United Kingdom
en
User Manual
Wall Mounted Gas Condensing Boiler
Baxi MainEco Combi and System
Combi 24-28-35 / System 18-24
Dear customer,
Thank you for purchasing this appliance.
Please read this manual carefully before using the product and keep it in a safe place for future reference.
In order to ensure continued safe and efficient operation we recommend that the product is regularly maintained. Our Service
and After Sales organization can assist with this.
We hope you will receive many years of satisfactory service.
Contents
1
Introduction ................................................................................................4
1.1
Symbols used .......................................................4
1.2
Abbreviations ........................................................4
1.3
General ..................................................................5
1.3.1
1.3.2
1.3.3
1.4
2
Certifications .........................................................6
Safety instructions and recommendations ..............................................7
2.1
Safety instructions ...............................................7
2.2
Recommendations ................................................8
2.2.1
3
Manufacturer’s liability .............................................5
Installer’s liability .....................................................5
User’s liability ..........................................................6
Benchmark Commissioning Checklist .....................8
Description ..................................................................................................9
3.1
Operating principle ...............................................9
3.1.1
3.1.2
3.1.3
3.2
Main parts ............................................................10
3.3
Clearances around the boiler ............................10
3.4
Control system ....................................................11
3.4.1
02092014 - 7621607-02
Gas/air setting .........................................................9
Combustion .............................................................9
Heating and domestic hot water production ............9
Adjustment ............................................................11
1
Contents
3.5
4
5
6
7
Operating the boiler .................................................................................12
4.1
Commissioning the boiler ..................................12
4.2
Reading the various current values ..................12
4.3
Installation shutdown .........................................13
4.4
Antifreeze protection ..........................................13
Checking and maintenance .....................................................................14
5.1
General instructions ...........................................14
5.2
Periodic checks ..................................................14
5.3
Filling the system ...............................................15
5.4
Bleeding the heating system .............................16
5.5
Draining the installation .....................................17
Troubleshooting .......................................................................................18
6.1
Error codes ..........................................................18
6.2
Incidents and solutions ......................................20
Technical specifications ..........................................................................21
7.1
8
9
Control panel .......................................................11
Technical specifications ....................................21
Energy savings .........................................................................................22
8.1
Energy-saving advice .........................................22
8.2
Room thermostat and settings ..........................22
Warranty ....................................................................................................23
9.1
General ................................................................23
9.2
Warranty terms ...................................................23
9.2.1
9.2.2
9.2.3
9.2.4
10
Warranty registration, service & repair ..................23
Benchmark Commissioning Checklist ...................23
Ways to register your warranty .............................23
Annual service .......................................................24
Appendix ...................................................................................................25
10.1 User instruction card ..........................................25
02092014 - 7621607-02
2
02092014 - 7621607-02
3
1. Introduction
1
Introduction
1.1
Symbols used
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
In these instructions, various danger levels are employed
to draw the user’s attention to particular information. In so
doing, we wish to safeguard the user’s safety, highlight
hazards and guarantee correct operation of the appliance.
DANGER
Risk of a dangerous situation causing serious
physical injury.
WARNING
Risk of a dangerous situation causing slight
physical injury.
CAUTION
Risk of material damage.
Signals important information.
¼Signals a referral to other instructions or other pages
in the instructions.
1.2
Abbreviations
4 LTH: Low temperature heating
4 DHW: Domestic hot water
4 HRU: Heat Recovery Unit
4 PCU: Primary Control Unit - Electronic system to
control burner function
4 SCU: Secondary Control Unit - Additional electronic
system
4
02092014 - 7621607-02
1. Introduction
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
1.3
General
1.3.1.
Manufacturer’s liability
Our products are manufactured in compliance with the
requirements of the various applicable European
Directives. They are therefore delivered with [ marking
and all relevant documentation.
In the interest of customers, we are continuously
endeavouring to make improvements in product quality.
All the specifications stated in this document are therefore
subject to change without notice.
Our liability as the manufacturer may not be invoked in the
following cases:
4 Failure to abide by the instructions on using the
appliance.
4 Faulty or insufficient maintenance of the appliance.
4 Failure to abide by the instructions on installing the
appliance.
1.3.2.
Installer’s liability
The installer is responsible for the installation and
commissioning of the appliance. The installer must
respect the following instructions:
4 Read and follow the instructions given in the manuals
provided with the appliance.
4 Carry out installation in compliance with the prevailing
legislation and standards.
4 Perform the initial start up and carry out any checks
necessary.
4 Explain the installation to the user.
4 If a maintenance is necessary, warn the user of the
obligation to check the appliance and maintain it in
good working order.
4 Give all the instruction manuals to the user.
02092014 - 7621607-02
5
1. Introduction
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
1.3.3.
User’s liability
To guarantee optimum operation of the appliance, the
user must respect the following instructions:
4 Read and follow the instructions given in the manuals
provided with the appliance.
4 Call on qualified professionals to carry out installation
and initial start up.
4 Get your installer to explain your installation to you.
4 Ensure the Appliance is serviced in accordance with
the manufacturer’s instructions by a suitable qualified
person.
4 Keep the instruction manuals in good condition close
to the appliance.
This appliance is not intended to be used by persons
(including children) whose physcial, sensory or mental
capacity is impaired or persons with no experience or
knowledge, unless they have the benefit, through the
intermediary of a person responsible for their safety, of
supervision or prior instructions regarding use of the
appliance. Care should be taken to ensure that children
do not play with the appliance.
If the mains power lead is damaged it must be replaced
by the original manufacturer, the manufacturer’s dealer or
another competent person to prevent hazardous
situations.
1.4
Certifications
CE identification no
PIN 0063CM3019
NOx classification
5 (Standards EN)
Type of connection (Flue gas outlet) C13, C33, C53
Gas Council number
6
MainEco Combi 24: 47–075–93
MainEco Combi 28: 47–075–94
MainEco Combi 35: 47–075–95
MainEco System 18: 41–470–13
MainEco System 24: 41–470–14
02092014 - 7621607-02
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
2. Safety instructions and recommendations
2
Safety instructions and
recommendations
2.1
Safety instructions
DANGER
If you smell gas:
1.
2.
3.
4.
5.
Do not use a naked flame, do not smoke, do not
operate electrical contacts or switches ( doorbell,
light, motor, lift, etc..).
Shut off the gas supply.
Open the windows.
Evacuate the premises.
Call your fitter.
DANGER
If you smell flue gases:
1.
2.
3.
4.
Switch the appliance off.
Open the windows.
Evacuate the premises.
Call your fitter.
WARNING
Depending on the settings of the appliance:
4
4
4
The temperature of the flue gas conduits may exceed
60°C.
The temperature of the radiators may reach 85°C.
The temperature of the domestic hot water may reach
65°C.
CAUTION
Do not neglect to service the appliance:
4 For completely safe and optimum operation, you
must have your boiler regularly serviced by an
approved installer.
02092014 - 7621607-02
7
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
2. Safety instructions and recommendations
2.2
Recommendations
WARNING
Only qualified professionals are authorised to work on the
appliance and the installation.
4 Regularly check the water pressure in the installation (minimum
pressure 0.8 bar, recommended pressure between 1 and 2 bar).
4 Keep the appliance accessible at all times.
4 Never remove or cover labels and rating plates affixed to the
appliance. Labels and rating plates must be legible throughout the
entire lifetime of the appliance.
4 The appliance should be on Summer or Antrifreeze mode rather
than switched off to guarantee the following functions:
- Anti blocking of pumps
- Antifreeze protection
2.2.1.
Benchmark Commissioning Checklist
Please ensure that the installer has fully completed the Benchmark
Checklist on the inside back pages of the installation instructions
supplied with the product and that you have signed it to say that you
have received a full and clear explanation of its operation. The
installer is legally required to complete a commissioning checklist as
a means of complying with the appropriate Building Regulations
(England and Wales).
All installations must be notified, by the installer, to Local Area
Building Control either directly or through a Competent Persons
Scheme. A Building Regulations Compliance Certificate will then be
issued to the customer who should, on receipt, write the Notification
Number on the Benchmark Checklist.
This product should be serviced annually to optimise its safety,
efficiency and performance. The service engineer should complete
the relevant section of the Benchmark Service Record in the
Installation & Service manual after each service.
The completed Benchmark Checklist & proof of annual servicing
(where applicable) will be required in the event of any warranty work.
8
02092014 - 7621607-02
3. Description
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
3
Description
3.1
Operating principle
3.1.1.
Gas/air setting
The casing fitted to the boiler is also used as an air box. Air is sucked
in by the fan and gas injected into the venturi by the fan intake. The
fan rotation speed is set according to the settings parameters, the
thermal energy requirement and the temperatures measured by the
temperature sensors. The gas and air are mixed in the venturi. The
gas/air ratio ensures that the quantities of gas and air are adjusted to
each other. This provides optimum combustion on the entire output
range. The gas/air mixture is fed into the burner on top of the
exchanger.
3.1.2.
Combustion
The burner heats the heating water circulating in the heat
exchanger. At a return temperature lower than around 55°C, the flue
gases cool down to a temperature lower than the dew point, thus
causing the condensation of the water vapour contained in the flue
gases in the lower section of the heat exchanger. The heat released
during this condensation process (the latent heat or condensing heat)
is also transferred to the heating water. The cooled combustion gases
are evacuated via the combustion gas outlet flue. The condensation
water is evacuated via a condensate trap.
3.1.3.
Heating and domestic hot water production
On combi boilers, an integrated plate exchanger heats the domestic
water. A 3-way valve determines whether the heated water is fed into
the heating system or the plate exchanger. A pick-up sensor signals
that a hot water tap is being opened. This signal is transmitted to the
control panel, which then switches the 3-way valve to the hot water
position and trips the heating pump. The 3-way valve is spring-loaded
but only consumes electricity when it switches to another position.
The heating water reheats the domestic water in the plate
exchanger. In comfort mode, if there is no hot water draw-off, the
boiler handles the periodic reheating of the plate exchanger. Any
limescale particles are kept out of the plate exchanger by a selfcleaning water filter (self-cleans once every 76 hours).
02092014 - 7621607-02
9
3. Description
3.2
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
Main parts
1
2
15
3
4
14
5
6
13
7
12
Flue gas outlet/Air intake (Combustion air/flue gas
adapter 60/100)
2
Casing/air box
3
Outlet for measuring combustion gases
4
Ignition/ionization electrode
5
Flue gas discharge pipe
6
Gas/air system with a fan, gas block and automatic burner
unit
7
Air intake silencer
8
Plate heat exchanger (DHW) (Only for Combi models)
9
Connection box
10
Condensate trap
11
11
Circulation pump
10
12
3-way valve
13
Primary heat exchanger
14
Expansion vessel
15
Automatic air vent
8
9
T004783-A
3.3
1
Clearances around the boiler
5
5
36
(1)
8
5
≥2
55
0
10
0
Clearance when operating
(2)
Clearance for maintenance
00
4
≥2
36
(1)
50
4
(2)
R000698-A
10
02092014 - 7621607-02
3. Description
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
3.4
Control system
3.4.1.
Adjustment
The power of the boiler can be adjusted in the following ways:
4 On/Off setting
The output between the minimum and maximum values varies
based on the heating flow set point temperature.
4 Adjustable control
The output between the minimum and maximum values varies
based on the heating flow temperature determined by the
modulating control system.
3.5
Control panel
MainEco Combi 24 - 28 - 35
1
2
3
4
T002247-D
1
Domestic hot water temperature rotary knob
2
Heating water temperature rotary knob
3
Sweep key B and Status signals
4
RESET-button and on/off signal
MainEco System 18 - 24
1
2
3
4
R000714-A
1
No function
2
Heating water temperature rotary knob
3
Sweep key B and Status signals
4
RESET-button and on/off signal
The instrument panel for the connection box has 2 push buttons with
signals. The signals provide information about the operating condition
of the boiler. The RESET button lights up green when the boiler is
connected to the mains. The status signal for the B button can flash
in a range of colours and at different frequencies. The meaning of
these signals can be found in the User instruction card supplied with
the boiler. ¼See also: "User instruction card", page 25
CAUTION
The instruction card must be slid underneath the
connection box after the boiler installation or use of the
card.
The instrument panel for the connection box also has 2 rotary
knobs. The N rotary knob can be used to set the temperature of the
domestic hot water. The D rotary knob can be used to set the
maximum flow temperature of the heating water. The heating/
domestic hot water function can be switched off by turning the rotary
knob to position off.
02092014 - 7621607-02
11
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
4. Operating the boiler
4
Operating the boiler
4.1
Commissioning the boiler
1. Check the water pressure in the heating system.
If the water pressure is lower than 0.8 bar, more water
should be added. If necessary, top up the water level in the
heating system (recommended hydraulic pressure
between 1 and 2 bar).
¼See chapter: "Filling the system", page 15
2. Open the gas valve on the boiler.
3. Turn the boiler on.
4. The boiler will begin an automatic venting-programme (which lasts
approx. 4 minutes) and will do this every time the power supply is
isolated. Both push buttons on the instrument panel light up green
during the venting cycle.
The current operating condition of the boiler is shown by the status
signal on the instrument panel. The status signal for the B button
can flash in a range of colours and at different frequencies. The
meaning of these signals can be found in the User instruction card
supplied with the boiler.
See also:
¼ "User instruction card", page 25
¼ "Error codes", page 18
4.2
Reading the various current values
Boiler status information can be read using a suitable controller. The
following current values can be read off the information menu Q:
4 State.
4 Sub-status.
4 Flow temperature (°C).
4 Return temperature (°C).
4 Calorifier temperature (°C).
4 Outside temperature (°C) (Only with an outside temperature
sensor).
4 Solar boiler temperature (°C).
4 Ionization current (µA).
4 Fan speed in rpm.
4 Water pressure (bar (MPa)).
4 Supplied relative heat output (%).
12
02092014 - 7621607-02
4. Operating the boiler
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
4.3
Installation shutdown
If the central heating system is not used for a long period, we
recommend switching the boiler off.
4 Switch off the boiler electrical power supply.
4 Shut off the gas supply.
4 Ensure that the boiler and system are protected against frost
damage.
4.4
Antifreeze protection
CAUTION
Drain the boiler and central heating system if you are not
going to use your home or the building for a long time and
there is a chance of frost.
Set the temperature control low, for example at 10°C.
To prevent radiators and the system from freezing in rooms where
there is a risk of frost (e.g. a garage or storage room), a frost
thermostat or outside sensor can be connected to the boiler.
CAUTION
4
4
4
4
The antifreeze protection does not function if the
boiler is switched off.
The integrated protection system only protects the
boiler, not the installation.
Open the valves on all radiators connected to the
heating system
If the boiler has been placed in a room at risk of frost,
the condensate drain and condensate trap should
preferably be protected against freezing with a frost
protection cable.
When the heating water temperature in the boiler falls by too much,
the integrated protection system in the boiler starts up. This protection
functions as follows:
4 If the water temperature is lower than 7°C, the heating pump starts
up.
4 If the water temperature is lower than 4°C, the boiler starts up.
4 If the water temperature is higher than 10°C, the boiler shuts down
and the circulation pump continues to run for a short time.
02092014 - 7621607-02
13
5. Checking and maintenance
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
5
Checking and maintenance
5.1
General instructions
WARNING
4
Maintenance operations must be done by a qualified
engineer.
An annual inspection is compulsory.
4
Only original spare parts must be used.
4
4 Carry out the inspection and standard maintenance operations
once a year.
4 Carry out specific maintenance operations if necessary.
CAUTION
4
Maintenance operations must be done by a qualified
engineer.
We recommend taking out a maintenance contract.
4
Only original spare parts must be used.
4
5.2
Periodic checks
4 Check the water pressure in the installation.
If the water pressure is lower than 0.8 bar, more water
should be added. If necessary, top up the water level in the
heating system (recommended hydraulic pressure
between 1 and 2 bar).
¼See chapter: "Filling the system", page 15.
4 Carry out a visual check for the presence of any water leaks.
4 Open and close the radiator valves several times a year (this
prevents the valves from seizing up).
4 Clean the outside of the boiler using a damp cloth and a light
detergent.
1
2
CAUTION
3
4
T000181-B
14
Only a GasSafe Registered Installer is authorised to clean
the inside of the boiler.
02092014 - 7621607-02
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
5.3
5. Checking and maintenance
Filling the system
Topping up without a refilling device:
1. Use the pressure gauge to check the water pressure in the heating
system.
2
If the water pressure is lower than 0.8 bar, more water
should be added. If necessary, top up the water level in the
heating system (recommended hydraulic pressure
between 1 and 2 bar).
1
2
3
4
3
2. Open the valves on all radiators connected to the heating system.
3. Set the room thermostat to as low a temperature as possible.
4. Wait until the temperature drops below 40°C and the radiators
seem cold before filling the central heating system.
5. To fill with water, use a filling tube with two tap connections, a rag
and a bleed key.
6. Connect the filling tube to a (cold) water tap.
7. Eliminate the air from the filling tube. Slowly fill the tube with
water. Hold the end of the tube up, above a bucket. Turn off the
tap as soon as water runs out of the pipe.
8. Unscrew the plug from the filling/draw-off valve.
4
5
7
6
8
9
10
14
The filling/draw-off valve is not necessarily located next to
the boiler.
9. Attach the tube to the filling/draw-off valve. Firmly tighten the nut
on the filling tube.
10.Open the filling/draw-off valve on the heating system.
11.Open the running water tap.
12.Use the pressure gauge to check the water pressure in the heating
system.
13.Close the water tap when the water pressure reaches 2 bar.
14.Close the filling/draw-off valve on the heating system. Leave the
tube on the filling/draw-off valve until the air is purged from the
installation.
When water is added, air gets into the heating system:
4 Degas the installation.
4
4
AD-3000483-A
4
After the air has been vented, the water pressure can
drop below the required level.
Use the pressure gauge to check the water pressure
in the heating system.
If the water pressure is lower than 0.8 bar, more water
should be added.
15.After filling the installation, switch the boiler on.
Filling and bleeding the installation 2 times a year should
be sufficient to obtain an adequate hydraulic pressure. If it
is often necessary to top up the installation with water,
contact your fitter.
02092014 - 7621607-02
15
5. Checking and maintenance
5.4
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
Bleeding the heating system
It is essential that you bleed any air in the heating system to prevent
the annoying noises likely to be produced during heating or when
tapping water. To do this, proceed as follows:
1
1.
2.
3.
4.
5.
6.
7.
Open the valves on all radiators connected to the heating system.
Set the room thermostat as high as possible.
Wait until the radiators are hot.
Switch the boiler off.
Wait around 10 minutes until the radiators are cold.
Bleed the radiators. Start with the lower floors.
Open the bleed connection using the bleed key provided whilst
keeping a rag pressed against the connection.
8. Wait until water comes out of the bleed valve and then close the
bleed connection.
1
2
3
4
2
3
11
5
CAUTION
4
The water may still be hot.
9. Switch on the boiler. A vent cycle of a duration of around 3 minutes
is carried out automatically.
10.After venting, check whether the pressure in the installation is still
sufficient.
6
C
A
B
If the water pressure is lower than 0.8 bar, more water
should be added. If necessary, top up the water level in the
heating system (recommended hydraulic pressure
between 1 and 2 bar).
¼See chapter: "Filling the system", page 15
11.Set the room thermostat or the regulator.
7
8
R000712-A
16
02092014 - 7621607-02
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
5.5
5. Checking and maintenance
Draining the installation
It may become necessary to empty the water from the heating system
when the radiators have to be replaced, should there be a major water
leak or a risk of frost. To do this, proceed as follows:
1
1.
2.
3.
4.
Open the valves on all radiators connected to the heating system.
Switch off the boiler electrical power supply.
Wait around 10 minutes until the radiators are cold.
Connect an evacuation hose to the plug located at the lowest
level. Place the end of the hose in a discharge sump or in a place
where the water discharged from the valve can not do any
damage.
5. Open the filling/draw-off valve on the heating system. Vent the
heating installation.
1
2
3
4
3
2
WARNING
The water may still be hot.
6. When no more water comes out of the drainage plug, close the
drainage valve.
5
After draining the concentration of system corrosion
inhibitor and anti-freeze may become excessively diluted seek advice from your installer.
4
R000730-A
02092014 - 7621607-02
17
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
6. Troubleshooting
6
Troubleshooting
6.1
Error codes
In the event of a fault, the status signal for the B button flashes
red. The meaning of the error codes is given in the error table:
Status signals
Description
Error code 1
Sensor error
(1 times red signal)
Code(1)
e[02 / e[03 / e[04 / e[05 / e[06 / e[07 / e[08 /
e[09 / e[10 / e[11 / e[35
Error code 2
Overheat temperature protection e[12 / e[41
(2 times red signal)
Error code 3
Ignition fault
(3 times red signal)
e[14 / e[16 / e[36
Error code 4
Fan fault
(4 times red signal)
e[34
Error code 5
Parameter error
(5 times red signal)
e[00 / e[01
Error code 6
Miscellaneous
(6 times red signal)
e[17 / e[37 / e[38 / e[39 / e[40 / e[41
(1) The code can be read using a suitable controller.
If one of the above mentioned error codes is shown, proceed as
follows:
4 Check the water pressure in the heating system.
- The water pressure is higher than 0,8 bar. Degas the
installation.
- The water pressure is lower than 0,8 bar. Fill the system with
clean tap water (advised water pressure is between 1,5 and 2
bar).
4 Check that the gas valve is fully opened.
- Open the gas valve if it is closed.
Press the J key for 5 seconds: The status signals will
flash red quickly and the boiler will start its reset
procedure. The boiler will also start an automatic venting
cycle lasting around 4 minutes. If the error code continues
to display, contact the installer.
Before contacting the installer. Note the following information:
4 Error code
4 Boiler type
18
02092014 - 7621607-02
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
6. Troubleshooting
If your installer confirms that the fault is with the boiler, simply call
heateam on 0844 871 1525.
Before contacting heateam, please have the following information to
hand:
4 Serial no. of the appliance
R000694-A
4 Installer’s name and address
4 Proof of purchase (if you do not have the serial number)
Our service division heateam is open:
4
Monday to Friday 8am - 6pm
4
Weekends and Bank Holidays 8.30am - 2pm,
excluding Christmas Day and New Year’s Day
To ensure the highest level of customer service, heateam will text to
you your engineer appointment details if you provide a mobile phone
number. Following your engineer visit, we will ask you to rate your
level of satisfaction with our service via text message.
02092014 - 7621607-02
19
6. Troubleshooting
6.2
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
Incidents and solutions
Problem
There is no domestic hot water.
Probable causes
Solution
4
Check that the boiler is switched on.
The boiler is not switched on.
4
Check the fuses and switches.
The DHW mode is deactivated.
4
Check that the gas valve is fully opened.
Activate the DHW mode using a suitable controller.
The water pressure is too low (<
0.8 bar).
Top up the installation with water.
The energy-saving shower head is
restricting the water flow.
Clean the shower head; replace if necessary.
Increase the temperature setting by using the rotary
The DHW temperature setting is too
knob on the control panel or by using a suitable
low.
controller.
The radiators are cold.
The heating temperature setting is
too low.
Increase the value of parameter p1 using a suitable
controller or, if a room thermostat is connected increase
the temperature.
The heating mode is deactivated.
Activate the heating mode using a suitable controller.
The radiator valves are closed.
Open the valves on all radiators connected to the
heating system.
The boiler is not switched on.
Check the fuses and switches.
4
Check that the gas valve is fully opened.
The heating water temperature
setting is too low.
Increase the temperature setting by using the rotary
knob on the control panel or by using a suitable
controller.
The heating temperature setting is
too low.
Increase the value of parameter p1 using a suitable
controller or, if a room thermostat is connected increase
the temperature.
The water pressure is too low (<
0.8 bar).
The gas pressure is too low.
4
Check that the boiler is switched on.
4
Check the fuses and switches.
Top up the installation with water.
4
Press the Reset button for 2 seconds.
4
Correct the error if possible.
Check that the gas valve is fully opened. Open the gas
valve.
Not enough water in the installation. Top up the installation with water.
Water leak.
Significant variations in domestic
Insufficient water supply.
hot water temperature.
Clicking in the central heating
pipes.
4
Top up the installation with water.
An error code appears on the
display.
The water pressure is too low (<
0.8 bar).
Check that the boiler is switched on.
The water pressure is too low (<
0.8 bar).
No power supply.
The boiler is not working.
4
Contact the fitter.
Open the valve.
The central heating pipe
connections are too tight.
Contact the fitter.
There is air in the heating pipes.
It is essential that you bleed any air in the calorifier, the
conduits or the taps to prevent the annoying noises
likely to be produced during heating or when tapping
water.
The water is circulating too quickly in
Contact the fitter.
the central heating system.
Significant water leak under or
close to the boiler.
20
The boiler or central heating pipes
are damaged.
4
Close the water supply.
4
Contact the fitter.
02092014 - 7621607-02
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
7. Technical specifications
7
Technical specifications
7.1
Technical specifications
Boiler type
MainEco
Combi 24 Combi 28 Combi 35 System 18 System 24
Input control
Adjustable
Modulating(1), Start/Stop
Nominal output (Pn)
Heating System (80/60 °C)
min - max
kW
Factory setting
kW
19.5
Nominal output (Pn)
DHW System
min - max
kW
5.5 - 23.4
Factory setting
Data on the gases and combustion gases
kW
23.4
Gas consumption G20
max
m3/h
General
5.5 - 19.5
5.5 - 23.4
7.7 - 29.2
5.5 - 17.7
5.5 - 23.4
19.5
29.2
17.7
23.4
5.5 - 27.5
7.7 - 33.9
-
-
27.5
33.9
-
-
2.54
2.98
3.68
1.90
2.54
NOx annual emission (n=1)
Characteristics of the heating circuit
mg/kWh
53
58
52
41
58
Water content
l
1.6
1.6
1.7
1.4
1.4
Water operating pressure
minimum
bar
0.8
0.8
0.8
0.8
0.8
Water operating pressure (PMS)
maximum
bar
2.5
2.5
2.5
2.5
2.5
Water temperature
maximum
°C
110
110
110
110
110
Operating temperature
maximum
Characteristics of the domestic hot water circuit
°C
90
90
90
90
90
Specific hot water flow Rate 35 °C Rise
Flow rate
threshold(2)
Operating pressure (Pmw)
Electrical characteristics
l/min
9.8
11.4
14.3
-
-
minimum
l/min
1.2
1.2
1.2
-
-
maximum
bar
8
8
8
-
-
VAC
230
230
230
230
230
W
105
117
145
92
103
Power supply voltage
Power consumption - Full load
maximum
Electrical protection index
IP
X4D(3)
Other characteristics
Weight (empty)
Acoustic level at 1 metre
Total
kg
26
26
28.5
25
24.5
maximum Heating System dB(A)
38
38
42
38
40
maximum DHW System
40
42
45
-
-
dB(A)
(1) A modulating boiler adapts the quantity of heat produced to the heat required in a flexible manner
(2) Minimum quantity of water coming out of the valve to start up the boiler
(3) Splash-proof; under certain conditions, the boiler can be installed in a wet room such as a bathroom
02092014 - 7621607-02
21
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
8. Energy savings
8
Energy savings
8.1
Energy-saving advice
4 Keep the room in which the boiler is installed well ventilated.
4 Do not block ventilation outlets.
4 Do not cover the radiators. Do not hang curtains in front of the
radiators.
4 Install reflective panels behind the radiators to prevent heat
losses.
4 Insulate the pipes in rooms that are not heated (cellars and lofts).
4 Close the radiators in rooms not in use.
4 Do not run hot (or cold) water pointlessly.
4 Install a water-saving shower head to save up to 40 % energy.
4 Take showers rather than baths. A bath consumes twice as much
water and energy.
8.2
Room thermostat and settings
The room thermostat is available in the following versions:
4 2-wire ON/OFF thermostat
4 Modulating thermostat
4 Programmable room temperature thermostat
The type of thermostat and its settings have a considerable influence
on energy consumption.
A few tips:
4 A modulating thermostat, possibly in combination with
thermostatic valve radiators, saves energy and offers
considerable comfort. This combination allows you to set the
temperature on each flow. In the room in which the room
thermostat is installed, do not fit thermostatic valve radiators.
4 Completely closing and opening thermostatic valve radiators
causes undesirable temperature fluctuations. Open and close
thermostatic valves in small steps.
4 Lower the thermostat to around 20°C. This reduces heating costs
and energy consumption.
4 Lower the room thermostat when you air the rooms.
4 When setting an hourly programmable thermostat, keep in mind
the days you are absent or on vacation.
22
02092014 - 7621607-02
9. Warranty
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
9
Warranty
9.1
General
Baxi would like to thank you for buying one of our appliances and for
your trust in our product. In order to ensure continued safe and
efficient operation it is essential that the product is regularly inspected
and maintained. Your installer, annual service provider or our service
division heateam can assist with this.
9.2
Warranty terms
9.2.1.
Warranty registration, service & repair
For the warranty to be activated and maintained, please make sure:
4 Benchmark Checklist is completed by your installer
4 Warranty is registered with Baxi
4 The boiler has an annual service
Please be aware that if you do not activate your warranty,
a basic one year warranty will apply. For full terms and
conditions, visit www.baxi.co.uk/terms.
9.2.2.
Benchmark Commissioning Checklist
This checklist will be completed by your installer and records whether
the boiler has been installed correctly. This checklist can be found at
the back of the Installation and Service Manual and should be
retained over the life of the boiler.
9.2.3.
Ways to register your warranty
If your boiler is eligible for a promotional warranty, your installer will
register the product on your behalf and will provide you with the
relevant documentation. In such cases, there is no further action
required on your part.
For a standard two year warranty, please use one of the following
methods:
4 Telephone 0800 013 7989
4 Register online at www.baxi.co.uk/registration
4 Return the enclosed registration card
02092014 - 7621607-02
23
9. Warranty
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
9.2.4.
Annual service
An annual service must be completed every 12 months from the date
of installation. This service must be completed by:
4 Your Gas Safe registered installer; or
4 Our service division heateam (Telephone 0844 871 1525); or
4 Another Gas Safe registered engineer
24
02092014 - 7621607-02
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
10. Appendix
10 Appendix
10.1 User instruction card
R000392-A
Group
Signal
Meaning
Boiler in service
(Intermittent green signal)
Central heating heat
Maintenance message(1)
(Flashing orange signal)
Code A
Hot tap water
Code B
Code C
Blockage
(Flashing green signal)
Temperature protection
Shutdown input
Flame loss
Communication fault
Parameter error
Miscellaneous
Repair
(Flashing red signal)
Sensor error
Overheat temperature protection
Ignition fault
Fan fault
Parameter error
Miscellaneous
Reinitialisation
Resetting...
Chimney-sweeping position
(Intermittent orange signal)
Part load
Full load Central heating heat
Full load Hot tap water
PC programming mode
_________________________________
_________________________________
(1) This function is not applicable to every type
02092014 - 7621607-02
25
10. Appendix
26
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
02092014 - 7621607-02
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
02092014 - 7621607-02
10. Appendix
27
10. Appendix
28
Baxi MainEco Combi and System 24 - 28 - 35 / 18 -24
02092014 - 7621607-02
© Copyright
All technical and technological information contained in these technical instructions, as well as any drawings and technical de
scriptions supplied, remain our property and shall not be multiplied without our prior consent in writing. Subject to alterations.
For Baxi Customer Support,
contact us at
0844
871 1525
Please note calls may be monitored or recorded
www.baxi.co.uk
Register now to activate your warranty:
www.baxi.co.uk/registration
For the warranty to be maintained, please make sure...
1
2
3
Benchmark checklist is completed
Warranty is registered with Baxi
The boiler has an annual service
For full terms and conditions, visit www.baxi.co.uk/terms
Book your service or repair online:
www.baxi.co.uk/booking
Baxi, Brooks House
Coventry Road, Warwick, CV34 4LL.
e&oe
All descriptions and illustrations provided in this document have been
carefully prepared but we reserve the right to make changes and
improvements in our products which may affect the accuracy of the
information contained in this leaflet. All goods are sold subject to our
standard Conditions of Sale which are available on request.
7621607 - v.02 - 02092014
7621607