Ariston NUOS FSi 250 User guide

1
1
InstructionsforInstallation,
Servicingand Use
ExternalAir Source Heat Pump Water Heater
Country of Destination: GB/IE
NUOS FS 200
NUOS FSi 250

2
The NUOS External Source Air Heat Pump Water Heater is intended for DOMESTIC USE ONLY.
The NUOS is supplied in two cartons:-
Carton 1 contains the NUOS appliance.
Carton 2 contains the fittings kit.
Check labels on the cartons to ensure correct NUOS unit has been delivered BEFORE opening the
cartons.
The cardboard cartons which protect the unit should not be removed until installation.
Store the wrapped unit upright in a safe dry space away from frost until required.
Do not stack goods on the carton.
Do not dispose of the carton until AFTER installation.
The carton can be recycled.
RECOMMENDED LIFTING
Model NUOS Weight Fittings Kit kg (max)
NUOS FS 200 90 5
NUOS FSi 250 110 6.5
It is recommended to use a sack barrow for lifting and moving the packaged NUOS.
The bottom and top of the carton has polystyrene padding to protect the unit.
Carrying the NUOS will require two fit persons.
IMPORTANT
The appliance should be kept in a vertical position when transported or stored. During
manual handling it can be carried at an angle (i.e. in a sack barrow) or horizontally.
If handling entails moving the product in a position other than vertical, wait at least 3
hours before starting the appliance once it is in the correct vertical position. This will
ensure that the lubricating oil in the refrigeration circuit is correctly placed in order to
avoid the compressor becoming damaged.
IMPORTANT
Failure to follow these instructions correctly may invalidate the guarantee.
IMPORTANT
The NUOS External Air Source Heat Pump Water Heater is an UNVENTED HOT WATER
SYSTEM.
Unvented domestic hot water heating systems must be installed to comply with the current
Building Regulations, British Standards and any applicable local regulations.
IMPORTANT
Hard Water. Where the mains total water hardness exceeds 200 ppm, provision should be
made to treat the feed water to reduce the rate of limescale accumulation.
IMPORTANT - The Benchmark Scheme
Benchmark places responsibilities on both manufacturers and installers.
The purpose is to ensure that customers are provided with the correct equipment for their
needs,thatitisinstalled, commissioned and serviced in accordance with the manufacturer’s
instructions by competent persons and that it meets the requirements of the appropriate
Building Regulations. The Benchmark Checklist can be used to demonstrate compliance
with Building Regulations and should be provided to the customer for future reference.
Installers are required to carry out installation, commissioning and servicing work in
accordance with the Benchmark Code of Practice which is available from the Heating and
Hot Water Industry Council who manage and promote the Scheme.
Visit www.centralheating.co.uk for more information.
IMPORTANT PLEASE READ

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TABLE OF CONTENTS
IMPORTANT INFORMATION..................... 2
1. GENERAL INFORMATION................ 4
1.1 GUARANTEE .......................................... 4
1.2 INTENDED USE....................................... 4
1.3 PERSONAL RESPONSIBILITY ...................... 4
1.4 CE MARKING ........................................ 5
1.5 THIS MANUAL ........................................ 5
1.6 BASIC PRINCIPLES OF AHEAT PUMP.......... 6
1.7 EFFICIENCY ........................................... 6
1.8 TYPICAL INSTALLATIONS ........................... 7
1.9 NUOS COMPONENTS IDENTIFICATION........ 8
1.10 GENERAL LAYOUT .................................. 9
1.11 STORAGE VESSEL .................................. 9
1.12 HEATING ELEMENT ................................. 9
1.13 SUPPLY AIR........................................... 9
1.14 EXHAUST AIR ........................................ 9
2. SAFETY........................................... 10
2.1 FLOOR MOUNTING ................................ 10
2.2 ELECTRICAL ........................................ 10
2.3 UNVENTED .......................................... 10
2.4 PERSONAL PROTECTION ........................ 10
2.5 TRANSPORTATION ................................. 10
2.6 REFRIGERANT ...................................... 10
3. USER INSTRUCTIONS................... 11
3.1 CONTROL PANEL .................................. 11
3.2 TURNING NUOS ON............................ 12
3.3 DEFAULT SETTINGS............................... 12
3.4 SETTING DESIRED TEMPERATURE ............ 12
3.5 SETTING OPERATING MODE ................... 13
3.6 USER SETTING PROCEDURES ................. 14
3.7 SUMMARY OF NUOS OPERATION ........... 14
3.8 INFORMATION MENU .............................. 15
4. INSTALLER’S SETTINGS ............... 16
4.1 INSTALLERS MENU ................................ 16
5. TECHNICAL DATA .......................... 17
5.1 DIMENSIONS ........................................ 17
5.2 TECHNICAL DATA .................................. 18
5.3 KIT CONTENTS..................................... 19
5.4 PRODUCT LABEL .................................. 20
5.5 REGULATIONS ...................................... 20
5.6 WATER REGULATIONS ........................... 20
5.7 BUILDING REGULATIONS......................... 20
5.8 IEE WIRING REGULATIONS/BRITISH
STANDARDS......................................... 20
5.9 WIRING LAYOUT ................................... 21
5.10 MAINBOARD LAYOUT ............................. 22
6. INSTALLATION................................ 23
6.1 LOCATION OF THE APPLIANCE ................. 23
6.2 AIR SUPPLY ........................................ 23
6.3 EXHAUST AIR ...................................... 24
6.4 AIR DUCT STATIC LOSS ........................ 24
6.5 INSTALLING PROCEDURE ........................ 25
6.6 ELECTRICAL CONNECTION ...................... 25
6.7 BATHROOM ZONES ............................... 26
6.8 COMBINATION VALVE ............................. 26
6.9 WATER CONNECTIONS .......................... 27
6.10 EXPANSION VESSEL INSTALLATION ........... 27
6.11 FSI250 SOLAR CONNECTION................ 28
6.12 FSI250 BOILER CONNECTION ............... 30
6.13 TPRV & PRV DISCHARGE ................... 31
6.14 TPRV & PRV DISCHARGE TOGULLY.... 31
6.15 BUILDING REGULATIONS G3................... 31
6.16 NUOS EXPANSION DISCHARGE ............. 33
6.17 SUPPORTING FLOOR ............................. 34
6.18 POSITIONING THE UNIT .......................... 34
6.19 LEVELLING THE UNIT ............................. 34
6.20 FIXING THE UNIT .................................. 34
6.21 CONDENSATE OUTLET ........................... 34
6.22 FILLING THE SYSTEM............................. 35
6.23 DRAINING THE NUOS CYLINDER UNIT .... 35
7. COMMISSIONING SYSTEM ........... 36
7.1 COMMISSIONING PROCEDURE ................. 36
8. MAINTENANCE............................... 38
8.1 REMOVING & REPLACING ELECTRIC
HEATER ELEMENT ................................ 38
8.2 ROUTINE MAINTENANCE ........................ 39
8.3 ERROR CODES .................................... 40
8.4 FAULT FINDING .................................... 41
9. BENCHMARK LOGBOOK............... 42
TERMS AND CONDITIONS OF GUARANTEE .......... 44
LEAVE THESE INSTRUCTIONS
WITH THE END USER

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1. GENERAL
INFORMATION This manual is an integral and essential part of the product. It should be
kept with the product.
Pleaseread carefully theinstructions and notesaboutAristonNUOS Heat
Pump Water Heater contained in this manual as they provide important
information regarding the safe installation of the system.
WARNING
Warnings emphasize that a potentially hazardous or
dangerous situation could exist. Serious injury or death is
possible if warning instructions are not obeyed.
CAUTION
Indicatesprecautionsthat if not takencouldresultindamage,
malfunction, or abnormal operation of the equipment.
IMPORTANT
Text headed ‘Important’refers to vital information that should
be noted about the equipment, its use, maintenance or
warranty.
NOTE
Notes are used to give additional information, understanding or to
highlight a certain point. They may also be used for referrals.
The Ariston External Air Source Heat Pump Water Heater is guaranteed
for 5 Years (Tank) and 2 Years (electrical components) against
manufacturing defect - see terms and conditions of guarantee on back
page.
The manufacturers shall not be held liable for any damage due to faulty
installation, improper or incorrect use or uses that are not reasonably
predictable.
The guarantee is subject to:
1. Theappliancebeingcorrectlyinstalledandcommissioned,asdetailed
in this manual.
2. The appliance being annually serviced as detailed in this manual.
This appliance is intended for the production of domestic hot water at
temperaturesup to 65°C. Theappliance mustbe correctly connectedto a
domestic cold mains water supply. Electric power is required.
Theappliancemustnotbeusedforanyotherpurposeorindustrialprocess.
Themanufacturerisresponsiblefor the product’sconformitytotherelevant
constructiondirectives,lawsandregulationsin force at the timetheproduct
is first commercialised. The Plumbing Engineer/Electrician/Installer and
userareeach exclusively responsibleintheirrespective fields, forknowing
andobservingthelegal requirementsandtechnical regulations concerning
the design, installation, operation and maintenance of the appliance.
Referenceto laws, regulationsor technical specificationscontainedin this
manual is purely for information purposes; any new laws introduced or
modifications to existing laws are not in any way binding on the
manufacturer towards third parties.
1.1 GUARANTEE
1.2 INTENDED USE
1.3 PERSONAL RESPONSIBILITY

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The CE marking applied to the appliance certifies that it conforms to the
essential requirements of the following European Directives:-
2006/95/EC concerning the safety of electrical equipment.
2004/108/EC concerning electromagnetic compatibility.
Checksarecarriedoutinconformitywiththefollowingtechnicalstandards:-
EN 255-3; EN 60335-1; EN 60335-2-21; EN 60335-2-40;
EN 55014-1; EN 61000-3-2; EN 61000-3-3; EN 50366.
The manufacturer’s ability to manufacture and supply all products in
conformity with the above mentioned regulations is guaranteed by a
company quality management system that is certified according to the
ISO 9001 2008 standard.
This NUOS manual is intended for:-
1. The installer
2. The end user.
The manual is an integral and essential part of the product. It should be
kept with the appliance so that it can be consulted by the user and/or
authorisedpersonnel.
To ensure that the appliance is installed and used properly and safely,
both the installers and user must carefully read the instructions and
precautionscontainedinthismanualas they provideimportantinformation
for both their areas of competence, regarding safety, installation, use and
maintenance of the appliance.
This manual is divided into sections.
Section 1 General Information
This section is intended for both installers and users of the NUOS. It
containsgeneralinformationforthe appliance, layout anddescription
plus important information about the manual.
Section 2 Safety
Section 3 User Instructions
The Installer, once the system is operating correctly, should
demonstrate the NUOS operation with the aid of this section.
Section 4 Installer’s Settings
Installer’s control parameter settings.
Section 5 Technical Data
Generallyintended forthe specifier andinstallersincluding technical
data, dimensions and special requirements.
Section 6 Installation
Includes information for the installing Plumbing Engineer and
Electrician.
Section 7 Commissioning System
Essentialinformation forthe installer for thecompletion ofthe NUOS
installation.
Section 8 Maintenance
Includes maintenance and fault finding.
Section 9 Benchmark Logbook
1.5 THIS MANUAL
1.4 CE MARKING

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1.6 BASIC PRINCIPLES OFA
HEAT PUMP
FIG. 1.6ABASIC PRINCIPLES
Within the heat pump the refrigerant is warmed from its cooled state to
the ambient or external air temperature. This heat gain is largely free
energy.
Electricityisusedtopowerthefanwhich draws air, andalsothecompressor
which pressurises the refrigerant to increase it’s heat. Asmall amount of
electricity is also required to run the heat pump’s control system.
The efficiency of a heat pump cycle is stated by its Coefficient of
Performance (COP) value. This is a ratio between the energy produced
by the heat pump to the electrical energy supplied to it. For example a
COP of 3.0 indicates that for every 1kW of electricity used the heat pump
will produce 3.0 kW of hot water, therefore giving 2.0kW of free energy.
1.7 EFFICIENCY
FAN
The fan draws air through
the heat exchanger.
The cool refrigerant is
heated by the ambient or
external air temperature.
The refrigerant boils and
turns to vapour.
The compressor increases the
pressure of the refrigerant
vapour causing it to
significantly increase in
temperature
Heat from the hot
pressurised refrigerant
vapour is transferred to the
water in the stored water
vessel by a second heat
exchanger called a
condenser.
As the refrigerant is cooled
it reverts back to its liquid
state.
The refrigerant liquid
passes through a pressure
reducing valve changing
from small bore to larger
bore pipe).
The reduction of pressure
significantly cools the
refrigerant fluid.
HEAT
EXCHANGER
Evaporator)
COMPRESSOR
1
2
3
STORED WATER
VESSEL CONDENSER
PRESSURE
REDUCING VALVE
EXPANSION VALVE)
4
To hot water taps
AMBIENT or
EXTERNAL
AIR
HIGH PRESSURE
REFRIGERANT IN
SEALED SYSTEM
Cold Feed

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1:8 TYPICAL INSTALLATIONS
Example 1.
NUOS installed in Utility Room.
Inlet air from room - not ducted.
Exhaust air ducted to outside.
Example 2.
NUOS installed in garage/outhouse.
Inlet air from internal duct.
Exhaustairductedtooutsidefromside
of unit.
Example 3.
NUOS installed in compartment.
Inlet air from outside.
Exhaustairductedtooutsidehighlevel
from top of unit.

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FIG. 1.9ANUOS COMPONENTS IDENTIFICATION
1.9 NUOS COMPONENTS IDENTIFICATION

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1.9 NUOS COMPONENTS IDENTIFICATION CONTINUED
The NUOS water heater essentially comprises an upper compartment
containing the heat pump assembly, a module which includes the control
panel and control circuit boards, and a storage vessel.
The storage vessel is internally coated with protective enamel treatment
and is externally insulated by a high efficiency polyurethane layer. The
storage vessel is enclosed within a powder coated steel casing.
Theheater element fitsinto the sideof the storagevessel. It iselectrically
poweredto heat the water to boost the heat pumpperformance orto heat
the water when the heat pump is off.
The air for the NUOS enters through a round vent at the rear of the unit.
Theaircouldbefromwithin the room orductedfromanotherroom,internal
space within the dwelling or more typically from outside.
Theexhaust air forthe appliance
can be directly into the room, or,
by using various ducting
arrangements, be ducted to
anotherroomor more typicallyto
outside the dwelling.
1.10 GENERAL LAYOUT
1.11 STORAGE VESSEL
1.12 HEATING ELEMENT
1.13 SUPPLY AIR
1.14 EXHAUST AIR
FIG. 1.14AAIR SUPPLY & EXHAUST
1. NUOSCylinder
2. Air Fan Outlet - Side
3. Air Fan Outlet - Top
4. Air Fan
5. AmbientAir Inlet
6. Evaporator
7. Compressor
8. Compressor Condenser
9. Thermostatic Expansion Valve
10. Pressure Safety Switch
11. Control Panel
12. Condensate Drain Pipe
13. DHW Temperature Sensor
14. Anode
15. Heat Exchanger (Condenser)
16. Electric Heating Element and Heating
Element Zone Sensors and Magnesium
Anode
17. Casing
18. HeightAdjustable Feet
19. Top Cover
20. Cylinder TPR Valve
21. Product Label
22. Manual Reset Overheat Stat (FSi 250 Only)
NUOS COMPONENTS IDENTIFICATION LIST
For further considerations for
supply and exhaust air refer to
sections 6.2 and 6.3.
Supply
Air
Side
Exhaust
Air
Top
Exhaust Air

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2. SAFETY
2.1 FLOOR MOUNTING The NUOS weights when full are:-
NUOS 200 - 290kg
NUOS 250i - 360kg
Thefloor on whichthe unit isto bestandingmust be capableofsupporting
(locally) the weight of the full unit.
Do not install the cylinder on floors made of chipboard or other flooring
where the mechanical strength is compromised when damp.
The NUOS should have 240V 10.8 amp electrical supply.
Allelectricalterminal coversmustbe screwed onbeforepower is switched
on.
The unit must be earthed.
The pipework to and from the unit must be earth bonded.
The unit must be protected by a 13 amp fuse.
The NUOS heat pump is classed as an unvented cylinder.
Itmustbe protected byapressure relief valve(PRV)andexpansionvessel
as detailed in section 6.9.
No valves must be fitted between the vessel and the PRV.
No valves must be fitted between the vessel and its expansion vessel.
When installing and servicing the appliance Ariston Thermo UK Ltd.
recommend the use of suitable protective clothing (i.e. gloves).
Itisrecommendedtouseasack barrow for liftingandmoving the packaged
NUOS.
Carrying the NUOS will require two fit persons.
Always follow the safe lifting guidelines as recommended by the Health
And Safety Executive www.hse.gov.uk.
IMPORTANT
The appliance should be kept in a vertical position when transported
or stored. During manual handling it can be carried at an angle (i.e.
in a sack barrow) or horizontally.
Ifhandlingentails moving the product inapositionotherthanvertical,
wait at least 3 hours before starting the appliance once it is in the
correct vertical position. This will ensure that the lubricating oil in
the refrigeration circuit is correctly placed in order to avoid the
compressor becoming damaged.
Refer to Section 5.2 Technical Data
2.2 ELECTRICAL
2.3 UNVENTED
2.4 PERSONAL PROTECTION
2.5 TRANSPORTATION
Also refer to page 2
2.6 REFRIGERANT

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HP
set
AUTO
3. USER INSTRUCTIONS IMPORTANT
This appliance is not intended for use by persons (including
children) with reduced physical, sensory or mental
capabilities, or lack of experience and knowledge, unless they
have been given supervision or instruction concerning use
of the appliance by a person responsible for their safety.
Children should be supervised to ensure that they do not
play with the appliance.
Once the NUOS unit has been fully commissioned, the
installer must give full guidance of use to the end user.
FIG. 3.1ACONTROL PANEL
3.1 CONTROL PANEL
ON/OFF Button
Press to turn NUOS ON.
Press again to turn OFF.
Mode Button
Press to select mode either Auto, Boost and Green, Voyage, P1,P2 or
P1+P2 (if enabled).
Also press to exit from installer and information menus.
Control Knob - User
Turn knob clockwise to increase to desired set temperature.
Turn knob anticlockwise to decrease to desired set temperature.
Press and release knob and the current temperature of the water within
the tank will be displayed for 5 seconds.
Control Knob - Information Menu
Press and hold the knob for 5 seconds to display Information Menu.
Turn knob clockwise / anticlockwise to scroll through information
parameters L0 to L14.
Press knob at selected parameter and it’s current value will be displayed.
Press knob again (or mode button) to return to Information menu.
ForInstallerMenuoperation refer
to 4.1.

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Set Temperature - 55°C
Min. Settable Temp. P2 50°C
Max Settable Temp.(with heat pump only) P3 55°C
Mode -Auto - On - Enabled
Mode - Boost - On - Enabled
Mode - Green P4 Off - Disabled
Mode - Voyage P6 Off - Disabled
Mode - Programs P1 & P2 P11 Off - Disabled
Programme P1 Temp. - 55°C
Programme P1 Time - 06:00hrs
Programme P2 Temp. - 55°C
Programme P2 Time - 18:00hrs
AntibacterialFunction P5 Off - Disabled
Defrost P7 On - Enabled
Time_W P9 8 hours
3.2 TURNING NUOS ON
3.3 DEFAULT SETTINGS
Display
Displays set temperature °C, mode, heat pump status and electric heater
status.
Smile Led
ON indicates NUOS is heating water.
Will also flash when system error is displayed, see 8.3.
To turn the NUOS ON and OFF, press the ON/OFF button.
The unit will turn ON in the same mode as when it was turned OFF i.e.
Auto, Boost, Green, Voyage, P1, P2 or P1+P2 (if enabled).
The NUOS has the following default settings on initial power up.
The desired temperature for the hot water is set using the ‘Control knob’ -
refer to 3.1.
The minimum temperature that can be achieved by the heat pump is
between 40°C and 50°C this limit is set by parameter P2.
Themaximumtemperature that canbeachieved by theheatpump without
using the heater element is between 50°C and 55°C this limit is set by
parameter P3.
The maximum temperature that can be achieved using the electric heater
is 65°C.
3.4 SETTING DESIRED
TEMPERATURE
HP
set
AUTO
HP
Heat Pump
active
Electric Heater
active
Set
Temperature
Mode - Auto, Boost, Green, Voyage P1, P2 or P1+P2
If enabled
Installers
Menu
parameter*
Parameter Default Setting
* See page 16

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The mode is set using the ‘Mode Button’ - refer to 3.1
Auto Mode
The NUOS operates giving priority to the heat pump to reach the set
temperature within a set time duration as determined by parameter P9
(default8 hours). If thecontrolcalculates thattheheat pumpalonecannot
achieve the set temperature within this time, then the heating element is
used as economically as possible to achieve the set temperature.
Boost Mode
TheNUOS operateswith bothheat pump and heating element to achieve
the set temperature in the shortest time. Once the set temperature is
reached the control switches toAuto mode.
Green Mode
The NUOS will operate using only the heat pump to achieve the set
temperature,withoutanytimedurationlimit. Thisensuresmaximumenergy
saving.
This function is recommended for air temperatures above 0°C during the
hours of heating.
Green mode is enabled/disabled by installer menu parameter P4.
Themaximumtemperaturethatcanbe achieved in greenmodeisbetween
50°C and 55°C this limit is set by parameter P3.
Voyage (holiday) Mode
Voyage mode is enabled/disabled by installer menu parameter P6.
Voyage modeenables the userto set anumber of daysthat the NUOSwill
not produce hot water.
The defrost will remain if enabled by P7.
The antibacterial function P5 will remain if enabled by P5.
To set holiday days:-
1. Press ‘mode’button until Voyage mode is displayed.
2. Turn control knob until the required number of days is displayed.
3. Press control knob to confirm.
The display will show the number of holiday days remaining.
When the set number of days have passed the NUOS will produce hot
water again inAuto mode. Therefore to return home and have hot water
available, set one day less than the days away.
Program Mode
Program mode is enabled/disabled by installer menu parameter P11.
There are three programme modes P1, P2 and P1+P2.
P1 Hot water will be available once per day
@ P1 set time @ P1 set temperature.
P2 Hot water will be available once per day
@ P2 set time @ P2 set temperature.
P1 + P2 Hot water will be available twice per day
First @ P1 set time @ P1 set temperature.
Second @ P2 set time @ P2 set temperature.
To set P1 and P2 times and temperatures:-
1. Press ‘mode’ button until P1 mode is displayed.
2. Turn control knob until the required temperature is displayed.
3. Press control knob to confirm.
4. Turn control knob again until the required time is displayed.
5. Press control knob to confirm.
Repeat above for P2.
3.5 SETTING OPERATING MODE
P1 and P2 are not switch on
times as normal water heating
systems.
The NUOS will start heating
water depending on the ambient
temperature to provide hot water
at the set times for P1 and P2.
The NUOS time setting must be
correct for P1 and P2 to operate
on time - see 3.8.
Notetheheating element will still
operate for defrost, antibacterial
functions and when air
temperature is out of operating
range.
Voyage Mode &ProgramMode:-
Intheevent of apowerfailure the
NUOS automatically switches to
Auto Mode.

14
3.6 USER SETTING PROCEDURES
3.7 SUMMARY OF NUOS OPERATION
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AUTO BOOST
set set
GREEN
set
VOYAGE
set
P1
set
P2
set
P1 + P2
set
set setset
Set Temperature
Set Mode
Set Voyage Days
* When enabled
AUTO
set
VOYAGE
set
VOYAGE VOYAGE
AUTO
set
P1
set
P1 P1 P1 P1
Set P1 °C & Time
(holiday)
Set P2 °C & Time
Also ‘P2’

15
15
3.8 INFORMATION MENU
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The Information Menu is displayed by pressing the control knob for 5
seconds.
The menu displays operating function status and monitoring information.
No changes can be made within the information menu (except current
time L0), any other settings that can be changed are changed in the
installers menu - see 4.1
Accessing Information Menu:-
1. Press control knob for 5 seconds.
2. Turn control knob until the required L number is displayed.
3. Press control knob to view current value / setting.
5 seconds
HC-HP T W 1
L0 to L14
HP
set
AUTO 47°C
Current Value
Access Information Menu
5 seconds
HP
set
AUTO
hh-mmhh-mm hh-mm
Setting Current Time L0
To set current time
1. Press control knob for 5 seconds until L0 hh:mm is displayed.
2. Press control knob again
3. Turn control knob to change current time.
4. Press control knob again.

16
4. INSTALLERS
SETTINGS
4.1 INSTALLERS MENU
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The Installers Menu is displayed by entering the correct code when P0 is
displayed in the information menu.
The menu enables the installer to set the NUOS operating parameters.
Accessing Information Menu:-
1. Press control knob for 5 seconds.
2. Turn control knob and go through L0 to L14 then the display will
show P0 code.
3. Press control knob again and the code 222 will be displayed.
4. Turn control knob to change the code to 234.
5. Presscontrolknob,theinstallersmenu P2 to P11willthenbeavailable
by turning control knob.
Installers Menu
5 seconds
HC-HP
HP
set
AUTO CO E
2 2 2 2 3 4
T Min
P2 to P11

17
17
5. TECHNICAL DATA
5.1 DIMENSIONS
FIG. 5.1ADIMENSIONS

18
Description FS 200 FSi 250
Tank Rated Capacity 200 litre 250 litre
Footprint (minimum) 0.6 x 0.6m 0.6 x 0.6m
Height 1.70m 1.96m
Weight Empty 90kg 110kg
Weight Full 290kg 360kg
Minimum ceiling height required 1.75m 2m
Maximum Operating Pressure 6 bar 6 bar
Condensate Drain ½” BSP F ½” BSP F
Air Intake Ø150mm Ø150mm
Air Exhaust Ø150mm Ø150mm
Maximum Duct Static Loss * 70Pa 70Pa
Cylinder - Tested in accordance with:- BS6700 EN 12897:2006
Normal Operating Pressure 3.5 bar 3.5 bar
Maximum Water Supply Pressure 12 bar 12 bar
Cold Connection (feed) ¾” BSP-22mm MI ¾” BSP-22mm MI
Hot Connection (draw off) ¾” BSP-22mm MI ¾” BSP-22mm MI
Pressure Reducing Valve Set Pressure 3.5 bar 3.5 bar
CylinderTPRV 90-95ºC / 7 bar 90-95ºC / 7bar
Combination Valve PRV 6 bar 6 bar
Expansion Vessel Pre-Charge Pressure 3.5 bar 3.5 bar
Cylinder Indirect Coil FSi 250 only
Connections ¾” BSP-22mm
SurfaceArea 0.65m²
Maximum Supply Pressure 6 bar
Rating @ 60°C 210.0 litres
Primary Flow Rate 15 l/min.
Pressure Drop through coil @15l/m 14 mbar
Heat Pump
Heat Rating** 2.775 kW 2.775 kW
Power Consumption** 0.75 kW 0.75 kW
COP** (see 1.7) 3.7 3.7
Heating Time** 3h:10min. 3h:40min.
Heating Energy Consumed** 2.2 kWh 2.7 kWh
Max. Water in Single Intake V40 @ 55°C 260 litres 325 litres
Max. Water in Single Intake V40 @ 62°C 348 litres 435 litres
Max. Water Temperature 55°C 55°C
Max. Current Consumption 3 amp 3 amp
Expansion Valve Operating Pressure 10-24 bar 10-24 bar
Refrigerant Fluid
Type of Fluid R134a R134a
Quantity 1.28 kg 1.28 kg
Practical Limit for Room Volume*** 5.12m³ 5.12m³
Max. Pressure of Circuit - low side 1.0 MPa 1.0 MPa
Max. Pressure of Condenser Coil 24 bar 24 bar
Max. Pressure of Circuit - high side 2.5 MPa 2.5 MPa
*Maximum permissible static loss for both supply air duct and exhaust air duct, when applicable.
**Values obtained with air temp. of 15°C and 37% relative humidity, input water temp. 15°C (in conformity to EN 255-3 specifications).
***The practical limit is the minimum room volume the appliance should be installed in, the volume is based on quantity of refrigerant in the
system. In the event of a sudden release of refrigerant then the minimum room volume will make it safer for the engineer.
5.2 TECHNICAL DATA

19
19
Description All models
Electric
ElectricSupply 220/240V, Single Phase, 50 Hz
Amp 10.8 amp
Connection 3 core flex supplied 1.2m long
Fuse Required 13 amp
Protection IPX4
Bathroom Zone Zone 2 - Switches/Fuse Zone 3
Electric Heater Rating kW1.5+1
Electric Heater Length 470mm
Electric Heater Type (1)
Electric Heater Max. Temp. 65°C
Air
Air Flow Rate 300 - 500 m³/h
Available Static Pressure 70 Pa
Sound Level @ 1m 56 dB(A)
Min. temp of room of installation 1°C
Max. temp of room of installation 35°C
Min. Volume of Room (non-ducted) 20 m³
Min.Air Temp Required (w.b.) @ 90% r.h. -5°C
Max. Air Temp Required (w.b.) @ 90% r.h. 35°C
Description FS 200 FSi 250
Reheat Time (▲T 45°C) mins
Heat Pump only (Green Mode) @ 100% capacity 236 mins 274 mins
Heat Pump only (Green Mode) @ 70% capacity 181 mins
Heat Pump & Heater (Boost Mode) @100% capacity 140 mins
Heat Pump & Heater (Boost Mode) @ 70% capacity 114 mins
Model time to raise 100% temp. from 15°C to 65°C 152 mins
Model time to raise 70% temp. from 15°C to 65°C 124 mins
Insulation
Heat Loss @ 65ºC 2.06 kW/24hr 2.05 kW/24hr
Ozone Depletion Potential (ODP) 0 0
Global Warming Potential (GWP) <5 <5
5.2 TECHNICAL DATA CONTINUED
5.3 KIT CONTENTS Direct kit for NUOS FS 200 pt. no. 3069418
Qty 1 Pressure Reducing Valve
Qty 1 Security Valve (6 bar)
Qty 1 Tundish
Qty 1 Expansion Vessel (18 litre)
Direct kit for NUOS FSi 250 pt. no. 3069419
Qty 1 Pressure Reducing Valve
Qty 1 Security Valve (6 bar)
Qty 1 Tundish
Qty 1 Expansion Vessel (18 litre)
Qty 1 2 Port Motorised Valve

20
5.5 REGULATIONS TheapplianceshouldbeinstalledinaccordancewiththeDomesticHeating
Compliance Guide and BS 3456.
These regulations (bye-laws in Scotland), ensure a good supply of
wholesome water and that only approved materials, pipes and fittings are
used to convey water.
Theseare a statutorydocumentand takepriority over allother regulations
and recommendations. The installation of an unvented hot water storage
cylinder is classified as a ‘Controlled Service’ and Regulation G3 applies.
To meet the requirements of the Regulation, installation of an unvented
system should be undertaken by a ‘competent installer’.
All installations of unvented hot water storage systems having a capacity
of more than 15 litres should be notified to the relevant LocalAuthority by
means of building notice or by the submission of full plans. It is important
to note that it is a criminal offence to install an unvented hot water storage
systemwithoutnotifyingtheLocalAuthority. Theinstallationoftheunvented
cylinder and hot water system must comply with BS 6700 and the HSE
Legionella Code of Practice.
Theappliance shouldbe installedinaccordance withthe currentversions
the IEE Wiring Regulations (now called BS7671 “Requirements for
electrical installations”)
5.6 WATER REGULATIONS
5.7 BUILDING REGULATIONS
SERIAL NUMBER
CAPACITY
WEIGHT WHEN FULL
VOLTAGE / FREQUENCY
MAXIMUM POWER CONSUMPTION
MAX PRESSURE HEAT PUMP
CIRCUIT HI/LOW PRESSRE SI E
MO EL
MAX. TANK PRESSURE
TYPE/QUANTITY OF REFRIGERANT
HEAT PUMP
POWER CONSUMPTION
HEAT PUMP HEAT RATING
TANK PROTECTION
IPX4
IP RATING
SYMBOLS
POWER CONSUMPTION ELECTRIC
HEATING ELEMEMENT
5.4 PRODUCT LABEL
FIG. 5.4APRODUCT LABEL
5.8 IEE WIRING REGULATIONS/
BRITISH STANDARDS