andrews MAXXflo EVO Lite Manual

Andrews. Built to perform.
Please read and understand these instructions before commencing installation and leave this manual with the customer for future reference.
M9943
MAXXfl o EVO Lite
High effi ciency condensing stainless steel direct storage water heater
SC15/201, SC25/201, SC35/201, SC45/201
INSTALLATION AND MAINTENANCE MANUAL

Andrews Water Heaters
Reproduction of any information in this publication by any
method is not permitted unless prior written approval has been
obtained from Andrews Water Heaters.
Andrews Storage Water Heaters have been designed and
manufactured to comply with current international standards of
safety. In the interests of the health and safety of personnel
and the continued safe, reliable operation of the equipment,
safe working practices must be employed at all times. The at-
tention of UK users is drawn to their responsibilities under the
Health and Safety Regulations 1993.
All installation and service on Andrews Water Heaters must be
carried out by properly qualifi ed personnel and, therefore, no
liability can be accepted for any damage or malfunction caused
as a result of intervention by unauthorised personnel.
Andrews Water Heaters’ policy is one of continuous product
improvement and, therefore, the information in this manual,
whilst completely up to date at the time of publication, may be
subject to revision without prior notice.
Further information and assistance can be obtained from:
Customer Support
Monday - Friday
8am - 5pm
Sales: 0345 070 1055
Technical: 0345 070 1057
Website: www.andrewswaterheaters.co.uk
Twitter: @andrewsWH
© Copyright Andrews Water Heaters 2022

Contents
1 Safety
1.1 General safety instructions ................................................................................................
1.2 Recommendations .............................................................................................................
1.3 Specifi c safety instructions .................................................................................................
1.3.1 Additional guidelines ................................................................................................
1.4 Liabilities .............................................................................................................................
1.4.1 Manufacturer’s liability ...............................................................................................
1.4.2 Installer’s liability ........................................................................................................
1.4.3 User’s liability .............................................................................................................
2 About this manual
2.1 General ..............................................................................................................................
2.2 Additional documentation ...................................................................................................
2.3 Symbols used in this manual .............................................................................................
3 Technical specifi cations
3.1 Homologations
3.1.1 Certifi cations ..............................................................................................................
3.1.2 Unit categories ...........................................................................................................
3.1.3 Factory test ................................................................................................................
3.2 Technical data ....................................................................................................................
3.3 Dimensions and connections .............................................................................................
3.4 Electrical diagram ...............................................................................................................
.
4 Description of the product
4.1 General description ............................................................................................................
4.2 Operating principle .............................................................................................................
4.2.1 Combustion and condensate gains ..........................................................................
4.2.2 Control system .........................................................................................................
4.2.3 Gas / air regulation ...................................................................................................
4.3 Main components ...............................................................................................................
4.3.1 Water heater components ........................................................................................
4.4 Control panel description ...................................................................................................
4.4.1 Control panel display ...............................................................................................
4.5 Standard delivery ..............................................................................................................
4.5.1 List of standard items included with heater ..............................................................
4.6 Accessories and options ...................................................................................................
4.6.1 Unvented system kit .................................................................................................
4.6.2 Expansion module ...................................................................................................
4.6.3 Return sensor kit ......................................................................................................
4.6.4 Modbus communication device ...............................................................................
4.6.5 Web server ..............................................................................................................
4.6.6 Anti-vacuum valve ....................................................................................................
4.6.7 Castor assembly kit ..................................................................................................
4.6.8 300 litre DHW buff er tank ........................................................................................
4.6.9 Flue backfl ow prevention kit ....................................................................................
4.6.10 Heat exchanger fl ushing kit ...................................................................................
4.6.11 Maintenance kit .....................................................................................................
4.6.12 Paint touch up kit ....................................................................................................
5 Before installation
5.1 Installation regulations ........................................................................................................
5.2 Installation requirements .....................................................................................................
5.2.1 Gas supply ................................................................................................................
5.2.2 Electricity supply .......................................................................................................
5.2.3 Water quality (and treatment) ...................................................................................
5.3 Choice of location
5.3.1 Checking the data plate ...........................................................................................
5.3.2 Location requirements .............................................................................................
5.4 Transportation & unpacking ...............................................................................................
5.5 Positioning the heater ........................................................................................................
5.6 Connection Diagrams
5.6.1 Secondary return pump Q4 .....................................................................................
5.6.2 Two heaters fi tted in parallel ....................................................................................
5.6.3 With SS300-10 Buff er tank ......................................................................................
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Contents
6 Installation
6.1 General ..............................................................................................................................
6.2 Preparation
6.2.1 Front cover removal .................................................................................................
6.3 Water connections
6.3.1 Connecting the cold water system ..........................................................................
6.3.2 Water systems ..........................................................................................................
6.3.3 Anti-vacuum valve ...................................................................................................
6.3.4 Unvented system .....................................................................................................
6.3.5 De-stratifi cation pump ..............................................................................................
6.3.6 Pressure relief valves ..............................................................................................
6.3.7 Secondary return system ........................................................................................
6.3.8 Condensate connection ...........................................................................................
6.4 Gas connections
6.4.1 Gas supply & pipe work ...........................................................................................
6.5 Air supply / fl ue gas outlet connections
6.5.1 General requirements ..............................................................................................
6.5.2 Material ....................................................................................................................
6.5.3 B23 General ventilation requirements ......................................................................
6.5.4 B23 Ventilation in a room or space ............................................................................
6.5.5 B23 Ventilation in a compartment via an internal adjoining space ..............................
6.5.6 B23 Ventilation in a compartment ventilated direct to outside ...................................
6.5.7 B23 Flue terminal positions ........................................................................................
6.5.8 C13 C33 C53 C63 General requirements .......................................................................
6.5.9 C13 C33 C53 C63 Ventilation requirements .................................................................
6.5.10 C13 C33 C53 C63 Flue terminal positions .................................................................
6.5.11 Flue parts available ................................................................................................
6.5.12 Vertical fl ue set up .................................................................................................
6.5.13 Horizontal fl ue set up .............................................................................................
6.5.14 80/125 concentric fl ue dimensions ........................................................................
6.5.15 Maximum fl ue lengths ...........................................................................................
6.6 Electrical connections
6.6.1 General requirements ...............................................................................................
6.6.2 Terminal connections ...............................................................................................
6.6.3 BMS connections - Basic .......................................................................................
6.6.4 BMS connections - Modbus ....................................................................................
6.7 Filling the installation
6.7.1 Filling the condensate trap ......................................................................................
6.7.2 Filling the system .....................................................................................................
7 Commissioning
7.1 General ............................................................................................................................
7.2 Commissioning procedure
7.2.1 Preparing the burner ................................................................................................
7.2.2 Activate Chimney Sweep function .............................................................................
7.2.3 Checking the CO2 rate .............................................................................................
7.2.4 Adjusting the CO2 rate ..............................................................................................
7.2.5 Checking the gas rate ..............................................................................................
7.3 Gas settings
7.3.1 Conversion from Natural gas (G20) to Propane (G31) ............................................
7.4 Final instructions
7.4.1 Setting the clock and DHW time program ................................................................
7.4.2 Cleaning the heater ..................................................................................................
7.4.3 User handover .........................................................................................................
8 Operation
8.1 General ..............................................................................................................................
8.2 Use of the control panel ....................................................................................................
8.2.1 Main function pages .................................................................................................
8.2.2 Information bar symbols ..........................................................................................
8.2 Frost protection ...................................................................................................................
8.3 Anti-legionella function .....................................................................................................
8.3.1 General information .................................................................................................
8.3.2 Anti-legionella settings .............................................................................................
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Contents
9 Settings
9.1 List of parameters .............................................................................................................
9.2 Setting the parameters .....................................................................................................
9.2.1 Logging into Engineer mode ...................................................................................
9.2.2 Accessing complete parameter list ........................................................................
10 Maintenance
10.1 General ...........................................................................................................................
10.2 Maintenance message ...................................................................................................
10.2.1 Resetting the maintenance message ....................................................................
10.3 Standard inspection and maintenance operations ..........................................................
10.3.1 Minimum service requirements .............................................................................
10.3.2 Inspect and clean burner assembly .......................................................................
10.3.3 Cleaning out condensate trap ................................................................................
10.3.4 Ionisation and spark electrode inspection (burner removed) ................................
10.3.5 Re-assembly of burner ..........................................................................................
10.3.6 Ionisation and spark electrode inspection (burner not removed) ...........................
10.3.7 Flue outlet seals inspection ...................................................................................
10.3.8 Condensate pipework and syphon trap ................................................................
10.3.9 Gas rate and combustion .....................................................................................
10.3.10 Inspect and fl ush DHW storage tank ...................................................................
10.4 Specifi c inspection and maintenance operations
10.4.1 General ..................................................................................................................
10.4.2 Flue temperature sensor (B8) ................................................................................
10.4.3 DHW tank temperature sensor (B3) ......................................................................
10.4.4 LMS14 Control PCB ...............................................................................................
10.4.5 GUI screen .............................................................................................................
10.4.6 Spark generator .....................................................................................................
10.4.7 Internal overheat protection device ........................................................................
10.4.8 Fan .........................................................................................................................
10.4.9 Gas valve ...............................................................................................................
10.4.10 Electrodes ............................................................................................................
10.4.11 Circulation pump ..................................................................................................
10.4.12 Heat exchanger ...................................................................................................
11 Troubleshooting
11.1 Error codes ......................................................................................................................
11.2 Error memory ..................................................................................................................
11.2.1 Accessing error history ...........................................................................................
11.3 Fault fi nding .....................................................................................................................
11.3.1 Burner control phase ..............................................................................................
12 Decommissioning, removal recycling
12.1 Decommissioning and recommissioning .........................................................................
12.1.1 Decommissioning procedure ..................................................................................
12.1.2 Recommissioning procedure ..................................................................................
12.2 Removal & recycling .........................................................................................................
13 Spare parts
13.1 Tank and sundry spares ..................................................................................................
13.2 Cover spares ....................................................................................................................
13.3 General component spares ..............................................................................................
13.4 Drain & fl ue spares ..........................................................................................................
13.5 Heat engine spares .........................................................................................................
13.6 Wiring centre spares .......................................................................................................
13.7 Copper spares ................................................................................................................
Appendix
ErP Technical data ..................................................................................................................
Product Fiche ..........................................................................................................................
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1 Safety 6 MAXXfl o EVO Lite
1 Safety
1.1 General safety instructions
Danger
If you smell gas:
1. Do not use naked fl ames, do not smoke and do not operate
electrical contacts or switches (lighting, motor, lift etc)
2. Shut off the gas supply
3. Open the windows
4. Trace possible leaks and seal them off immediately
5. If the leak is upstream of the gas meter, notify the gas
supplier.
Danger
Danger to life.
Observe warnings affi xed to this heater. Incorrect operation
of this heater could lead to considerable damage.
Danger
Commissioning should only be carried out by an approved
installer . The installer checks the tightness of the gas supply,
control and safety equipment and ensures that the combustion
values are correct. If this work is not carried out correctly there
is a risk of harm to persons, the environment and property.
Danger
Risk of poisoning:
Never use condensate as drinking water. Condensate is not
suitable for consumption by people or animals. Avoid contact
with skin.
Danger
This heater is not intended for use by persons under the age
of 12, or persons with reduced physical, sensory or mental
capabilities, lack of experience or knowledge. Only users given
supervision or instruction concerning the safe operation of this
heater and understand the hazards involved should be operat-
ing this appliance. Children should be supervised to ensure
that they do not play with the heater.
Danger
Unauthorised conversions and modifi cations to this heater are
not permitted, as these can put persons in danger and could
cause damage to the water heater. Failure to comply with
these instructions renders the warrantee for the heater void.

1 Safety 7 MAXXfl o EVO Lite
Danger
Do not store any explosive or highly fl ammable materials
close to the heater.
Warning
Risk of burns!
Be careful when using domestic hot water. Depending on the
heater settings the temperature of the hot water can rise above
65OC.
To protect from injury, you should install approved mixing
valves in the water system to reduce water temperature at the
outlet.
For safety reasons the discharge pipe from the safety valve
must always be open so that water can escape during an
emergency overheat situation.
Warning
The use of the heater and the installation by you must be
limited to the operations described in this manual. All other ac-
tions may only be undertaken by a qualifi ed engineer.
Warning
The condensation drain must not be changed or sealed. If a
condensate neutralisation system is used, they system must
be cleaned regularly in accordance with the instructions pro-
vided by the manufacturer.
Caution
Ensure that the heater is regularly serviced. Contact a qualifi ed
installer/engineer or arrange a maintenance contract for the
servicing of the heater.
Caution
Only genuine spare parts may be used, fi tted by a qualifi ed
engineer.
Caution
Secure against unintentional switch on. When the DHW tank is
empty, ensure that the heater cannot be switched on acciden-
tally.
Caution If there is a danger of freezing do not shut the gas
supply or power off to the heater. This will allow the frost pro-
tection systems of the heater to operate provided the heater is
not in a fault condition.
Caution
Do not drill holes in the casing of the appliance or fi x wiring or
isolating switches to the front cover. The cover of the appliance
is removable for maintenance and forms part of the combus-
tion air channel supplying the burner.

1 Safety 8 MAXXfl o EVO Lite
1.2 Recommendations
Removal and disposal of the water heater must be carried out
by a qualifi ed installer in accordance with local and national
regulations.
If the mains lead is damaged, it must be replaced by the
original manufacturer, the manufacturer’s dealer or another
suitably skilled person to prevent hazardous situations from
arising.
Always disconnect the mains supply and isolate from the gas
supply before working on the heater.
For safety reason, we recommend fi tting gas leak and CO
alarms at suitable places in the building in which the heater is
installed.
Check the entire system for leaks after maintenance and serv-
icing work.
Keep this document near to the heater
Only remove the casing for maintenance and repair operations.
Refi t all panels when maintenance work and servicing are
complete.
Instruction and warning labels must never be removed or cov-
ered and must be clearly legible throughout the entire service
life of the heater. Damaged or illegible instructions and warning
stickers must be replaced immediately.
Modifi cations to the heater require the written approval of
Andrews Water Heaters.

1 Safety 9 MAXXfl o EVO Lite
1.3 Specifi c safety instructions
1.4 Liabilities
1.3.1 Additional guidelines
In addition to the legal requirements and guidelines, the supplemen-
tary guidelines in this manual must also be followed. Supplements
or subsequent regulations and guidelines that are valid at the time of
installation shall apply to all regulations and guidelines specifi ed in this
manual.
1.4.1 Manufacturer’s liability
Our products are manufactured in compliance with the requirements of
the various Regulations and Directives applicable. They are therefore
delivered with UKCA/CE marking and any documents necessary. In the
interests of the quality of our products, we strive constantly to improve
them. We therefore reserve the right to modify the specifi cations given
in this document.
Our liability as manufacturer may not be invoked in the following cases:
• Failure to abide by the instructions on installing and maintaining
the appliance.
• Failure to abide by the instructions on using the appliance.
• Faulty or insuffi cient maintenance of the appliance.
1.4.2 Installer’s liability
The installer is responsible for the installation and initial commissioning
of the appliance. The installer must observe the following instructions:
• Read and follow the instructions given in the manuals provided
with the appliance.
• Install the appliance in compliance with prevailing legislation and
standards.
• Carry out initial commissioning and any checks necessary.
• Explain the installation to the user.
• If maintenance is necessary, warn the user of the obligation to
check the appliance and keep it in good working order.
• Give all the instruction manuals to the user.
1.4.3 User’s liability
To guarantee optimum operation of the system, you must abide by
the following instructions:
• Read and follow the instructions given in the manuals provided
with the appliance.
• Call on a qualifi ed professional to carry out installation and initial
commissioning.
• Get your installer to explain your installation to you.
• Have the required inspections and maintenance carried out by a
qualifi ed installer.
• Keep the instruction manuals in good condition close to the appli-
ance.

2 About this manual 10 MAXXfl o EVO Lite
2 About this manual
2.1 General
2.2 Additional documentation
2.3 Symbols used in this manual
This manual describes the installation, use and maintenance of a
MAXXfl o EVO Lite Water Heater. This manual is part of all the docu-
mentation supplied with the heater.
The following documentation is available in addition to this manual:
• User operating instruction manual
• Quick start guide
This manual uses various danger levels to draw attention to special
instructions. We do this to improve user safety, to prevent problems
and to guarantee correct operation of the appliance.
Danger
Risk of dangerous situations that may result in serious
personal injury
Danger of electric shock
Risk of electric shock
Warning
Risk of dangerous situations that may result in minor
personal injury
Caution
Risk of material damage
Important
Please note: important information
See
Reference to other sources of information

3 Technical specifi cations 11 MAXXfl o EVO Lite
3 Technical specifi cations
3.1 Homologations
Tab .2
3.1.1 Certifi cations
Tab.1
UKCA Product Identifi cation Number 0558DM2335
CE Product Identifi cation Number 0558DM2335
Class NOx(1) 6
Type of fl ue gas connection B
23
(2)
C 13 , C 33 , C 53 , C 63
(1) EN 15502-1
(2) When installing a heater with B
23 fl ue, a gas alarm must be fi tted
(2) When installing a heater with B
23 fl ue, a CO alarm must be fi tted
3.1.2 Unit categories
3.1.3 Factory test
Before leaving the factory, each water heater is optimally set and
tested for:
• Electrical safety.
• Adjustment of CO2.
• Water tightness.
• Gas tightness.
• Parameter setting.
• Functional operation.
Country Category Gas type Connection pressure
Great Britain
& Ireland
I2H
I3P
II2H3P
G20
G31
G20 / G31 (Propane)
20 mbar
37 mbar
20 / 37 mbar

3 Technical specifi cations 12 MAXXfl o EVO Lite
3.2 Technical data
Tab. 3 General performance data
Tab. 4 G20 performance data
Tab. 5 G31 performance data
Tab. 6 Electrical data
Tab. 7 Hot water data
Unit SC15 SC25 SC35 SC45
Heat input - gross (min - max) kW 6.1 - 15.0 10.7 - 25.0 10.7 - 35.0 10.7 - 45.0
Heat input - net (min - max) kW 5.5 - 13.5 9.6 - 22.5 9.6 - 31.5 9.6 - 40.5
Output (min - max) kW 6.0 - 14.7 10.5 - 24.5 10.5 - 34.4 10.5 - 44.2
NOx (EN 89) GCV mg/kwh 25 29 25 30
NOx class (EN 89) 6
Unit SC15 SC25 SC35 SC45
Electrical connection 230 V~ / 50Hz max 5.0A
Power consumption - max load (Watts) W 66 84 100 125
Power consumption - standby (Watts) W 4.5
Electrical protection index IP IP20
Unit SC15 SC25 SC35 SC45
Thermal standby losses kWh/day 1.68
Approximate heat-up time (DT = 50OC) minutes 52 31 22 17
Recovery time through 50OC l/hr 232 386 541 695
Recovery time through 56OC l/hr 207 345 483 621
Maximum operating DHW temperature OC65
Unit SC15 SC25 SC35 SC45
Gas inlet pressure permitted range mbar 30 - 50
Gas consumption (min - max) m3/h 0.23 - 0.57 0.38 - 0.94 0.38 - 1.32 0.38 - 1.69
Gas consumption (min - max) kg/h 0.42 - 1.04 0.75 - 1.74 0.75 - 2.44 0.75 - 3.13
Max gas input CO2 % 10.0 % (+/- 0.2%) 10.1 % (+/- 0.2%)
CO at maximum output ppm 21 21 53 92
Unit SC15 SC25 SC35 SC45
Gas inlet pressure permitted range mbar 17 - 25
Gas consumption (min - max) m3/h 0.59 - 1.43 1.02 - 2.40 1.02 - 3.34 1.02 - 4.25
Max gas input CO2 % 9.0 % (+/- 0.2%)
Expected CO at maximum output ppm 24 25 46 84

3 Technical specifi cations 13 MAXXfl o EVO Lite
Tab. 9 Flue data
Tab. 10 Weight data
Tab. 12 Other data
Unit SC15 SC25 SC35 SC45
Flue connection single mm 80
Flue connection concentric mm 80 / 125
Max fl ue equivalent length (single) B23 m 40
Max fl ue equivalent length (concentric) C13, C33 m 20
Max fl ue equivalent length (twin) C53 m 35
Flue gas mass fl ow rate @ 60OC (G20) kg/h 9.0 - 22.2 15.8 - 37.0 15.8 - 51.8 15.8 - 66.6
Flue gas volume @ 60OC (G20) m3/h 9.6 - 22.6 16.8 - 37.7 16.8 - 52.7 16.8 - 67.8
Max delivery pressure at fl ue gas outlet Pa 18 35 70 120
Flue gas temperature (60OC setpoint) OC 45 - 56
Max allowable fl ue pressure diff erence Pa 78 95 130 185
Max condensate production l/h 1.5 2.5 3.5 4.5
Unit SC15 SC25 SC35 SC45
Sound pressure level LpA - 1m away (free fi eld) dB(A) 37 42 47 51
Sound power level LWA - according (EN 15036-1) dB(A) 48 53 57 62
PMS Inlet / Operating pressure min (max) bar 1.2 (6.0)
Water inlet / outlet connections BSP 1 1/2”
Water return connection BSP 1”
Gas connection BSP 3/4”
Condensate connection mm 41 (Polypipe)
Tank drain connection mm 22mm
Temperature & Pressure valve connections mm 22 28
Service clearance - Above mm 400
Service clearance - Left mm 300
Service clearance - Right mm 0
Service clearance - Front mm 600
Service clearance - Rear mm 0
Unit SC15 SC25 SC35 SC45
Weight (including packaging) kg 170 173
Weight installed (empty) kg 118 120
Weight installed (water fi lled) kg 321 324

3 Technical specifi cations 14 MAXXfl o EVO Lite
3.3 Dimensions & connections
1453
727
602
97
1448
913
468
349
249
GAS INLET
0.75" BSP (f)
(Isolation valve with
inlet measuring point
supplied loose with unit)
CONCENTRIC FLUE/AIR
Ø80mm / Ø125mm
670
CONDENSATE TRAP
Ø41mm
LH Side
Cover
TANK DRAIN
Ø22mm ISOLATION VALVE
REMOVABLE PLATE FOR
ACCESS TO TANK SENSOR,
INTERNAL TANK ISOLATION
VALVE & TANK CONNECTION
INSPECTION (INSIDE UNIT)
602
DATA LABEL
TANK INSPECTION
HATCH
9191
PT VALVE 7 BAR
Ø22mm - 15kW & 25kW units
Ø28mm - 35kW & 45kW units
928
301
MCWS
1.5" BSP (m)
CABLE ENTRY POINT
4x HOLES FOR
M20 CABLE GLAND
261
497
209
172
299
1 x PLUGGED OUTLETS
1" BSP (f)
USER DISPLAY
885
SECONDARY
RETURN
1" BSP (m)
DHW
1.5" BSP (m)
1353
PT VALVE EXIT
CHECK VALVE

3 Technical specifi cations 15 MAXXfl o EVO Lite
3.4 Electrical diagram
+
0
%;
%;
8
0
/
1
4;
4;
4;
1
1

4 Description of the product 16 MAXXfl o EVO Lite
4 Description of the product
4.1 General description
4.2 Operating Principle
This Andrews Water Heater is a gas fi red, low NOx, direct fi red water
heater, with an integrated stainless steel tank. Fully automatic electronic
controls are integrated into the heater, with a wide range of control strate-
gies and sensors
4.2.1 Combustion and condensate gains
The burner heats the primary water fl owing through the heat exchanger.
If the temperature of the fl ue gases is lower than the dew point (approx.
55°C), water vapour condenses inside the heat exchanger. The energy
released during this condensation process (referred to as latent heat) is
also transferred to the primary water. The cooled fl ue gases are dis-
charged through the fl ue gas discharge pipe. The condensed water is
discharged through a siphon.
4.2.2 Control system
The fl ow (or charging) temperature is continuously monitored by the
controls and the burner along with the pump are modulated to maintain
a precise fl ow temperature from the heat exchanger into the DHW tank.
Multi-layers of control level thresholds, ensure the heater operates safely
at all times.
The electronic control system ensures that your water heating system
is smart and reliable. This means that the heater responds practically to
negative environmental infl uences (such as limited water fl ow or high fl ue
temperatures). In the event of such adverse infl uences, the controls will
seek to modulate back the burner in the fi rst instance, applying a lockout
condition if all other control methods have not been eff ective.
4.2.3 Gas/air regulation
The heater is equipped with a casing that also serves as an air box. The
fan draws the combustion air from within the casing, which is supplied
via the chosen fl ue system. The gas is injected into the venturi and mixed
with the combustion air. The fan speed is controlled on the basis of the
settings, the heat demand and the prevailing temperatures measured by
the temperature sensors. The gas/air ratio control ensures an accurate
mixture of the required amounts of gas and air. This provides optimum
combustion over the entire heat input range at all times. The gas/air mix-
ture goes to the burner, where it is ignited by the ignition electrode.

4 Description of the product 17 MAXXfl o EVO Lite
4.3 Main components
4.3.1 Water heater components
1. Hot water outlet
2. Return water inlet
3. Cold water inlet
4. DHW tank
5. Controller
6. GUI Display
7. Combustion fan
8. Circulation pump
9. Condensate trap
10. Tank sensor well (behind plate)
11. Internal tank isolation valve (behind plate)
12. DHW tank drain point
13. Check valve assembly
14. Gas connection
15. Flue connection
16. Heat exchanger
17. Air intake
18. Gas valve and venturi
1
2
314
4
5
6
15
16
17
18
7
8
9
12
10
11
13

4 Description of the product 18 MAXXfl o EVO Lite
4.4 Control panel description
4.4.1 Control panel display
The control knob is used to operate the Graphical User Interface.
Press the control knob inwards to press ENTER
See section 8.1 for details
Graphical
display
DHW temp 1 58.9 oC
Rotary selection
Press to ENTER
RESET under
plastic cover
Critical information bar
Back / ESC

4 Description of the product 19 MAXXfl o EVO Lite
4.5 Standard delivery
4.5.1 Items included with standard package
List of standard items as part of water heater package:
• MAXXfl o EVO Lite water heater
• Upper gas union (for connection to gas supply)
• Gas shutoff valve with pressure tapping point
• Tundish
• ErP energy label
• LPG conversion kit and labels
• Installation and maintenance manual
• User operation manual
• Quick start guide

4 Description of the product 20 MAXXfl o EVO Lite
4.6 Accessories and options
4.6.1 Unvented system kit
Designed to complement the heaters performance it enables the
heater to be connected directly to the cold water supply and is suitable
for an average sized pipework system. The kit (part number 7799195)
contains the following items:
• Cold water inlet control valve (set to 3.5 bar with 6.0 PRV)
• 24 ltr Expansion vessel and wall fi xings
• Continuous circulation valve (Anti-legionella device that prevents
the expansion vessel becoming a dead leg)
4.6.2 Expansion module
This expansion module can be used to add additional functions to the
heater and its system (for example adding the 300 litre buff er tank). A
module consists of:
• 3 freely confi gured relay outputs
• 2 freely confi gured temperature sensor inputs
• 1 multipurpose input
The module kit (part number 7720070) is available from Andrews Wa-
ter Heaters.
4.6.3 Return sensor kit
This strap-on temperature sensor kit is designed for mounting onto the
DHW return pipe to acquire the temperature of the water fl owing in-
side. The strap-on sensor consists of a plastic housing with a snap on
cover and can be connected to a pipe having a diameter of between
15 mm and 100 mm. The Return sensor kit (part number 7720071) is
available from Andrews Water Heaters.
4.6.4 Modbus communication module
Device used to enable direct two way communication with a Building
Management system. This device plugs directly into the heater control
PCB and translates the internal boiler protocol language into Modbus.
The module kit (part number 7720069) is available from Andrews Wa-
ter Heaters.