the target temperature in normal operation. Setting according to individual temperature sensitivity.
Reduced target room temperature
Selection and setting of the target temperature ineconomy operation (night reduction). Setting according to individual temper-
ature sensitivity.
Target temperature hot water storage tank
Selection and setting of the target hot water storage tank temperature Setting according to specific hot water requirement.
Selecting the mode
Setting the mode by tapping the mode selection key. The mode currently active flashes on the display. Selection and activation
of another mode with the rotary switch. A marking on the display through the respective symbol shows the mode currently
selected.
Provisional modes:
Automatic modes
* Thisfunction is notavailable if aroom controller THETARFF isconnectedor if theoperating mode ofthe control hasbeen set on different settings for the
individual heating circuits.
• Rotate to the right (+): Increased regulation
• Rotate to the left (–): Reduced regulation
• Tapping: Saving the selected value
• Press and hold (3 sec): Enter the programming level (select level)
It is possible to trigger an unplanned storage tank charge by keeping the key pressed for a long time (during an
economy phase).
HOLIDAY Frost -protected shutdown of heating and hot water(e.g. during holidays).
ABSENT Brief break in the heating mode during absence.
PARTY Extended heating mode over and above the heating period preset in the AUTOMATIC MODE.
AUTOMATIC Automatic heating and economy mode according to timer program.
SUMMER Hot water mode according to timer program, heating switched off with frost-protection. *

4 xOperation
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Permanent modes
Setting Automatic timer program
Selection of one of 3 pre-installedtimer programs P1, P2 or P3. You canfind a detailed description for adjusting the switching
time in the "ROTEX Control“ documentation, which is included in the scope of supply of the gas calorific value boiler.
System information
Querying all system temperatures and operating statuses of the system components.
• Tap the system informationkey.
• Query the desired information successively by using the rotary switch.
Emission measurement, manual operation, fault clearance function
You can call 3functions by using these keys.
– Functionsforemissionmesurement:Tapthemanualbutton.Firsttap:theburnerrunswiththemaximumoutput,secondtap:
the burner runs with minimum output.
– Manual operation: press the manual button for 5 sec. The gas condensingboiler is controlled according to the set target
value (heat generator temperature). The storage tank charges until the maximum adjustablestorage tank temperature is
reached. It then switches over to heating.
– Faultclearance:Ifthedisplayshows"RESET",tapthemanualbutton.Ifaproblemrecurs,therootcausemustbeeliminated.
Display
Allsystemtemperaturesandoperatingstatusesofthesystemcomponentscanbeindicatedonthestandarddisplay.Intheevent
of a fault, the corresponding fault signal is issued.
Standarddisplayinnormaloperation:Currentdayoftheweek,currentdate,currenttime,heatgeneratortemperatureandactive
operating mode (marking bar).
4.1.2 Display and modification of the parameters
Standard display
Modifying parameters
All parameters for operation of the heating system can be displayed and set on the boiler switchboard.You have no access to
some of the setting areas. You are protected through an accesscode and can be called onlyby authorised specialists.
HEATING Continuous heating mode without time restriction.
REDUCED Continuous reduced heating mode without time restriction.
STAND-BY Frost-protected shutdown of heating and hot water.
This manual will provide an overview of the method for parameter modification. You can find a more detailed
descriptionofthemostimportantoperatingparametersinthebriefinstructionmanualincludedinthescopeof
supply.
The current operating parameters for the normal operation are
displayed:
Day of the week, Date, Clock time, Heat generator temperature
The marking column identifies the active mode
(Automatic, Timer program II inthe example)
Special displays:
– Ice crystal: Anti-freeze active
– Sun screen: Summer switch-off active
Fig. 4-2 Standard settings display

4 xOperation
18 BA ROTEX A1 BG Inline - 10/2007
Proceed as follows to change a parameter:
• Press the selection keys of the parameters to be set (e.g. for setting the Automatic Timer program).
• Select the parameter value by rotating the rotary switch to the left or right until the desired value is shown in the display.
• Include the selection by pressing the rotary switch.
4.2 Heating mode
Inthe normal operation,theboilertermperaturecontrolleralways worksinan Automaticorcontinuous mode.Theboiler temper-
ature is controlled in relation to weather.
4.2.1 Manual setting of the boiler temperature
Thegas condensingboilercan be controlledin manualoperationformanuallyheatingtheheating systemor for manuallysetting
the boiler temperature.
4.2.2 Pumping setting for an energy-setting operation
ThegascalorificvalueA1 BG 25ihas athree-stage pump(Fig 2-2,item 8),which hassufficientpowerasa ruleto supplyto the
complete heating system. Additional pumps are needed only if mixed heating circuits are installed.
Dependingontheheatrequirementand designtemperaturesoftheheatingsystem,thepump canalsobeoperatedatareduced
speed,without havingtocontendwithrestrictionsonthe heatsupply.Thiswill saveyoupump power.Thepumpinstalledinthe
gas calorific valueA1 BG 25i consumes about 75-80W at the power stage 3, about 50-60 Wat the power stage 2 and only
about 40 W at power stage 1.
Determination of the needed pump stage
• Determinethethroughputquantitypertainingtoacertainheatingoutput inthe heatpowergraph (Fig 4-4),dependingonthe
design scatter.
• Pressthemanualkeyonthecontrolfor
about 5 s.
ÎThe indication "Manual opera-
tion" appears on the display.
• You can now use the rotary switch to
set the desired temperature (setting
range 5 - 80 °C).
press for approx. 5 s
Target temperature
Current actual value
Modify Desired
setpoint (flashing)
Return to original operating mode, basic display,
specified setpoint is saved
Figure 4-3 Manual operation for THETA 23R (adjust temperature of heater)
Fig. 4-4 Heat output graph of the pump installed in the gas
condensing boiler A1 BG 25i Fig. 4-5 Remaining pumping height of the pump installedin the gas condensing boiler A1 BG 25i

4 xOperation
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• Determine the hydraulic resistance in the heating network.
• Determine the necessary power stage of your heating pump on the basis of the Fig 4-5.
• Set the pump for the necessary output stage.
Example for determining the pump output stage
– Heat requirement: 16.6 kW,design temperatures: 75/60°C, scatter:15K,requisitethroughputquantity:900l/m, hydraulic
resistance in the heating network: 250 mbar.
ÎAs designed, thepump stage 2 is sufficient. In the transitionperiod, even pump stage1 can suffice.
4.2.3 Tips about operating noises
Insome cases,theresonance inthefluegas system canamplifythenoise at the mouth of thefluegas duct. The noiselevelcan
be effectively reduced by using a silencer ( 15 45 78).
Air suction noisesare generated in ambient air-dependent operations. The noise level can be effectively reduced by using a
silencer ( 15 45 77).
4.3 Temporary shutdown
Thedesignscatterdescribesthetemperaturedifferencebetweentheheatinginflowandheatingreturnflowfor
design conditions (as a rule -12 °C outside air temperature).
In practice, the hydraulic resistance in the heating network is often unknown. You can observe the inflow and
return flow temperature onthe heat generator and determine if thepump still provides sufficient output at a
lower speed stage.
Thedifferencebetweentheinflowandreturnflowtemperaturemustnotincreasebeyondthedesignscatterand
each room must still heat upsufficiently.
1Heating pump
2Setting lever of the pump output stage
Fig. 4-6 Setting pump output stage
ThegascondensingboilerA1 BG 40ihasa controlledheatingpump, onwhich theheating expertmakesthe opti-
mumsettingat thetimeoftheinitialstart-up.Themanualsetting ofthepumpoutput stageis certainlyalsopos-
sible, but not necessary.
CAUTION!
A heating system which is shut down can freeze in the event of frost and may suffer damage.
• Drain the shut-down heating system if there is danger of frost.
• Iftheheatingsystemisnotdrained,thegasandpowersuppliesmustbesecuredandthemainswitchmust
remain switched on.

4 xOperation
20 BA ROTEX A1 BG Inline - 10/2007
If no heating andno hot water supply is needed over a long period, the gas condensing boiler can be temporarily shut down.
ROTEXrecommends,however,thatyou put the systemin the Stand-Bymode.The heatingsystemisthen protected from frost.
The pumps and valve protection functions are active.
If it is not possibleto guarantee the gas andpower supply when there is danger of frost,
– The gas condensing boiler must be drained,
– Suitable antifreeze measures must be adopted for the connected heating system and hot water storage tank (e.g. draining).
Drain the gas condensing boiler
• Switch off the main switch and secure against restarting.
• Close gas stopcock.
• Drain the water content of the boiler and possibly of the entire system from the filling and draining fitting (KFE-cock).
4.4 Recommissioning
Ifthegas condensingboilerhas notbeeninoperationfora fairlylong time,you mustcarry outsomepreparatoryworkandtests
when recommissioning it.
4.4.1 Work for recommissioning
Fill up condensate outlet with water
In order to prevent flue gas from escaping into the installation room, the condensate line must be filled up with water.
• Screw down the review cover of the connecting piece of the flue gas line.
• Fill the condensate line with water through a hose that is held in the fluegas pipe.
• Screw down down the review cover again in place and test thecondensate discharge section for leakage.
Filling the heating system
• Connectthefillinghosewithreturnflowstopper(½")to thefillinganddrainingfitting (KFE-cock,Fig 4-1,item 3)andsecure
it against slipping by using a hose clip.
• Open the KFE cock andobserve the pressure gauge (Fig 2-1, item 12).
• Fill the system with water until the marking of the system overpressure is roughly in the centreof the green range of the
pressure gauge display.
• Shut off the KFE cock.
• Vent the entire heating network (open the system control valves).
• Check the water pressure on the pressure gauge again and top up with waterif necessary.
• Shut the KFE cock, remove the filling hose with return flow stopper from the filling and draining fitting.
Functioning check after the initial start-up
Check the heating function after concluding thestart-up activities (see section 4.4.2).
• Switch over the control tomanual operation and set the target parameter (see section 4.2.1).
ÎThe boiler temperature and (if hot water storage tank is connected) the storage tank temperature must rise slowly.
The gas condensing boiler chargesthe storage tank until the maximum storage tank as setis reached. Thereafter, itswitches
over to heating mode.
• Check all heating conduits in hot statefor leakage.
• Set the desired mode (see section 4.1.1).
Ifnoticeany irregularitiesduringthefunctioningcheckafterthe initialstart-upor during the initialdaysofoper-
ation, contact your heating expert.