Buderus 500-24C User manual

7215 3300 – 07/2007 GB/IE (en) For the user
Please read thoroughly before operating the unit
Users manual
Gas wall hung Boiler condensing
Buderus 500-24C
Buderus 500-28C

2 Users manual for Buderus 500-24C and 500-28C • 07/2007
Buderus • http://www.buderus.co.uk Subject to modifications resulting from technical improvements
Preface
Introduction
Please read these instructions and follow them carefully for a
safe and economical use of your combi boiler.
Important general instructions for use
This device should only be used for its intended purpose and
in accordance with the regulations.
It is a requirement and in your own interest, and that of safety
that this boiler must be installed by a CORGI registered
installer, in accordance with the relevant requirements of the
current Gas Safety (Installation and Use) Regulations,
The Building Regulations, current I.E.E. Wiring Regulations
and the relevant British Standard Codes of Practise.
The device may only be used in combination with the units,
accessories and spare parts listed in the installation and
maintenance instructions.
Other combinations of units, accessories and consumables
are only to be used if they completely fulfil the specifications
involved, and if system performance and safety are not
affected in any way.
Subject to technical modifications
Constant development efforts may result in minor differences
between illustrations, functional steps and technical data.
Cleaning
For normal cleaning simply dust with a dry cloth. To remove
stubborn marks and stains, wipe with a damp cloth and soap
and finish off with a dry cloth.
DO NOT use abrasive cleaning materials.
Gas Council Aplliance No. :
Buderus 500-24C : 47-110-04
Buderus 500-28C : 47-110-03

Users manual
Users manual for Buderus 500-24C and 500-28C • 07/2007 3
Subject to modifications resulting from technical improvements Buderus • http://www.buderus.co.uk
Contents
1 Safety precautions. . . . . . . . . . . . . . . . . . . . . 4
2 Installation area / boiler room. . . . . . . . . . . . 4
3 Working in the heating system. . . . . . . . . . . 4
4 Functions of the system and operating
instructions . . . . . . . . . . . . . . . . . . . . . . . . . . 4
5 Maintenance intervals . . . . . . . . . . . . . . . . . . 4
6 Conversion to LPG . . . . . . . . . . . . . . . . . . . . 4
7 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . 4
8 Permanent clearances. . . . . . . . . . . . . . . . . . 5
9 DBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
10 Initial start-up . . . . . . . . . . . . . . . . . . . . . . . . . 7
10.1 Preparing the boiler for operation . . . . . . . . . . 7
10.2 Operational and fault codes . . . . . . . . . . . . . . . 9
11 Taking the system out of service . . . . . . . . 10
11.1 Draining the system in case of frost. . . . . . . . 10
Preface
Dear Customer,
Your Buderus 500 Series wall-mounted condensing gas
combi boiler has been designed and built in accordance with
state-of-the-art technological standards and the recognised
safety rules. Special focus has been placed on operator con-
venience in this respect.
Carefully read the safety instructions and operating manual to
ensure safe, economic and ecologically beneficial use of the
unit.
Due to the high efficiency of the boiler a plume of water vapour
may form at the terminal during operation. This is normal.

Users manual
4 Users manual for Buderus 500-24C and 500-28C • 07/2007
Buderus • http://www.buderus.co.uk Subject to modifications resulting from technical improvements
1 Safety precautions
2 Installation area / boiler room
3 Working in the heating system
It is recommended to enter into a service contract with
a specialist company.
4 Functions of the system and
operating instructions
The installer should familiarize the user with the functions and
operation of the heating system and ensure that a complete set
of technical documentation is supplied.
5 Maintenance intervals
For optimum, long-term reliable functioning of the heating
boiler, and in order to be able to claim under the terms of the
manufacturer's warranty, the heating boiler must be inspected
and maintained at least once a year (under normal operating
conditions) by an officially recognized installation and service
engineer. The term "normal operating conditions" means that
the heating boiler is used to provide central heating and/or hot
water to no more than one single-family dwelling.
In all other cases, the heating boiler must be inspected and
maintained by an officially recognised installation service engi-
neer every 2,500 burner operating hours.
6 Conversion to LPG
The boiler is suited for natural gas. To convert the boiler to
LPG you must contact a CORGI registered fitter.
7Abbreviations
DBA = Control unit (Dedicated Burner Automat)
MCW inlet = Mains Cold Water inlet
DHW outlet= Domestic Hot Water warm outlet
CH flow = Central Heating flow
CH return = Central Heating return.
IF YOU SMELL GAS:
DO NOT SMOKE OR STRIKE MATCHES
DO NOT TURN ELECTRICAL SWITCHES ON OR OFF
PUT OUT NAKED FLAMES
OPEN DOORS AND WINDOWS
KEEP PEOPLE AWAY FROM AFFECTED AREA
TURN OFF THE CONTROL VALVE AT THE GAS METER
CALL THE NATIONAL GAS EMERGENCY SERVICES,
FREE ON: 0800 111 999
NOTE
In the event of any other type of incident, shut off
the main gas supply and electric supply to the
appliance and seek assistance from a CORGI
registered engineer.
DANGER!
The air intake and outlet openings must not be
reduced in size or closed.
DANGER!
Do not store or use inflammable materials or
liquids near the heating boiler.
NOTE
To prevent the boiler from being damaged, care
must be taken not to contaminate the combustion
air with halogenated hydrocarbons (e. g. con-
tained in aerosol sprays, solvents, detergents,
paints, and adhesives), or with high quantities of
dust. The room in which the boiler is installed
must be frost-proof and be well ventilated.
DANGER!
Only a CORGI registered Engineer is to be
entrusted with the installation of this boiler, the
gas supply and the flue connection. Commission-
ing, Servicing and any Repairs must be carried
out by a competent person i.e.:
a CORGI Registered Engineer.
All CORGI Registered Installers carry a CORGI
identification card and have a registration
number. Both should be recorded in your boiler
logbook. You can check if your installer/Engineer
is registered by telephoning 01256 372300 or by
writing to:
CORGI, 1 Elmwood, Chineham Business Park,
Crockford Lane, Basingstoke. RG24 8WG.
NOTE
The heating boiler is designed exclusively for
heating water as part of a central heating system
and/or hot-water system.

Users manual
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Subject to modifications resulting from technical improvements! Buderus • http://www.buderus.co.uk
8 Permanent clearances
The boiler must be located in an area with the following
permanent clearances.
5 mm 5 mm 8 mm
21 mm21 mm
NOTE
The permanent clearances do not change if a
wall spacing frame is used.
The installer or service engineer must be able
to create sufficient service clearences. These
clearences should have been considered at
time of installation.

Users manual
6 Users manual for Buderus 500-24C and 500-28C • 07/2007
Buderus • http://www.buderus.co.uk Subject to modifications resulting from technical improvements!
9DBA
The boiler is equipped with a boiler control unit (DBA). This is
the internal control of the boiler. The DBA is located behind the
access panel.
The DBA allows you to operate the boiler and to make adjust-
ments in its settings.
DBA overview:
1. Mains switch (see fig. 1)
Use this switch to turn the boiler on or off.
2. Reset button B(see fig. 1)
When a blinking code is in the display, it is possible to try and
restart the boiler by pressing this button.
3. Service Button A(see fig. 1)
Is used for servicing purposes only.
DO NOT use this button!
4. Display (see fig. 1)
Setting, adjustments and fault codes are displayed on the DBA
(see fig. 2).
5. Menu button E(see fig. 1)
The menu button Eallows you to scroll through the menu
items.
Pressing the Ebutton once to display the current warm start
function setting.
Pressing the Ebutton twice to display the current DHW tem-
perature setting.
Pressing the Ebutton three times to display the current set-
ting of summer operation.
Pressing the Ebutton four times to display the current CH
flow temperature setting.
6. and 7. Up Cand Down Dkeys (see fig. 1)
These keys can be used for adjusting temperatures and
activating or de-activating certain summer operation.
The Ckey, when pressed, gives the current operating status
of the boiler. Press the Dkey once to display the current DHW
flow in l/m.
fig. 1 DBA
item 1: mains switch
item 2: "reset" button
item 3: "service" button
item 4: display
item 5: "menu" button
item 6: adjusting arrow up
item 7: adjusting arrow down
217
3 4 5 6
NOTE
It is not possible to reset the boiler when there
is no fault code blinking in the display.
fig. 2 DBA display

Users manual
Users manual for Buderus 500-24C and 500-28C • 07/2007 7
Subject to modifications resulting from technical improvements! Buderus • http://www.buderus.co.uk
10 Initial start-up
10.1 Preparing the boiler for operation
Please also note the user manual supplied with the
external time controls and thermostat.
10.1.1 Check water pressure
zCheck the pressure gauge (fig. 3, item 3) located at the
bottom of the boiler for the current system pressure.
Optimum system pressure is 1.5 bar.
10.1.2 Fill the heating system
The system should be filled with untreated mains water.
zTurn off the boiler by pressing the mains switch to "0".
zIf necessary open the CH flow and CH return servicing
valves (fig. 3, item 1 and 2).
zConnect filling loop (fig. 5).
zOpen both stop valves (fig. 5).
zFill the system to a pressure of approx. 1.5 bar (fig. 3,
item 3).
zClose both stop valves.
zVent the air from all radiators starting with the lowest radia-
tor and working up to the highest point.
zCheck the pressure after venting. If the pressure has
dropped under 1.0 bar then top up the system as described
previously.
zDisconnect the filling loop and cap off.
fig. 3 Servicing shut off valves
CH
flow
Gas CH
return
DHW
outlet
MCW
inlet
2
1
3
WARNING!
The wall-mounted condensing gas combi boiler
must not be activated at this stage.
fig. 4 DBA – Mains switch
1
fig. 5 Connecting filling loop
filling loop
stop
valve
stop
valve
double
check
valve
MCW
inlet CH return
NOTE
If there are frequent water losses, have the
system examined and repaired by a CORGI
registered installer. Have the inhibitor concen-
tration checked every year.

Users manual
8 Users manual for Buderus 500-24C and 500-28C • 07/2007
Buderus • http://www.buderus.co.uk Subject to modifications resulting from technical improvements!
10.1.3 Temperature-setting adjustments
Setting the warm start function
zPress Ebutton once.
zUse the Cand Dkeys to turn the warm start function on
or off (table 1). Factory setting: warm start function is "on".
Setting the domestic hot water (DHW) temperature
zPress Ebutton (see fig. 6, item 2) twice then adjust the
DHW temperature to the desired temperature (40 °C -
60 °C) using the Cand Dkeys (see fig. 6, item 1).
Factory setting is 48 °C.
Setting the boiler to summer operation
When you want to make sure that your boiler will not operate
for central heating in the summer then you can set the boiler to
summer operation. The boiler will then only operate for DHW.
zPress the Ebutton (see fig. 6, item 2) three times.
The current setting blinks.
zUse the Cand Dkeys to adjust to desired setting.
Setting the flow temperature for CH
zPress Ebutton (see fig. 6, item 2) four times then adjust
the flow temperature to the desired temperature (30 °C –
80 °C) using the Cand Dkeys (see fig. 6, item 1).
Factory setting is 80 °C.
Setting Meaning
H- ECO / cold start More energy efficient, less chance of
calcification, longer waiting periods.
I- comfort / warm start
Maximum comfort due to short
waiting period for warm water. Not as
energy efficient as the cold start and
there is more chance of calcification.
table 1 Warm start function
fig. 6 DBA – adjustment arrows
1
2
3
Central heating is on
Central heating is off (summer operation).
DHW is still available
NOTE
When summer operation is active then the
boiler will not operate for central heating until
summer operation has been deactivated.
NOTE
It is not possible to set the flow temperature
when the boiler is set to summer operation.

Users manual
Users manual for Buderus 500-24C and 500-28C • 07/2007 9
Subject to modifications resulting from technical improvements! Buderus • http://www.buderus.co.uk
10.2 Operational and fault codes
Operating conditions and possible faults can be seen, pressing
the Ckey.
All codes not contained in table 2 should be noted down
separately. These are malfunctions that require the presence
of a CORGI installer.
Display after
pressing
service
button
Meaning Rectification
0A, 0C, 0E,
0H, 0L, 0U,
0Y
Boiler is ready for
operation
6A Burner not ignited
Press Reset button B
(fig. 6, item 3). If the
burner fails to ignite after
several unblocking opera-
tions, consult a CORGI
installer.
-H Normal heating
mode
Maximum comfort when
set at 60 °C
=H Normal hot water
mode
table 2 Operational and fault codes

Users manual
10 Users manual for Buderus 500-24C and 500-28C • 07/2007
Buderus • http://www.buderus.co.uk Subject to modifications resulting from technical improvements!
11 Taking the system out of service
zTurn off the boiler by pressing the mains switch to "0" (fig. 4,
item 1).
zClose the gas service valve by turning it clockwise
(fig. 7, item 1).
Frost protection
The boiler has an automatic frost protection. When the CH flow
temperature drops below 7 °C then the boiler will start up.
11.1 Draining the system in case of frost
It is not recommended, but if the boiler needs to be shut down
for a longer period of time, then it is necessary to drain the sys-
tem. Especially when there is a chance for frost conditions.
zTurn off the boiler by pressing the mains switch to "0" (fig. 4,
item 1).
zClose the gas shut off valve (fig. 7, item 1).
zDrain the system at its lowest point using the stop valves or
radiator (see fig. 8). The automatic air vent at the system’s
highest point must be open.
fig. 7 Gas service valve
12
1: Gas valve closed
2: Gas valve open
fig. 8 Draining the system

Note
Users manual for Buderus 500-24C and 500-28C • 07/2007 11
Subject to modifications resulting from technical improvements! Buderus • http://www.buderus.co.uk

Heating system specialist:
Buderus
Cotswold Way
Warndon
Worcester
WR4 9SW
Telephone: 01905 - 752 936
Fax: 01905 - 753 130
www.buderus.co.uk
Buderus is a trading name of BBT Thermotechnology UK Ltd.
Customer Services:
Technical Product Support:
Sales:
Returns:
Spares:
Tel: 0870 - 421 5933
Tel: 0870 - 421 5944
Tel: 01905 - 752 640
Tel: 01905 - 752 531
Tel: 01905 - 752 576
Fax: 01905 - 456 445 / 455 394
Fax: 01905 - 455 392
Fax: 01905 - 754 620
721.533A - 4673 - 07/2007