Potterton iHE 150 Release note

M6500
iHE
Indirect High Efficiency Boiler & Water Heater
Installation & Servicing Instructions
Models
iHE 100
iHE 150
This manual must be kept with the appliance

PERFORMANCE Unit 100 150
Category gas types II2H G20 @ 20 mbar
Qn Nominal Heat Input net (gross) kW 94.0 (102.2) 140.0 (152.1)
Qn Minimum Heat Input net (gross) kW 9.8 (11.1) 9.8 (11.1)
Pn Nominal Heat Output Max (50/30) kW 99.0 147.4
Pn Nominal Heat Output Min (50/30) kW 10.0 10.0
V Gas Consumption (G20) m3/h 9.9 14.8
Flue gas temperature max (min) oC 79 (50) 79 (50)
CO2 at max output (min output) % 9.3 (8.7) 9.3 (8.7)
CO at max output (min output) ppm 150 (3) 150 (3)
NOx emission at 0% 02 (dry) ppm (mg/kWh) 36.8 (56.7) 36.8 (56.7)
NOx Class 5 5
HEATING
Efficiency max heat output 50/30 net % 105.3 105.3
Efficiency min heat output 50/30 net % 102.5 102.5
Efficiency max heat output 80/60 net % 96.6 96.6
Efficiency min heat output 80/60 net % 95.2 95.2
Efficiency at 30% heat output net % 108.5 108.5
Seasonal efficiency gross % 95.6 95.6
PMS Operating pressure max (min) bar 3.0 (0.5) 3.0 (0.5)
Tmax Max permitted operating temperature oC82 82
Flow / Return connections BSP 2” 2”
Low Loss Header resistance kPa 0.5 0.5
HOT WATER
Tank capacity litres 300 300
Recovery rate through 50oC l/h 1520 2240
Time to recover tank through 50oC mins 12 9
PMS Operating pressure max (min) bar 6.0 (0.2) 6.0 (0.2)
In / Out connections BSP M 11/2”M1
1/2”
Water return connection BSP M 1” M 1”
ELECTRICAL
Electrical supply voltage / Hz V / Hz 230 / 50 230 / 50
Power consumption - standby A (W) 0.15 (34) 0.2 (40)
Power consumpion - maximum A (W) 3.3 (760) 3.82 (880)
Fuse rating on mains supply A 5 5
Insulation protection rating IP 20 20
FLUE
Flue connection - single mm 130 130
Flue connection - concentric mm 130 / 200 130 / 200
Max flue equivalent length - single m 30 30
Max flue equivalent length - concentric m 14 14
Flue systems permitted type B23, C13, C33 & C53
Approx flue gas volume @ 90oCm
3/h 160 242
OTHER CONNECTIONS
Gas BSP F 1” F 1”
Condensate mm 40 40
Immersion Heater BSP 2 1/4” 2 1/4”
Tank drain mm 28 28
WEIGHTS & CLEARANCES
Weight empty (full) kg 290 (608) 320 (641)
Service clearance - rear mm 0 0
Service clearance - right (with immersion) mm 300 (600) 300 (600)
Service clearance - top mm 350 350
Service clearance - left mm 800 800
GB, IE

iHE 1 GB/IE
TECHNICAL INFORMATION
Performance & measurement data Inside cover
1.0 GENERAL & SAFETY INFORMATION
1.1 Symbols used in this manual 2
1.2 Data plate & CE Marking 3
1.3 General warnings 4
1.4 Safety 4
1.5 Health 4
1.6 Description of appliance 5
1.7 General dimensions 6
2.0 INSTALLATION
2.1 Unpacking and location 7
2.2 New & existing heating systems 8
2.3 Water connections 9
2.4 Open vent design 9
2.5 Unvented design 10
2.6 Secondary return design 11
2.7 Condensate removal 11
2.8 Immersion Heater 12
2.9 Mixer Valve & actuator control 12
2.10 Flue systems & ventilation 13
2.11 Open flue type (B23)13
2.12 Room sealed type (Cxy)14
2.13 Flue terminal positions 15
2.14 Maximum flue lengths 16
2.15 Gas connections 17
2.16 Electrical connections 18
2.17 System schematic 19
2.18 Application drawings 20
2.19 Wiring diagrams 23
2.20 Wired room units & outside sensor 25
2.21 AGU2.5 Expansion modules 28
3.0 COMMISSIONING
3.1 Filling & starting the appliance 29
3.2 Running the circulation pumps 29
3.3 Commissioning the heat engines 30
3.4 Final checks & user handover 32
3.5 Frost protection & anti-legionella 32
3.6 Fault finding 33
4.0 SERVICE & MAINTENANCE
4.1 Recommended servicing 34
4.2 Changing components 35
4.3 Spare parts list 38
4.4 Appliance components identification 39
4.5 Fault codes list 42
CONTENTS

iHE 2 GB/IE
CORRECT USE OF APPLIANCE
This Potterton Commercial heating product has been designed and manufactured to comply with
current International standards of safety. However, following an improper use, dangers could
arise concerning the safety and life of the user or of other people, or damage could be caused to
the appliance or other object. The appliance is designed to be used in a pumped hot water central
heating system and potable hot water supply and storage. Any other use of this appliance will be
considered improper. Potterton Commercial declines any responsibility for any damage or injuries
caused by an improper use. In order to use the appliance according to its designed scope, it is es-
sential to carefully follow the instructions given in this guide.
DANGER!
INDICATES SERIOUS DANGER
TO PERSONAL SAFETY AND LIFE
WARNING!
INDICATES APOTENTALLY DANGER-
OUS SITUATION FOR THE APPLIANCE
AND THE ENVIRONMENT
NOTE!
SUGGESTIONS TO ASSIST THE USER
IN IMPLEMENTING INSTRUCTIONS IN
THIS GUIDE
1.1 SYMBOLS USED IN THIS GUIDE
SMELL OF GAS
If you smell gas - follow these safety instructions:
- Do NOT turn offor on any electrical switches (including light switches)
- Do NOT smoke
- Do NOT use the telephone
- DO evacuate persons away from the source of the gas smell
- DO close the main gas shutoffvalve
- DO open all the windows and doors where the gas leakage has occurred
- DO inform the gas authority or a competent specialist as soon as possible
OPERATOR COMPETENCY
This boiler is not intended for use by persons (including children) with reduced physical,
sensory or mental capabilities, or lack of experience and knowledge, unless they are given
supervision or instruction concerning the use of it by a person responsible for their safety.
Children should be supervised to ensure they do not play with the appliance.
BEWARE
The installation, adjustment & servicing of this appliance must be carried out by a competent
person (In the UK by a Gas Safe Registered Engineer and in IE by a (RGII) Registered Gas Installer)
and installed in accordance with current standards and regulations. Failure to correctly install or
maintain this appliance could cause injury to persons or damage to property. The manufacturer
shall not be held liable for any such injury and/or damage.
FLAMMABLE SUBSTANCES
Do not store or use explosive or easily inflammable material (such as petrol, paint or paper) in the
same room where the appliance has been installed.
Potterton Commercial’s policy is one of continuous improvement, and therefore the information
in this manual, whilst correct at the time of publication, may be subject to revision without prior
notice.
1.0 GENERAL & SAFETY INFORMATION

iHE 3 GB/IE
1.2 DATA PLATE & CE MARKING
There are two data plates located on the appliance . One is mounted on the inside of the electrical assembly
(which becomes visible when the left hand door is opened) and the other is on the outside casing just below
the electrical installation panel.
The CE marking documents that the appliance complies with the essential requirements of the following
directives:
- Gas appliance directive (2009/142/EC)
- Efficiency requirements directive (Council Directive 92/42/EEC) for condensing boilers
KEY
1 Type approval designation
2 Gas type and pressure
3 Model Name
4 Heat, gas flow & CO ² data
5 Technical data
6 Serial number
This manual is an integral and indispensable part of the appliance and it is suggested that this
manual is kept in a safe place for future reference.
1
1.
2
2
3
4
5
6

iHE 4 GB/IE
1.3 GENERAL WARNINGS
The appliance has been designed for use with G20 gas and is manufactured to give an efficient, reliable
and long service life.To ensure continued trouble-free operation of the appliance at maximum efficiency, it
is essential that correct installation, commissioning, operation and annual service procedures are carried out
strictly in accordance with the instructions given in this manual.
Only original parts and accessories from the manufacturer must be used on all appliances. Using non-approved
parts may compromise the safety of the appliance and invalidate any warranty.
The installation, commissioning and repair of this appliance must be carried out by a competent
person, in accordance with the manufacturers instructions and complying with the National Laws in
force at the time. (In the UK a competent person must be a Gas Safe registered Engineer or in IE by a
Registered Gas Installer (RGII)).
In the event of failure and/or suspected faulty functioning of the appliance. Switch offthe appliance and con-
tact suitable qualified technicians. Do not attempt to make any repairs unless you are suitably qualified and
competent to do so.
1.4 SAFETY
This appliance must be installed in accordance with local building regulations, national standards and bye laws
in force. Attention should be given to the following standards and guidance notes:
GAS SAFETY (INSTALLATION AND USE) REGULATIONS
BUILDING REGULATIONS
THE WATER SUPPLY (WATER FITTINGS) REGULATIONS
Detailed recommendations are contained in the following codes of practice:
BS 6880: Low temperature hot water heating systems of output greater than 45kW.
Part 1 Fundamental Design
Part 2 Selection of equipment
Part 3 Installation, commissioning and maintenance
BS 6644: Specification for installation of gas-fired hot water boilers of rated inputs of between 70kW (net)
and 1.8MW (net) (2nd & 3rd family gases)
BS EN 12897 Specification for indirectly heated unvented (closed) storage water heaters.
The following could be relevant dependent upon the installation:
IGE/UP/1 - 1A -1B Strength & tightness testing of industrial and commercial gas installations.
IGEM/UP/2 Gas installation pipework, boosters and compressors on industrial and commercial premises.
IGEM/UP/4 Commissioning of gas fired plant on industrial and commercial premises.
IGE/UP/7 Gas installations in timber frame buildings.
IGE/UP/10 Gas Installations in industrial and commercial premises.
IEE Wiring Regulations for electrical installations (BS7671)
NOTE: Consideration should be given to amendments or updates to the above standards.
1.5 HEALTH
It is the duty of manufacturers and suppliers of products to ensure, so far as is practicable, that such products
are safe and without risk to health when properly used and to make available to users, adequate information
about their safe and proper operation.
This appliance should only be used in the manner and purpose for which it was intended and in accordance
with the instructions in this manual. Although the boiler has been manufactured with paramount considera-
tion to safety, certain basic precautions specified in this manual must be taken by the user. It is imperative
that all users of it must be provided with all the information and instruction necessary to ensure correct and
safe operation.

iHE 5 GB/IE
COMBATTING LEGIONELLA
Water systems in buildings have been associated with outbreaks of Legionnaires’ Disease, particularly in health
care facilities where occupants are significantly more susceptible to infection. In recognition of the risks in hos-
pitals, a Code of Practice for the Control of Legionella in Health Care premises has been issued by the Depart-
ment of Health.
Codes of Practice applicable to other premises have been published by other organisations, principally the
Health and Safety Executive (HS) (G70) and the Chartered Institute of Building Services Engineers (CIBSE,
TM13). All Codes of Practice draw attention to the design and operation of water systems with reference
to avoidance of factors that favour colonisation by Legionella bacteria. These factors include stagnation,
lukewarm conditions (20ºC to 45ºC) and the accumulation of debris, scale and corrosion in the base of tanks and
calorifiers.
An independent evaluation of our products was commissioned to investigate their resistance to the build-up of
Legionella bacteria. Experiments were conducted to determine whether, following a substantial challenge by
Legionella Pneumophilia, after overnight and stagnation conditions, the system was rendered free from viable
recoverable Legionella. It was found that at 61ºC, following a challenge of approximately 107 organisms per
litre, within one hour, more than 99.999% of organisms had been killed. After a subsequent stagnation period,
sampling did not reveal any residual contamination. The design of the base of the integral water tank precludes
Legionella colonisation, even after build-up of debris. The heating process ensures that the water at the bottom
of the tank reaches the same temperature as in the rest. In addition the controls of the appliance provide anti-
legionella routines to provide additional protection.
Based on data obtained through experiment, this appliance can be described as Legionella resistant as it is
considered unlikely that, at the temperature tested, the organism would colonise the water heater and present
a possible health risk.
1.6 DESCRIPTION OF APPLIANCE
The Potterton iHE is a gas fired, low No×, multi-heat engine cascading boiler system, with an integrated 5” Low
Loss Header for the supply of a low temperature hot water space heating system. The Sirius Advance range of
boilers also features an integrated stainless steel tank and plate heat exchanger for the supply of hot water.
Fully automatic electronic controls are integrated into the appliance, with a wide range of control and sensor
options available. The controls also provides voltage free outputs for Enable, Burner On, Fault and 0-10V input
for remote BMS use.
Each heat engine module consists of a stainless steel combustion chamber, premix burner, modulating fan, gas
valve, ignition and flame detection electrodes and a NTC flue sensor for safety supervision.
Each heat engine module is equipped with NTC sensors for precise temperature control on flow and return mani-
folds. Fully premixed, radiating, modulating burner, integrated with gas valve to deliver precise gas/air mixture
throughout the full modulation range.
Common combustion air intake manifold, takes air from boiler room (type B23 flue) or directly from outside via
a combined flue system (C13 & C33). An air control non-return flap is integrated into the air supply of each heat
engine, to ensure that flue products cannot contaminate the air supply, when the heat engine is not in use.
The safety and operation functions of each heat engine are managed by micro processor controlled circuit
boards, one for each heat engine. The upper controller also acts as the cascade controller, switching/modulat-
ing the heat engines according to the demand and data from the systems sensors. Control is performed using
comparison parameters between the requested temperature and the global flow temperature.
CONTROL LOGIC:
At full demand, each heat engine is ignited one at a time, until all heat engines are operating at full output. As
flow and return temperatures increase, all heat engines will begin to modulate down together, until all are oper-
ating at minimum input rate. As flow temperatures begin to approach the calculated set point, one of the heat
engines will stop, leaving the others operating at minimum input rate. This will continue until all heat engines
have stopped and temperature flow requirements have been fully satisfied.

iHE 6 GB/IE
Fig 1.1
78
1450
678
515
46
105
812
1033
1708
253
84
540
1970
1987-REMOVEABLEAIRDUCTSPIGOTFORINSTALLATION
127
Safety Valve & Tundish 3/4" BSP F
Condensate Trap 41mm
Low Loss Header Return 2" BSP F
Low Loss Header Flow 2" BSP F
Gas Inlet 1" BSP F
Wiring Centre Door
Front LH Door
Front
RH Door
RH Side
Upper LH Side
Lower LH Side
Top
Multiple Cable
entry point
1941
192
104
Low Loss Header Air vent
User Display
43
268
190
179
149
191
238
Cylinder Hot Water Supply 1.5" BSP M
Cylinder Return 1" BSP M
Air/Flue Duct
200mm/130mm
Pressure Gauge
Fill/Drain 15mm
497
132
Cylinder Drain 28mm
701
302
Immersion Heater Boss 2.25" BSP F
1871
80
PT Valve exits
100kW - 1 x 28mm
150kW - 1 x 28mm & 1 x 22mm
1.7 GENERAL DIMENSIONS
Minimim Service Clearances (mm)
Rear 0 Right (without immersion) Right (with immersion)
300 600
Left 600 Top 350

iHE 7 GB/IE
The appliance is delivered assembled and
protected by a plastic bag, inside a strong
wooden crate. The packaging is designed
to be handled by a forklift or pallet truck.
The complete crated appliance can go
through a door of 2,320mm high. Without
packaging it can go through a door
1,970mm high.
Remove nails fixing crate sides to the base. Remove
nails from one end of the crate. Remove end of crate
and slide the main body of the crate offthe oppo-
site end.
Remove plastic wrapping once the appliance has
reached its intended installation area.
Dispose of plastic packaging carefully.
Keep out of the reach of children and
animals.
LOCATION
The location selected for installation of the appli-
ance must allow the provision of a satisfactory flue,
an adequate air supply (for type B23), a drain and
be well illuminated. A purpose built plant room or
compartment is strongly recommended.
If a purpose built plant room is not available, meas-
ures should be taken to protect the appliance from
damage and prevent any extraneous matter from
being stored on or around the Heater. See BS 6644
Clauses 4, 5 and 6 for details. Any combustible ma-
terial adjacent to the appliance must be so placed
and shielded as to ensure that it’s temperature does
not exceed 66ºC (150ºF).
There must be easy access to the plant room and
boiler at all times. The appliance must be located in
an area where leakage from the tank, water con-
nections or the combined temperature and pres-
sure safety valve will not result in damage to the
area adjacent to it. When such locations cannot
be avoided, a suitable drain tray must be installed
under the Heater. The drain tray must be no deeper
than 38mm and must be 100mm wider and longer
than the boiler. It should be piped to an adequate
drain using 20mm (0.75in) diameter pipe, angled for
proper drainage.
Access must be provided to the front of the boiler
with adequate clearance for servicing and opera-
tion. (Fig 1.1)
The floor on which the boiler is installed must be
flat, level and of sufficient strength to withstand
the weight of it when filled with water, and should
satisfy the requirements of the Local Authority &
Building Regulations.
Whether connecting to an existing or a new
heating system, a filter/strainer (with two
isolation valves) must be fitted in the return
pipe. When necessary it can be removed
and cleaned, which will help protect the
appliance from contaminants, from within
the heating system.
APPLIANCE FLOOR FIXING KIT
This appliance has been supplied with plates to fas-
ten the appliance securely to the floor.
There are four floor fixing plates (M6644) included
with this unit. Two have been packed separately with
the Air Duct kit that includes these instructions and
another two plates have been used to fasten the
appliance to the pallet.
Central Floor fixing method (two plates required)
Once the appliance has been located on a level sur-
face, fix the appliance to the floor using the follow-
ing method.
1) Slide plate into position so that it interlocks onto
the LH central base support . Mark floor
with hole position and remove plate (Fig 2.1).
2) Drill marked position on floor to allow installers
preferred method of fixing.
3) Refit plate and fasten through using preferred
fixing method.
4) Repeat method at the RH end of the central
base support.
Fig 2.1
2.0 INSTALLATION
2.1 UNPACKING AND APPLIANCE LOCATION

iHE 8 GB/IE
Central Floor fixing method (four plates required)
If the central fixing positions are unsuitable for the
installation, alternative positions can be utilised in
the corners. (Fig 2.2) This method can only be used
if the installer has kept the pallet fixing plates and
has four plates in total.
Follow points 1 - 4 above for fixing instructions.
2.2 NEW AND EXISTING HEATING
SYSTEMS
EXISTING SYSTEMS
Before replacement of an existing boiler, it
is necessary to thoroughly clean out the
old system first. This is best achieved intro
ducing a basic cleaning solution 4 weeks
before the substitution.
When the appliance is installed on existing systems,
please ensure you have considered the following
before commissioning:
- If you intend to use the existing flue on a B23
category system, check that flue outlet is suitable
for condensing boilers, is the correct size, is correct
for the temperature of the products of combustion
and is manufactured according to current
regulations. It must be tested for soundness and
must not have any restrictions or defects. Also
ensure that the flue outlet pipe has a connection for
the discharge of condensate. For all other flue
types, it is recommended that a completely new
flue system is installed.
- The boiler room has a suitable outlet for the
discharge of condensate produced.
- The electrical connections comply with the current
electrical standards and the work has been carried
out by a suitably qualified person.
- The gas supply pipework is constructed to the
current regulations in force.
-The expansion vessels and associated fittings are
correctly sized to absorb the total expansion of the
system and in tested working order.
- The circulation pump’ s output, the head and flow
direction are suitable.
- The complete system has been cleaned of
impurities and lime scale.
NEW SYSTEMS
It is recommended to thoroughly clean out the new
system with a system flush product, before commis-
sioning the appliance.
SYSTEM INHIBITORS & PH LEVELS
After cleaning and flushing of the system, it should
be filled with an appropriate inhibitor/antifreeze
treatment to maintain pH levels of between 7.5 &
9.5pH.
The following system treatments have been tested
and are recommended for use in this appliance:
FERNOX SENTINEL
Inhibitors Protector/
Alphi 11
X100, X500
Noise reducer X200
Universal cleaner Restorer X300
Sludge remover Protector,
Restorer
X400
Antifreeze Alphi 11 X500
Fig 2.2

iHE 9 GB/IE
2.3 WATER CONNECTIONS
GENERAL
The cold water inlet and hot water outlet connection
nipples are identified on top of the appliance.
Connect the cold water feed and hot water outlet
to these nipples with union adaptors for ease of
servicing. Connect the supplied isolating valve to
the drain connection and pipe to a suitable discharge
point.
(See fig 1.1 for connection locations)
Do not apply excessive torque to these
nipples when making connections. The
use of an appropriate pipe sealing
compound s recommended
COLD WATER SUPPLY - SYSTEM
The appliance may be connected to an open vent or
sealed system supply. When connected to a sealed
system an unvented water kit must be installed with
a minimum water pressure of one bar. The appliances
are factory fitted with temperature and pressure
relief valves. An unvented system must be fitted by
an approved installer.
Cold Water Supply - Quality and Treatment
In hard water areas scale formation can occur in all
hot water systems and the higher the volume and
hotter the water used, the greater and more prob-
lematic the scale build-up can be. Water treatment
is usually recommended when the hardness levels
measures greater than 150 ppm. For this reason,
base exchange water treatment is strongly recom-
mended in hard water areas.
2.4 OPEN VENT DESIGN
The tank must be supplied from a cold water feed
cistern and the hot water supply pipe must be fitted
with an open vent pipe in accordance with BS 5546
and BS 6644. The Water Supply (Water Fittings)
Regulations must be observed when installing the
system.
The cold water feed cistern must have an actual
capacity greater than the hourly recovery rate of the
heater or heaters to which it is fitted, the minimum
actual capacity allowed for a feed cistern being 227
litres (50 gallons).
The actual cistern capacity is the capacity to the
normal water level of the cistern. All cisterns should
be manufactured to the relevant Standard.
The distance from the normal water level to the top
of the cistern should comply with that specified by
the Water Authorities.
SECONDARY RETURN (FIG 2.5)
A Secondary Return circuit may be fitted to the 1”
nipple at the top of the appliance. In all cases, for
serviceability, the recirculation pipe must be fitted
with a stop valve immediately before the connec-
tion point.
DE-STRATIFICATION
By virtue of its design an internal DHW tank de-
stratification pump is not required.
T&P Valve Outlets
Minimum 2.0m
2 x T&P Valves
Service Valve
Cold In
Hot Out
Service Valve
Drain
Pump Outlets
Return
Fig 2.3
iHE OPEN VENT EXAMPLE

iHE 10 GB/IE
2.5 UNVENTED DESIGN
Unvented Systems should only be
fitted by an Approved Installer
When using the Heater on an unvented hot water
storage system, the Unvented System Kit, part
number B328, available from the manufacturer
must be fitted. See section 4.4
When used in an unvented system, the Heater will
supply hot water at a maximum of 3.5 bar or at the
pressure available at the mains feed if this is lower.
During conditions of no-flow, system pressure may
rise to a maximum of 6 bar, whilst the burner is
operating. When testing the system, it is recom-
mended that a maximum test pressure of 7 bar is
used.
For the hot water supply, a 25 litre expansion
vessel is suitable for the stored volume of all mod-
els of the Heater and an average pipework system.
For systems with larger pipe volumes or additional
storage, expansion vessels with greater capacity
are availaible.
Assemble the components of the unvented system
kit as shown in Fig 2.4
For the Central Heating supply the expansion ve-
sel must comply with BS4814 and must be sized on
the basis of total system volume and initial charge
pressure. Initial minimum charge should not be less
than 0.5 bar and must take into account static head
and specification of any pressurising equipment.
When assembling the Pressure Reducing
Valve and Double Non-Return Valve,
ensure that the flow arrows marked on the
components are pointing in the direction of
flow, that is towards the Heater.
The relief valves fitted to this appliance must not
be used for any other purpose. No fitting should
be installed between the expansion valve and the
cylinder.
The cold water for services may be drawn from the
22mm compression port up strea of the Pressure
Reducing Valve. The water pressure at this point
will be similar to that available at the hot water
outlet of the water heater.
If higher flow rates are required for the cold water
services, a suitable tee fitting should be fitted to
the pipework, upstream of the Pressure Reducing
Valve.
The pipework fitted to the tundish outlet should be
at least 28mm diameter, made of metal and should
be terminated at a suitable drain (see Building
Regulations Approved Document G3).
All fittings and materials supplying water to the
storage vessel must be suitable for use with drink-
ing water and listed in the current Water Research
Centre “Materials and Fittings Directory”.
Installation of unvented hot storage water systems
must comply with Part G of Schedule 1 of the Build-
ing Regulations.
Fig 2.4
Expansion
Vessel
WallBracket
Assembly
Hose Assembly
Cold Water Inlet of Water
Cold Water Feed
Tundish
Check Valve
Expansion Valve Pressure Reducing
Valve/Strainer
Balanced Cold Water
Take-off (if required)
Temperature &
Pressure Relief
Valve
Hot
Water

iHE 11 GB/IE
CONDENSATE DISPOSAL EXAMPLES
Gully
There is no requirement for an additional trap
if discharging direct into an open gully.
Soil / Vent Stack
There is no requirement for an additional trap or air
break when connecting drain pipework to an internal or
external soil or vent stack
MIN 110mm FROM A BRANCH PIPE
110MM SOIL / DRAIN STACK
Fig 2.6
2.7 CONDENSATE DISPOSAL
Condensation is formed in the normal operation
of the appliance and this must be continuously
discharged into a drain. Given the acidity level of
condense discharge (pH 3.5 - 4.5) only plastic mate-
rial can be used for the discharge pipe work.
40mm pipe with a drop of at least 30 mm for every
metre of pipework should be used. A trap is sup-
plied which should be connected into a drain via a
tundish or air break.
External pipework and that passing through a wall
to the outside should be run in a minimum of 40mm
Fig 2.5
diameter. External pipework should be insulated to
protect against frost and freezing temperatures.
The condensate trap must be filled with
water before operating the appliance.
It is important that the condensate flow
must be maintained, even in freezing
conditions. In the event that the condensate
becomes blocked, the appliance will
shutdown completely, and will not operate
again until the flow has been restored.
2.6 SECONDARY RETURN DESIGN

iHE 12 GB/IE
2.8 IMMERSION HEATER
An immersion heater boss is fitted in the side of
the DHW tank in order to facilitate the fitting of an
electric immersion heater.
This immersion heater must have a 2 1/4” BSP male
thread and a nominal length of no greater than
400mm
Max
400mm
Fitting
Switch off the DHW circuit and with the tank drained
of water, remove the threaded bung
Place a suitable supplied gasket around the heater
base. Keeping the heater element horizontal and
square with the boss, insert the heater into the
opening. Secure by turning the heater onto the
threads.
Once heater is firmly screwed into boss, fill the tank
with water and check for leaks at maximum opera-
tional pressure.
Install electrical supply to immersion heater accord-
ing to the manufacturers instructions, ensuring that
the heater is wired with heat resisting or mineral
insulated cables complying with BS6207.
INTEGRATION WITH CONTROLS
The appliance controls have the facility to activate
an immersion heater as a backup for the normal
generation of DHW. e.g. The immersion heater
would be automatically switched on if the appliance
was unable to generate DHW for any reason
Refer to Fig 4.6 on page 22 for suggested details
on how to wire an integrated immersion heater.
The optional purchased AGU2.5 “module” (# 3) would
require to be defined under parameter 6022 as “Multi-
functional”. The output QX23 and other settings would
be defined according to the following table:
Menu Line
no
Setting
Config (QX23) 6038 El imm heater DHW K6
To configure as a backup heater
DHW storage
tank
5060
5061
5062
Substitute
Time program 4 / DHW
External thermostat
To configure as a summer heater
DHW storage
tank
5060
5061
5062
Summer
Time program 4 / DHW
External thermostat
To configure as an independantly controlled
heater
DHW storage
tank
5060
5061
5062
Always
Time program 4 / DHW
External thermostat
2.9 MIXING VALVE & ACTUATOR
CONTROL
The AGU2.5 “Module” can be used to control a 230V
valve actuator to regulate the flow temperature
of the heating circuit to which it is connected. The
actuator uses 3-point control to open and close the
valve.
Refer to Fig 4.4 on page 20 for suggested details
on how to wire a mixing valve
In this example, if the temperature of HC1 needed
to be increased, the controls would supply 230V
through QX21 (Y1) to open the valve until the tem-
perature rise was detected by the sensor B1.
If the temperature of HC1 needed to be decreased
the controls would supply 230V through QX22 (Y2)
to close the valve until the temperature fall was
detected by sensor B1.
Precise temperature control is maintained by al-
ternating 230V via QX21 & QX22 until the desired
temperature is maintained, at which point no voltage
maintains the valve position.

iHE 13 GB/IE
VENTILATION REQUIREMENTS FOR TYPE B(OPEN FLUE
SYSTEMS)
Refer to BS 6644 clause 19 and BS 5440 part 2 for
detailed recommendations.
The room in which an appliance is installed must
have a permanent air vent to outside air or to a
room which itself has direct access to outside air.
Installations in boiler rooms require permanent
vents for air supply purposes, one at high level and
one at low level, direct to outside air. The minimum
free areas required are as follows:-
Low level (inlet) iHE 100 = 376 cm2
iHE 150 = 560 cm2
High level (outlet) iHE 100 = 188 cm2
iHE 150 = 280 cm2
Where the appliance is to installed in a compart-
ment, permanent air vents are required at high and
low level. These air vents must either connected
with a room or internal space, or be direct to out-
side air. The minimum free air requirements in the
compartment are as follows:-
Position of
air vents
Air from room or inter-
nal space
Air direct from
outside
High Level iHE100 = 940 cm ²
iHE150 = 1,400 cm2
iHE100 = 470 cm2
iHE150 = 700 cm2
Low Level iHE100 = 1,880 cm ²
iHE150 = 2,800 cm2
iHE100 = 940 cm2
iHE150 = 1,400 cm2
A compartment containing an open-flued appliance
shall be labelled as follows:
IMPORTANT: Do not block the vents. Do not use
the compartment for storage.
Where an installation is to operate in summer
months, the above allowance should be sufficient,
provided it does not operate for more than 50%
of the time. If the installation is to be operated at
75% then an additional 1cm2will be required per
kW at low and high level. If this appliance is to be
operated 100% of the time during the summer, an
additional 2cm2free-area per kW will be required at
low and high level.
There must be sufficient clearance around
the appliance to allow proper circulation of
ventilation air. The clearances required for
Installation and Servicing will normally be
adequate. (See Fig. 1.1)
The effect of any type of extract fan in the
plant room must be considered and an
additional air inlet may be needed from
outside to counter the effect of any such
fans.
2.10 FLUE SYSTEM & VENTILATION
In order to minimise the height of this appliance, the
flue spigot plate assembly is supplied separately
and will have to be installed before fitting the flue
system:
• Fully insert (approx 50mm) plastic flue pipe sec-
tion (supplied) into flue socket (fig 3.1).
Fig 3.1
• Screw metal air colar onto the top of the flue
socket with the 8 screws (supplied) (fig 3.2)
Fig 3.2
The appliance can be installed using a number of al-
ternative arrangements depending upon the installa-
tion requirements It is delivered with a 130/200mm
concentric outlet in the centre. Flue components are
ordered separately as required.
2.11 OPEN FLUE (TYPE B23)
This is an open flued arrangement where the air for
combustion is drawn from the room and because of
this the room must be ventilated. If the Heater is
installed in a compartment then it will require both a
high level and a low level vent.
The flue products are discharged either horizontally
or vertically using any of the supplied separate duct
components.

iHE 14 GB/IE
Fig 3.3
C13 AND C33 FLUE TERMINAL ARRANGEMENTS
Clips every
1000 mm
2.12 ROOM SEALED FLUE (TYPE CXY )
There are three approved room sealed arrangements where both the air inlet and flue discharge terminate
outside the building.
TYPE C13 & C33 FLUE AND AIR DUCTS TERMINATE EITHER HORIZONTALLY OR VERTICALLY IN THE SAME POSITION
Flue and air ducts are supplied to a concentric design (130/200mm). See Fig 3.5 for component choices.
Flues should slope back to the Heater by 3 degrees.
Terminal positions must comply with the requirements detailed in section 2.12
VENTILATION REQUIREMENTS (TYPE C13, C33 & C53 )
Where the appliance is installed in a ROOM or COMPARTMENT no additional ventilation is required.

iHE 15 GB/IE
Minimum Distance mm
A Directly below an opening, air brick, opening window etc. 300
B Above an opening, air brick, opening window etc. 300
C Horizontally to an opening, air brick, opening window etc. 300
D Below a gutter or sanitary pipework 75
E Below the eaves 200
F Below a balcony or carport roof 200
G From vertical drain or soil pipework 150
H From an internal or external corner 300
I Above ground, roof or balcony level 300
J From a surface or a boundary line facing a terminal 600
K From a terminal facing a terminal (Horizontal flue) 1200
K From a terminal facing a terminal (Vertical flue) 600
L From a opening in a carport (e.g. door, windows) into the building 1200
M Vertically from a terminal on the same wall 1500
N Horizontally from a terminal on the same wall 300
R From an adjacent wall to flue (Vertical only) 300
S From an adjacent opening window (vertical only) 1000
T Adjacent to windows or openings on pitched and flat roofs 600
U Below windows or opening on pitched roofs 2000
The flue discharge position for any flue type must conform to the following requirements
2.13 FLUE TERMINAL POSITIONS
Likely flue positions requiring a flue guard terminal
Fig 3.3

iHE 16 GB/IE
Concentric Flue C13, C33 & C53
Item F.E.L.
1m length 1.0
45° bend 0.5
90° bend 1.0
Horizontal Terminal 1.0
Vertical Terminal 1.6
Flue Parts Part Number
1.0 m Concentric Length E212
0.5m Concentric Length E214
Concentric 90° Bend E215
Concentric 45° Bend E216
Flue Condense Trap E220
Horizontal Terminal kit E240
Terminal Guard E630
Vertical Terminal kit E670
Wall Clamp 200mm E219
2.14 MAXIMUM FLUE LENGTHS
The combustion fan fitted to the appliance moves
the air and flue products through the system and
can provide sufficient capacity for a Flue Equivalent
Length (FEL) of 18 metres for type C13 and C33
systems and 30 metres for type B23 system.
Each flue accessory such as bends and straight
lengths restrict the flue system and have a FEL
which must be added together to determine the
total.
Referring to the table below, select a suitable flue
system for the particular installation requirement
and then calculate the FEL of the system, this must
not be greater than that stated above.
Examples:
Concentric Flue Type C13
A flue system that uses ten straight lengths, three
90° bends, two 45obends and a horizontal terminal.
10 x 1m straight length 10.0
3 x 90° bends 3.0
2 x 45obends 1.0
1 x Horizontal Terminal 1.0
Total (within 18m limit) 15.0
Concentric Flue Type C33
A system that rises from the Heater and uses seven
straight lengths, four 45° bends and a vertical
terminal.
7 x 1m straight lengths 7.0
4 x 45° bends 2.0
Vertical Terminal 1.6
Total (within 18m limit) 10.6
Open Flue Type B23
The maximum FEL of flue in this configuration is 30
metres.
The air inlet connection to the appliance must
be fitted with a Debris Guard. Air is drawn from
the room or compartment in which the heater is
installed and therefore the room or compartment
must be ventilated. See Page 11.
The flue duct can discharge either vertically or hori-
zontally by selection of the correct flue terminal.
The flue pipe can be fitted with 90 and 45 degree
bends as well as extensions.
Fig 3.4

iHE 17 GB/IE
2.15 GAS CONNECTIONS
GAS SUPPLY
A manual valve for isolation of the gas supply to
the appliance should be installed nearby and it
should be clearly identified and readily accessible
for use at all times.
The installation of the gas supply must conform, to
the British Standards and Codes of Practice listed in
Section 1 of this manual.
The appliance should be fitted with a gas isolating
cock, a supply pipe of 1” Steel pipework and can be
supplied from any direction.
The gas supply pipework must be fitted with suit-
able unions so the Heater can be safely removed
for major service or repair.
NATURAL GAS
The gas meter, regulator and supply pipework must
be sized so as to provide an adequate supply to
the appliance in addition to any other appliances
connected to the supply. (See Technical Data on
the inside cover for Pressure and Flow Rate require-
ments.)
Where this appliance is installed in a plant room or
purpose built compartment, a manually operated
valve must be fitted in accordance with the Gas
Safety (Installation and Use) Regulations. The valve
must be easily identified and readily accessible.
GAS CONNECTION
The 1” galvanised steel gas connection is provided at
the top of the appliance. A minimum of 20mb (G20)
running pressure, must be available at the appliance
inlet, with this appliance and other connected appli-
ances operating
This will require a test point on the
supply to the appliance, the gas valve inlet
pressure tapping should not be used,
whilst the appliance is being operated, as
this may give an incorrect reading.
Check for gas tightness (BS. 6891) in pipework to the
appliance by connecting a manometer to the inlet pres-
sure tapping point.(See Fig. 4.1) Gas and combustion
soundness within the appliance should be checked us-
ing sense of smell and leak detection fluid. Ensure gas
tightness before moving onto to commissioning.
Inlet pressure tapping
measurement point
Fig. 4.1

iHE 18 GB/IE
2.16 ELECTRICAL CONNECTIONS
This appliance must be earthed
Isolate the mains electrical supply before
starting any work and observe all relevant
safety precautions
External wiring to the appliance must be installed
in accordance with current I.E.E. Regulations for the
wiring of buildings and to any Local Regulations
that may apply.
The appliance is designed to operate from a 230V,
single phase supply fused at 5 amps. Mains input
cable should be at least 0.75mm2, 3 core cable.
The method of connection to the mains electricity
supply should facilitate complete electrical isola-
tion of the appliance. A fused double pole switch
or fused spur box serving only the heater may be
used.
The point of connection to the mains electricity
supply should be readily accessible and adjacent
to the appliance, and should be connected to the
mains supply as detailed above.
ACCESS TO THE TERMINAL CONNECTIONS
Remove the Side Access Panel (See Fig 1.1) to expose
the electrical connections.
A permanent live supply must be connected to the
appliance. Automatic timed or remote operation of the
appliance can be achieved by connecting to the volt
free “Remote Enable” terminals after removing the
link wire. (Fig. 4.2)
REMOTE INDICATORS:
The appliance has a volt free (or can be used with
voltages up to 230v) output, which can be connected
to a Building Management System or a remote indica-
tor panel. This input is connected to the AGU2.5 #2 “L”
terminal.
FAULT
Five minutes after any fault occurs within the appli-
ance an internal relay will activate and connect AGU2.5
#2 “L” to AGU2.5 #2 “QX22”
BURNER ON
When the appliances heat engine/s are in operation an
internal relay will activate and connect AGU2.5 #2 “L”
to AGU2.5 #2 “QX21”
Fig 4.2
LBr
1
G+ Or
19
NB
2
CL- Bk
20
EG/Y
3
CL+ R
21
R
4
W
22
B
5
W
23
G/Y
6
Y
24
Or
7
Y
25
Gy
8
SPARE
26
B
9
Gy
27
G/Y
10
Gy
28
R/B
11
G
29
B
12
G
30
G/Y
13
P
31
1
14
Bk/Gy
32
2
15
B/Gy
33
3
16
Bk
34
4
17
Bk
35
5
18 36
AGU2.5 #1
H2
M
QX21 (RUN)
BMS/REMOTE
SYSTEM ENABLE
H5
AGU2.5 #1AGU2.5 #2
H2
M
M
Low Voltage230 Volts
QX23
N
AGU2.5 #3
SPARE
L (COMMON)
Link if not
used
QX22 (FAULT)
HC ROOM
CONTROL
UNIT RC
(QAA55/75)
OUTDOOR
SENSOR B9
(QAC34)
N
E
BX21QX23
E
AGU2.5 #3
230V 50Hz
5A
MAINS
SUPPLY
IN
AGU2.5 #1
QX21
QX22
N
E
ELECTRICAL CONNECTIONS