ideal Istor HE 260 User guide

installation and
servicing

istor

(V3 Flue System)

Your Ideal installation and servicing guide

For details of document amendments, refer to page 3

When replacing any part on this appliance, use only spare parts that you can be
assured conform to the safety and performance specification that we require. Do not
use reconditioned or copy parts that have not been clearly authorised by Ideal Boilers.

HE260, HE325

For the very latest copy of literature for specification purposes please visit our website
www.idealboilers.com where you will be able to download the relevant information in pdf format.

PACKAGED BOILER CONTENTS

HAVE BEEN CHECKED BY OPERATOR No........

January 2010 UIN 203325 A04

2

istor system store - Installation and Servicing

DOCUMENT AMENDMENTS

Relevant Installation changes implemented in this book from Mod Level ..................... A03 to A04 (Jan 2010)

Pipework layout changes to tank module & various other changes throughout book.

Ideal Stelrad Group reserve the right to vary specification without notice

3istor system store - Installation and Servicing

GENERAL

Table 1 - General Data

Boiler size istor HE260 istor HE325
Gas supply 2H - G20 - 20mbar
Gas Supply Connection Rc 1/2 (1/2” BSP female)
Injector size Stereomatic 5.6mm dia.
Inlet Connection Domestic Hot Water 22mm copper
Outlet Connection Domestic Hot Water 22mm copper
Flow Connection Central Heating 22mm copper
Return Connection Central Heating 22mm copper
Flue Terminal Diameter mm (in) 100 (4)
Average flue temp/mass flow rate (DHW) 74
Maximum Working Pressure (Sealed Systems) bar (lb/in

2

) 2.5 (36.3)
Maximum Domestic Hot Water Inlet Pressure bar (lb/in2) 10.0 (145)
Minimum Domestic Hot Water Inlet Pressure bar (lb/in2) 0.5 (7)
Maximum Domestic Hot Water Outlet Pressure bar (lb/in2) 2.0 (29)
Temperature & Pressure relief valve Preset 95
Electrical Supply / Power consumption 230 V ~ 50 Hz. / 148 W
Fuse Rating External : 3A Internal : 3.15A TL250 V
Water content Central Heating litre (gal) 2.0 (.44)

Domestic Hot Water 80 litre 120 litre
Packaged Weight - Boiler box kg (lb) 58.5 (129) 58.5 (129)
Packaged Weight - Tank box kg (lb) 66 (145) 73 (161)
Maximum Installation Weight -Boiler box kg (lb) 55 (121) 55 (121)
Maximum Installation Weight -Tank box kg (lb) 59 (130) 65 (143)
Boiler Casing Size Height mm (in) 1400 (55) 1600 (63)

Width mm (in) 560 (22) 560 (22)

Depth mm (in) 600 (23.6) 600 (23.6)

Potable water components on tank module

Pressure reducing valve preset to 2 bar
Thermostatic mixer max inlet temp 85
Pressure and temp relief valve on cylinder 90
Pressure relief valve on inlet manifold 3 bar
DHW expansion vessel 19 litres, precharged to 2 bar

o

C / 20.3g/s

o

C / 4.0 Bar opening

o

C/max pressure 14 bar

o

C and 4 bar

Table 2 - Performance Data - Central Heating

Boiler Input : Max. Min.

Nett CV kW 24.4 9.1

(Btu/h) (83 300) (31 000)

Gross CV kW 27.1 10.1

(Btu/h) (92 500) (34 400)

Gas Consumption l/s 0.70 0.26

3

/h) (89.1) (33.2)

(ft

Boiler Output :

Non Condensing kW 23.4 8.8

(Btu/h) (80 000) (30 000)

Condensing kW 25.1 9.6

(Btu/h) (83 700) (32 800)
Seasonal efficiency (SEDBUK)* Band A [90.1]%
NOx Classification Class 5

Table 3 - Performance Data - Domestic Hot Water

Maximum DHW Input : Nett CV kW 30.2

(Btu/h) (103 100)

Gross CV kW 33.5

(Btu/h) (114 300)

Gas Consumption l/s 0.87

3

(ft

/h) (110)

Maximum DHW Output kW 29.3

(Btu/h) (100 000)
DHW Storage Temp 70
DHW Delivery Temp Factory set 60
Variable on Installation only 45

o

C

o

C

o

C-65oC
DHW Flow Rate HE260 HE325
(Practical maximum assuming
suitable mains supply) l/min 35 35
DHW Recovery from 15

0

C min. 14 20

After 70% draw off min. 9 12

* The value is used in the UK Government's Standard Assessment Procedure (SAP) for energy rating of dwellings. The test data from

which it has been calculated have been certified by a notified body.

Note. Gas consumption is calculated using a
calorific value of 38.7 MJ/m

3

(1038 Btu/ft3)

gross or 34.9 MJ/m3 (935 Btu/ft3) nett

To obtain the gas consumption at a different
calorific value:

a. For l/s - divide the gross heat input (kW) by

the gross C.V. of the gas (MJ/m

b. For ft

3

/h - divide the gross heat input (Btu/

3

)

h) by the gross C.V. of the gas (Btu/ft3)

Key to symbols

IE = Ireland, GB = United Kingdom (Countries of destination)

PMS = Maximum operating pressure of water

C

13 C33 C53

= A room sealed appliance designed for connection via ducts to a

horizontal or vertical terminal, which admits fresh air to the burner
and discharges the products of combustion to the outside through
orifices which, in this case, are concentric. The fan is up stream
of the combustion chamber.

I

= An appliance designed for use on 2nd Family gas, Group H only.

2H

CAUTION.

To avoid the possibility of injury during the installation, servicing or cleaning

of this appliance, care should be taken when handling edges of sheet steel components.

4

istor system store - Installation and Servicing

GENERAL

ti

m

e

P
R
O

G
R
A
M

M
E
R

p
rog

p
r
o
g

sele

c
tse

l
e

c
t

+

-

istor

Natural Gas only

Boiler size G.C. Appliance No. PI No.

(Benchmark No.)

HE260 41-394-13 87 BP 34

HE325 41-394-14 87 BP 34

Destination Countries: UK, IE

ist9826

CONTENTS

Air Supply ..................................................................... 10

Benchmark Commissioning Checklist ..................... 74

Boiler Clearances ......................................................... 8

Boiler Exploded Diagram ................................. 15,16,17

Condensate Drain ............................................ 10,22,23

Electrical Connections ............................................... 36

Electrical Supply ......................................................... 10

Extension Ducts - Fitting ............................................. 30

Fault Finding ........................................................... 65-69

Flow Wiring Diagram .................................................. 39

Flue Installation ..................................................... 26-34

Gas Safety Regulations ................................................ 7

Gas Supply ..................................................................... 9

Installation ............................................................. 16-42

Mandatory Requirements ....................................... 7-15

Pump .......................................................................... 60

Safe Handling ................................................................ 6

Servicing ................................................................ 43-64

Short List of Parts ....................................................... 70

Thermostatic Radiator valves ................................... 10

Water and Systems .............................................. 12-15

Water Connections ............................................... 19-20

Water Treatment ......................................................... 15

Wiring Diagrams ................................................... 36-39

For GB, to comply with Building Regulations Part L1 (Part 6 in Scotland) the boiler should be fitted in accordance with the
manufacturer's instructions. Self-certification that the boiler has been installed to comply with Building Regulations can be
demonstrated by completing and signing the Benchmark Commissioning Checklist.

Before installing this boiler read the Code of Practice sheet at the rear of this book.

BENCHMARK COMMISSIONING CHECKLIST DETAILS

Boiler Page

Make and model .......................................................5

Appliance serial no. on data badge ....... Front Cover

SEDBUK No. % ......................................................... 4

Controls

Time and temperature control to heating ............. 37

Time and temperature control to hot water .......... 37

Heating zone valves .............................................. n/a

TRV's ...................................................................... 1 0

Auto bypass ........................................................... 10

Boiler interlock ....................................................... 10

For all boilers

Flushing to BS.7593 .............................................. 15

Inhibitor .................................................................. 15

Central heating mode

Heat input ................................................to be calculated

Burner operating pressure ...... measure and record

Central heating flow temp. ...... measure and record

Central heating return temp. ... measure and record

For combination boilers only

Scale reducer ......................................................... n/a

Hot water mode

Heat input ............................................................... n/a

Max. operating burner pressure .............................. n/a

Max. operating water pressure .............................n/a

Cold water inlet temp ............................................ n/a

Hot water outlet temp. ........................................... n/a

Water flow rate at max. setting ..............................n/a

For condensing boilers only

Condensate drain .................................................. 22

For all boilers: complete, sign & hand over to customer

For assistance see Technical Helpline on the back page

Page

NOTE TO THE INSTALLER:

COMPLETE

THE BENCHMARK COMMISSIONING

CHECKLIST AND LEAVE THESE

INSTRUCTIONS WITH APPLIANCE

5istor system store condensing - Installation and Servicing

GENERAL

r

DHW

Expansion

Vessel

DHW

Mixer Valve

Tundish

DHW

Temp. &

Pressure

Relief Valve

Hot Water Out

Cold Water In

ist9830

INTRODUCTION

The istor HE260 & HE325 boilers are a fully automatically controlled,

condensing, system store, fanned flue, gas boiler.

Note. Due to the high efficiency of the boiler a plume of water vapour
will form at the terminal during operation.

Central heating (CH) output is fully modulating with a range of:

8.8 to 23.4kW (30,000 to 80,000 Btu/h)

Domestic hot water (DHW) output to the cylinder is also fully
modulating with a maximum of:

29.3kW (100,000 Btu/h)

The boiler is supplied fully assembled with an unvented DHW cylinder,
diverter valve, circulating pump, CH & DHW expansion vessels,
pressure gauge, safety valves, thermostatic mixer valve. A pressure
reducing valve is supplied for fitting externally to the boiler.

Variable CH temperature control is fitted on the user control.

A programmer is fitted as standard and may be remotely monitored
away from the boiler using remote monitoring kit.

The boiler casing is of white painted zintec coated mild steel.

The boiler temperature controls are visible at the middle RHS of the
front panel.

The heat exchanger is of cast aluminium.

The DHW cylinder is made of copper with a rapid recovery coil and
produces mains pressure hot water to a maximum pressure of 2 bar.

The system pipework MUST include drain cocks in appropriate places.
A pre-piping frame is provided with the boiler which allows pipework to
be made to the boiler before installation of the tank module and boiler
module.

Note. Prior to installation this appliance must be stored in a dry, upright
condition.
Due note should be taken of the carton labelling when handling this
appliance.

1

BOILER WATER CIRCUIT DIAGRAMS

CENTRAL HEATING CIRCUIT

Pump

Diverte
Val ve

Filling
Loop

CH
Pressure
Gauge

Pressure
Relief
Outlet

ist9829

CH Flow

CH Return

DOMESTIC HOT WATER CIRCUIT

OPERATION

With no demand for CH the boiler fires only when DHW is drawn off, or
periodically for a few seconds without any DHW draw-off, in order to
maintain the DHW cylinder in a heated condition.

When there is a demand for CH, the heating system is supplied at the
selected temperature of between 30

o

C and 82 oC, until DHW is drawn
off. The full output from the boiler is then directed via the diverter valve
to the cylinder coil to satisfy the cylinder store temperature of 70oC.

DHW temperature is controlled to a factory set 60
mixer valve. This is adjustable on installation.

o

C via a thermostat

The boiler features a comprehensive diagnostic system which gives
detailed information on the boiler status when operating, and
performance of key components to aid commissioning and fault
finding.

SAFE HANDLING

This boiler may require 2 or more operatives to move it to its
installation site, remove it from its packaging base and during
movement into its installation location. Manoeuvring the boiler may
include the use of a sack truck and involve lifting, pushing and pulling.

Caution should be exercised during these operations.

Operatives should be knowledgeable in handling techniques when
performing these tasks and the following precautions should be
considered:

• Grip the boiler at the base.

• Be physically capable.

• Use PPE as appropriate, e.g. gloves, safety footwear.

During all manoeuvres and handling actions, every attempt should be
made to ensure the following unless unavoidable and/or the weight is
light.

6

• Keep back straight.

• Avoid twisting at the waist.

• Avoid upper body/top heavy bending.

• Always grip with the palm of the hand.

• Use designated hand holds.

• Keep load as close to the body as possible.

• Always use assistance if required.

istor system store - Installation and Servicing

GENERAL

OPTIONAL EXTRA KITS

• Flue Kits (for more details see page 11)

• Condensate pump Kit

o

• 90

Elbow Kit (max 4 elbows/ installation)

o

• 45

Elbow Kit (max 4 elbows/ installation)

• Concentric Flue Screw Retaining Kit

• Remote User controls (for remote monitoring of

programmer)

• Horizontal Flue Kit. 600mm long

• High Level Flue Kit

• Pre-piping Frame Kit

• Adjustable flue support bracket

SAFETY

Installation of this boiler as an unvented hot water system falls
within the scope of the Building Regulations 1995 (Part G).
These require that installation of an ‘unvented’ system shall be
notified to the local authority Building Control Department: also
that the work must be carried out by a competent person as
defined in the Approved Document G3.

Current Gas Safety (installation and use) regulations or rules
in force:

The appliance is suitable only for installation in GB and IE and
should be installed in accordance with the rules in force.

In GB, the installation must be carried out by a Gas Safe
Registered Engineer. It must be carried out in accordance with
the relevant requirements of the:

• Gas Safety (Installation and Use) Regulations

• The appropriate Building Regulations either The Building

Regulations, The Building Regulations (Scotland), Building
Regulations (northern Ireland).

• The Water Fittings Regulations or Water byelaws in

Scotland.

• The Current I.E.E. Wiring Regulations.

Where no specific instructions are given, reference should be
made to the relevant British Standard Code of Practice.

In IE, the installation must be carried out by a Registered Gas
Installer (RGII) and installed in accordance with the current
edition of I.S.813 "Domestic Gas Installations", the current
Building Regulations and reference should be made to the
current ETCI rules for electrical installation.

Detailed recommendations are contained in the following British
Standard Codes of Practice:

BS. 5440:1 Flues (for gas appliances of rated input not

exceeding 70 kW).

BS. 5440:2 Ventilation (for gas appliances of rated input not

exceeding 70 kW).

BS. 5449 Forced circulation hot water systems.

BS. 5546 Installation of gas hot water supplies for

domestic purposes (2nd Family Gases)

BS. 6798 Installation of gas fired hot water boilers of rated

input not exceeding 60 kW.

BS. 6891 Low pressure installation pipes.

Health & Safety Document No. 635.

The Electricity at Work Regulations, 1989.

The manufacturer’s notes must NOT be taken, in any way, as
overriding statutory obligations.

IMPORTANT. These appliances are CE certificated for safety
and performance. It is, therefore, important that no external
control devices, e.g. flue dampers, economisers etc., are
directly connected to these appliances unless covered by these
Installation and Servicing Instructions or as otherwise
recommended by Ideal Stelrad Group in writing. If in doubt
please enquire.

Any direct connection of a control device not approved by Ideal
Stelrad Group could invalidate the certification and the normal
appliance warranty. It could also infringe the Gas Safety
Regulations and the above regulations.

SAFE HANDLING OF SUBSTANCES

Care should be taken when handling the boiler insulation
panels, which can cause irritation to the skin. No asbestos,
mercury or CFCs are included in any part of the boiler or its
manufacture.

LOCATION OF BOILER AND FLUE OUTLET

The boiler is floor mounted. The floor must be capable of
adequately supporting the weight of the boiler and any ancillary
equipment.

The boiler may be fitted on a combustible floor and insulation
between the floor and the boiler is not necessary, unless
required by the local authority.

For electrical safety reasons there must be no access available
from the back of the boiler.

The boiler must not be fitted outside.

Timber Framed Buildings

If the boiler is to be fitted in a timber framed building it should be
fitted in accordance with the Institute of Gas Engineering
document IGE/UP/7:1998.

Where installation will be in an unusual location, special
procedures may be necessary and BS 6798 gives detailed
guidance on this aspect.

Compartment Installations

A compartment used to enclose the boiler should be designed
and constructed specially for this purpose.

An existing cupboard or compartment may be used, provided
that it is modified for the purpose.

In both cases, details of essential features of cupboard /
compartment design, including airing cupboard installation, are
to conform to the following:

• BS 6798 (No cupboard ventilation is required - see air
supply for details).

• The position selected for installation MUST allow adequate
space for servicing in front of the boiler.

• For the minimum clearances required for safety and
subsequent service, see Frame 2. In addition, sufficient
space may be required to allow lifting access for the boiler
module.

7istor system store condensing - Installation and Servicing

GENERAL

ist9828

119.5 (4 3/4") Cold mains feed

2 BOILER DIMENSIONS, SERVICES & CLEARANCES

The boiler connections are made on the boiler piping frame.
Refer to Frame 23.

The following minimum clearances must be maintained for
operation and servicing.

Additional space will be required for installation, depending
upon site conditions.

Side and Rear Flue
a Provided that the flue hole is cut accurately, e.g. with a core

drill, the flue can be installed from inside the building where
wall thicknesses do not exceed 600mm (24"). Where the
space into which the boiler is going to be installed is less
than the length of flue required the flue must be fitted from
the outside.

Installation from inside ONLY
b. If a core boring tool is to be used inside the building

the space in which the boiler is to be installed must
be at least wide enough to accommodate the tool.

Front clearance

The minimum front clearance when built in to a cupboard is
5mm (1/4") from the cupboard door but 450mm (17 3/4")
overall clearance is still required, with the cupboard door open,
to allow for servicing.

If fitted to minimum clearances, the following dimensions
apply:

Boiler HE260 HE325

LH Flue Dim A m m 1477 1677

RH Flue Dim B m m 1480 1680

Rear Flue Dim C m m 1476 1676

all dimensions in mm (in)

8

istor system store - Installation and Servicing

GENERAL

GAS SUPPLY

The local gas supplier should be consulted, at the installation
planning stage, in order to establish the availability of an
adequate supply of gas. An existing service pipe must NOT be
used without prior consultation with the local gas supplier.

The boiler MUST be installed on a gas supply with a governed
meter only.

A gas meter can only be connected by the local gas supplier or
by a Gas Safe Registered Engineer. In IE by a Registered Gas
Installer (RGII).

An existing meter should be checked, preferably by the gas
supplier, to ensure that the meter is adequate to deal with the
rate of gas supply required.

It is the responsibility of the Gas Installer to size the gas
installation pipework in accordance with BS6891:2005. Whilst
the principle of the 1:1 gas valve ensures the istor range is
able to deliver it’s full output at inlet pressures as low as
14mb, other gas appliances in the property may not be as
tolerant. When operating pressures are found to be below the
minimum meter outlet of 19mb these should be checked to
ensure this is adequate for correct and safe operation.

Allowing for the acceptable pressure loss of 1mb across the
installation pipework, it can be assumed that a minimum
permitted operating pressure of 18mb will be delivered to the
inlet of the appliance. (Reference BS 6400-1 Clause 6.2
Pressure Absorption).

The integral appliance isolation valve and boiler pipework
could further reduce the operating pressure by up to 1.5mb
when measured at the inlet test point on the appliance gas
valve. Therefore it has been identified that an operating
pressure as low as 16.5mbar could be measured at the
appliance inlet pressure test point on the gas valve.

IMPORTANT.

Installation pipes must be fitted in accordance with BS.6891.
In IE refer to IS.813:2002. Pipework from the meter to the boiler
MUST be of an adequate size.

The complete installation MUST be tested for gas tightness
and purged as described in the above code.

FLUE INSTALLATION

Pluming will occur at the terminal so terminal positions where
this could cause a nuisance should be avoided.

The flue must be installed in accordance with the
recommendations of BS. 5440-1: 2000. In IE refer to I.S.
813:2002.

Do not use pipes of a smaller size than the boiler inlet gas
connection.

The following notes are intended for general guidance:

1. The boiler MUST be installed so that the terminal is
exposed to external air.

2. It is important that the position of the terminal allows the
free passage of air across it at all times.

3. Minimum acceptable spacing from the terminal to
obstructions and ventilation openings are specified in Table 4.

4. Where the lowest part of the terminal is fitted less than 2m
(6'6") above a balcony, above ground or above a flat roof to
which people have access then the terminal MUST be
protected by a purpose designed guard.

Terminals guards are available from boiler suppliers. In
case of difficulty seek advice from:

Grasslin (UK) Ltd.,
Tower House, Vale Rise, Tonbridge, Kent TN9 1TB
Tel. [phone] / Fax. [phone]
www.tfc-group.co.uk

Ensure that the guard is fitted centrally.

Table 4 - Balanced Flue Terminal Position

Flue Terminal Positions

1. Directly below or alongside an opening

window, air vent or other ventilation opening. 300mm (12")

2. Below guttering, drain pipes or soil pipes. 25mm ( 1")*

BS5440-1 2000 75mm (3")

3. Below eaves. 25mm (1")*

BS5440-1 2000 200mm (8")

4. Below balconies or a car port roof. 25mm (1")*

BS5440-1 2000 200mm (8")

5. From vertical drain pipes or soil pipes. 25mm (1")*

BS5440-1 2000 150mm (6")

6. From an internal or external corner or to a 25mm (1")*
boundary along side the terminal. BS5440-1 2000 300mm (12")

7. Above adjacent ground, roof or balcony level. 300mm (12")

8. From a surface or a boundary facing the terminal. 600mm (24")

9. From a terminal facing a terminal. 1,200mm (48")

10. From an opening in a car port

(e.g. door or window) into dwelling. 1,200mm (48")

11. Vertically from a terminal on the same wall. 1,500mm (60")

12. Horizontally from a terminal on the wall. 300mm (12")

Vertical Terminals

13. Above the roof pitch with roof slope of all angles. 300mm (12")

Above flat roof. 300mm (12")

14. From a single wall face. 300mm (12")
From corner walls 300mm (12”)

15. Below velux window 2000mm (79”)

16. Above or side of velux window 600mm (24”)

* Only one reduction down to 25mm is allowable per installation
otherwise BS5440-1 2000 dimensions must be followed.

Min. Spacing*

For RH Side Flues

- If the appliance is installed at minimum clearance from a
standard cavity wall the horizontal flue kit (600mm long) is
required.

- If the telescopic flue kit is used, an additional ‘D’ Pack
Extension will be needed.

For LH Side and Rear Flues

- For minimum clearance from standard cavity wall the
telescopic flue kit only is required.

5. Where the terminal is fitted within 850mm (34") of a
plastic or painted gutter or 450mm (18") of painted eaves
then an aluminium shield at least 750mm (30") long
should be fitted to the underside of the gutter or painted
surface fitted centrally above the flue.

6. The air inlet/products outlet duct and the terminal of the
boiler MUST NOT be closer than 25mm (1") to
combustible material. Detailed recommendations on the
protection of combustible material are given in BS. 5440:
Part 1, 2000. In IE refer to IS 813:2002.

IMPORTANT. It is absolutely essential to ensure, in practice,
that products of combustion discharging from the terminal
cannot re-enter the building or any other adjacent building
through ventilators, windows, doors, other sources of
natural air infiltration, or forced ventilation / air conditioning.

If this should occur the appliance MUST be turned OFF,
labelled as 'unsafe' until corrective action can be taken.

9istor system store condensing - Installation and Servicing

GENERAL

TERMINAL

The terminal assembly can be adapted to accommodate
various wall thicknesses. Refer to Frame 26.

AIR SUPPLY

It is NOT necessary to have a purpose-provided air vent in the
room or internal space in which the boiler is installed. Neither
is it necessary to ventilate a cupboard or compartment in
which the boiler is installed, due to the low surface
temperatures of the boiler casing during operation; therefore
the requirements of BS 6798, Clause 12, and BS 5440:2 may
be disregarded. In IE the requirement of IS 813:2002 may be
disregarded.

WATER CIRCULATION SYSTEM

The central heating system should be in accordance with BS.
6798 and, in addition, for smallbore and microbore systems,
BS. 5449.

Draining taps MUST be located in accessible positions, which
permit the draining of the whole system. They should be at
least 1/2" BSP nominal size and be in accordance with BS

2879.

WATER TREATMENT - see Frame 9

ELECTRICAL SUPPLY

WARNING. This appliance MUST be earthed,

Wiring external to the appliance MUST be in accordance with
the current I.E.E. (BS.7671) Wiring Regulations and any local
regulations which apply. For IE reference should be made to
the current ETCI rule for electrical installations.

The point of connection to the mains should be readily
accessible and adjacent to the boiler.

Note. The fan voltage is 325V DC.

CONDENSATE DRAIN - Refer to Frame 19

A condensate drain is provided on the boiler. This drain must
be connected to a drainage point on site. All pipework and
fittings in the condensate drainage system MUST be made of
plastic - no other materials may be used.

IMPORTANT.

Any external runs must be insulated

The drain outlet on the boiler is standard 3/4in (21.5mm)
overflow pipe.

THERMOSTATIC RADIATOR VALVES (TRV)

Ideal Stelrad Group recommend that heating systems utilising

full thermostatic radiator valve control of temperature in
individual rooms should also be fitted with a room thermostat
controlling the temperature in a space served by radiators not
fitted with such a valve as stated in BS. 5449.

When thermostatic radiator valves are used, the space heating
temperature control over a living area having a heating
requirement of at least 0.9kW (3000Btu/h) of the boiler heat
output should be achieved using a room thermostat whilst
other rooms are individually controlled by thermostatic radiator
valves. A higher proportion of TRVs may be used, provided that
a bypass between the boiler flow and return is fitted, to ensure
adequate flow when all TRVs are closed - however this is NOT
recommended as a large proportion of TRVs can restrict water
circulation and inhibit the condensing mode of condensing
boilers, reducing fuel economy.

For further information refer to the 'Good Practice Guide 143', a
publication of the Energy Efficiency Office, available from the
Building Research Establishment, Garston, Watford WD2 7JR.
Tel: [phone].

10

istor system store - Installation and Servicing

ist9827

Roof flue kit (to a maximum of 7.5m)

100mm Concentric flue
(to maximum flue length of 6m)

Powered Vertical Flue Kit (typical installation
maximum 5m primary with 17m secondary)
For detailed maximums refer to
Powered Vertical Kit Instructions.

3

FLUING OPTIONS

GENERAL

11istor system store condensing - Installation and Servicing

GENERAL

4

SYSTEM REQUIREMENTS - Central Heating

Notes

a. The method of filling, refilling, topping up or flushing sealed

primary hot water circuits from the mains via a temporary
hose connection is only allowed if acceptable to the local
water authority.

b. Antifreeze fluid, corrosion and scale inhibitor fluids suitable

for use with boilers having aluminium heat exchangers may
be used in the central heating system.

Advice should be sought from a local water treatment
company.

General

1. The installation must comply with all relevant national and

local regulations.

2. The installation should be designed to work with flow
temperatures of up to 82 oC.

3. All components of the system must be suitable for a working
pressure of 3 bar and temperature of 110 oC. Extra care
should be taken in making all connections so that the risk of
leakage is minimised.

The following components are incorporated within the
appliance for the central heating:

a. Circulating pump.

b. Safety valve, with a non-adjustable preset lift pressure

of 3 bar.

c. Pressure gauge, covering a range of 0 to 6 bar.

d. A 8-litre expansion vessel, with an initial charge pressure

of 1.0 bar.

e. Diverter valve.

f. Filling loop.

4. 'Make-up' Water. Provision is made for replacing water loss

from the system, via a filling loop supplied and fitted to the
appliance.

Note.

The maximum cold water capacity of the system should
not exceed 143 litres, if not pressurized. However, if the
system is to be pressurized, the efficiency of the
expansion vessel will be reduced and a larger vessel (or
smaller system volume) may be necessary. If the capacity
of the vessel is not considered sufficient for this, or for any
other reason, an additional vessel MUST be installed on
the return to the boiler.

Guidance on vessel sizing is given above.

5. Filling. The system should be filled by the following
method:

a. Through the filling loop fitted to the appliance.

Connecting the inlet manifold to the CH return.

i. Thoroughly flush out the whole system with

cold water.

ii. Fill and vent the system until the pressure

gauge registers 1.5 bar, and examine for leaks.

iii. Check the operation of the safety valve by

raising the water pressure until the valve lifts.
This should occur within 0.3 bar of the preset lift
pressure.

iv. Release water from the system until the

minimum system design pressure is reached;

1.0 bar if the system is to be pre-pressurised.

Safety valve setting bar 3.0

Vessel charge pressure bar 0.5 to 0.75

System pre-charge pressure bar None 1.0

System volume Expansion vessel

(litres) volume (litres)

25 1.6 1.8

50 3.1 3.7

75 4.7 5.5

100 6.3 7.4

125 7.8 9.2

150 9.4 11.0

175 10.9 12.9

190 11.9 14.0

200 12.5 14.7

250 15.6 18.4

300 18.8 22.1

For other system volumes
multiply by the factor across 0.063 0.074

Water Flow Rate and Pressure Loss

Max CH Output kW 23.4

(Btu/h) (80 000)

Water flow rate l/sec 0.37

(gal/min) 4.8

Temperature Differential

Head available for m.w.g. 2.3

system pump. (ft.w.g.) 7.5

o

C15

o

F) (27)

(

12

istor system store - Installation and Servicing

SYSTEM REQUIREMENTS - Domestic Hot Water

5

Domestic Hot Water Requirements (see note in Frame 14).

1. The domestic hot water service must be in accordance

with BS 5546 and BS 6700.

2. Refer to Table 1 for minimum and maximum working
pressures.

3. The boilers are suitable for connection to most types of
washing machine and dishwasher appliances.

4. When connecting to suitable showers, ensure that:
a. The cold inlet to the boiler is fitted with an approved

anti-vacuum or syphon non-return valve.

b. Hot and cold water supplies to the shower are of

equal pressure.

5. Hard Water Areas

Note.

Attention is drawn to the following extracts from the Building
Regulations 1991.

Regulation 11(1) (Giving of a building notice or deposit of
plans)
“Subject to the following provisions of this regulation, a
person who intends to carry out building work or to make a
material change of use shall:

a. Give to the local authority* a building notice in accordance

b. Deposit full plans with the local authority* in accordance

Regulation 12(4) (Particulars and plans where a building
notice is given)

“.......a building notice shall be accompanied by a statement

which specifies:
*Attention is drawn to regulation 18 (supervision of building
work otherwise than by local authorities).

a. The name, make, model and type of hot water storage

b. The name of the body, if any, which has approved or

c. The name of the body, if any, which has issued any current

Regulation 13(3) (Full plans)

“Full plans shall consist of:

a. Description of the proposed building work or material

Note.

Bye-laws of the appropriate Water Undertake also apply.

Discharge Pipework

It is a requirement of Building Regulation G3 that any
discharge from an unvented system is conveyed to where it is
visible, but will not cause danger to persons in or about the
building. The tundish and discharge pipes should be fitted in
accordance with requirements and guidance notes of
Building Regulation G3. The G3 Requirements and Guidance
section 3.9 are reproduced in the following sections.
Information Sheet No.33 available from the British Board of
Agrement gives further advice on discharge pipe installation.
For discharge pipe arrangements not covered by G3
Guidance or BBA Info sheet No.33 advice should be sought
from either your local Building Control Officer or Ideal Stelrad
Group.

G3 Requirement

“.....there shall be precautions..... to ensure that the hot water

Where the water hardness exceeds 200mg/litre, it is
recommended that a proprietary scale reducing device
is fitted into the boiler cold supply within the
requirements of the local water company.

with 12; or

with regulation 13”.

system to be installed;

certified that the system is capable of performing in a way
which satisfies the requirements of paragraph G3 of
Schedule 1;

registered operative identity card to the installer or
proposed installer of system.”

change of use, and the plans, particulars and statements

required by paragraphs (1) to (4) of regulation 12: and....”

GENERAL

discharged from safety devices is safely conveyed to where
it is visible but will not cause danger to persons in or about
the building.”

G3 Guidance SECTION 3.9

The discharge pipe (D1) from the vessel up to and including
the tundish is generally supplied by the manufacturer of the
hot water storage system. Where otherwise, the installation
should include the discharge pipe(s) (D1) from the safety
device(s). In either case the tundish should be vertical,
located in the same space as the unvented hot water
storage system and be fitted as close as possible and
within 500mm of the safety device e.g. the temperature relief
valve.

Note.

The tundish is factory fitted during manufacture of the istor.
The discharge pipe (D2) from the tundish should terminate
in a safe place where there is no risk to persons in the
vicinity of the discharge, preferably be of metal and:

a. Be at least one pipe size larger than the nominal outlet

size of the safety device unless its total equivalent
hydraulic resistance exceeds that of straight pipe 9m
long i.e. discharge pipes between 9m and 18m
equivalent resistance length should be at least two sizes
larger than the nominal outlet size of the safety device,
between 18 and 27m at least 3 sizes larger, and so on.
Bends must be taken into account in calculating the flow
resistance. Refer to
An alternative approach for sizing discharger pipes would
be to follow BS 67100:1987 specification for design
installation, testing and maintenance of services
supplying water for domestic use within buildings and
their curtilages. Appendix E. section E2 and table 21.

b. Have a vertical section of at least 300mm long, below the

tundish before any elbows or bends in the pipework.

c. Be installed with a continuous fall.
d. Have discharges visible at both the tundish and the final

point of discharge but where this in not possible or is
practically difficult there should be clear visibility at one or
other of these locations. Examples of acceptable
discharge arrangements are:
i. Ideally below a fixed grating and above the water

seal in a trapped gully.

ii. Downward discharges at low level; i.e. up to 100mm

above external surfaces such as car parks, hard
standings, grassed areas etc. are acceptable
providing that where children may play or otherwise
come into contact with discharges a wire cage or
similar guard is positioned to prevent contact whilst
maintaining visibility.

iii. Discharges at high level; e.g. into a metal hopper

and metal down pipe with the end of the discharge
pipe clearly visible (tundish visible or not) or onto a
roof capable of withstanding high temperature
discharges of water and 3m from any plastic
guttering system that would collect such discharges
(tundish visible).

iv. Where a single pipe serves a number of discharges,

such as in blocks of flats, the number served should
be limited to not more than 6 systems so that any
installation discharging can be traced reasonably
easily. The single common discharge pipe should
be at least on pipe size larger than the largest
individual discharge pipe (D2) to be connected. If
unvented hot water storage systems are installed
where discharges from safety devices may not be
apparent i.e. in dwellings occupied by blind , infirm
or disabled people, consideration should be given to

13istor system store condensing - Installation and Servicing

GENERAL

6

SYSTEM REQUIREMENTS - Domestic Hot Water (continued)

the installation of an electronically operated device to
warn when discharge takes place.

Note.

The discharge will consist of scalding water and steam.
Asphalt, roofing felt and non-metallic rain water goods may be
damaged by such discharges.

Worked example of discharge pipe sizing

The example below is for a G1/2
temperature relief valve with a discharge
pipe (D2) having 4 No. elbows and length
of 7m from the tundish to the point of
discharge.
From Table 1:
Maximum resistance allowed for a straight
length of 22mm copper discharge pipe
(D2) from a G1/2 temperature relief valve
is 9.0m
Subtract the resistance for 4 No. 22mm
elbows at 0.8m each = 3.2m.
Therefore the permitted length equates to

5.8m.

5.8m is less than the actual length of 7m

therefore calculate the next largest size.
Maximum resistance allowed for a straight
length of 28mm pipe (D2) from a G1/2
temperature relief valves equates to 18m.
Subtract the resistance of 4 No.28mm elbows at 1.0m each:

4.0m.

Therefore the maximum permitted length equates to:14m.
As the actual length is 7m a 28mm min (D2) copper pipe will
be satisfactory.

WARNINGS

z Under no circumstances should the factory fitted

temperature/pressure relief valve be removed other than
by authorised personnel. To do so will invalidate any
warranty claim.

z Table 1. Sizing if copper discharge pipe (D2) for common

temperature relief valve outlet sizes.

z Control and safety valves MUST NOT be tampered with.

Valve Minimum Minimum Maximum resistance Resistance
outlet discharge discharge allowed, expressed created by
size pipe D1 pipe D2 as a length of straight each elbow

G1/2 15mm 28mm up to18m 1.0m

G3/4 22mm 42mm up to 27m 1.7m

G1 28mm 42mm up to 18m 1.7m

z The discharge pipe MUST NOT be blocked or used for

any other purpose.

z The tundish must not be removed.
z Electrical components must not be sited near the

tundish.

from tunish pipe (i.e. no elbow or bends) or bend

22mm up to 9m 0.8m

35mm up to 27m 1.4m

28mm up to 9m 1.0m
35mm up to 18m 1.4m

35mm up to 9m 1.4m

54mm up to 27m 2.4m

The boiler does not normally need a bypass but at least
some radiators on the heating circuit, of load of at least
10% of the minimum boiler output, must be provided
with twin lockshield valves so that this minimum
heating load is always available. See note regarding
thermostatic radiator valves on page 10.

Note.

Systems incorporating zone valves which could
completely cut off the flow through the system, must be
wired such that the boiler will not fire or continue to fire
when this occurs.

14

istor system store - Installation and Servicing

7

SYSTEM BALANCING

GENERAL

BALANCING

1. Set the programmer CH Channel to ON.

Close the manual or thermostatic valves on all radiators,
leaving the twin lockshield valves (on the radiators referred
to above) in the OPEN position.

Turn up the room thermostat and adjust these lockshield
valves to give boiler flow and return temperatures not more
than 20

8

The istor boiler has an ALUMINIUM alloy heat exchanger

IMPORTANT.
The application of any other treatment to this
product may render the guarantee of Ideal Stelrad
Group invalid.

Ideal Stelrad Group recommend Water Treatment in

accordance with the Benchmark Guidance Notes on
Water Treatment in Central Heating Systems. Ideal
Stelrad Group recommend only the use of

or MB1, GE BETZ SENTINEL X100 or Salamander Corrosion

Guard inhibitors and associated water treatment products,
which must be used in accordance with the
manufacturers' instructions.

Domestic Hot water

In hard water areas where main water can exceed
200ppm Total Hardness (as defined by BS 7593:2006
Table 2) a scale reducing device should be fitted into the
boiler cold supply within the requirements of the local
water company. The use of artificially softened water,
however, is not permitted.

Ideal Stelrad Group recommend the use of Fernox
Qantomat, GE Betz Sentinel Combiguard and Calmag
CalPhos I scale reducing devices, which must be used in
accordance with the manufacturers' instructions.
For further information contact:

o

C apart.

WATER TREATMENT

FERNOX-COPAL

These valves should now be left as set.

2. Open all manual or thermostatic radiator valves and
adjust the lockshield valves on the remaining radiators,
to give around 15

3. Adjust the room thermostat and programmer to NORMAL
settings.

Fernox Manufacturing Co. Ltd.
Cookson Electronics
Forsyth Road
Sheerwater Woking
Surrey GU21 5RZ
[phone]

Salamander Engineering Ltd
The Heath Business &
Technical Park,
Runcorn,
Cheshire, WA7 4QX
Tel: [phone]

Notes.

1. It is most important that the correct concentration of the

water treatment product is maintained in accordance with
the manufacturers' instructions.

2. If the boiler is installed in an existing system any
unsuitable additives MUST be removed by thorough
cleansing. BS. 7593:2006 details the steps necessary to
clean a domestic central heating system.

3. In hard water areas, treatment to prevent lime scale may
be necessary - however, the use of artificially softened
water is NOT permitted.

4. Under no circumstances should the boiler be fired before
the system has been thoroughly flushed.

o

C temperature drop at each radiator.

Sentinel Performance Solutions
The Heath Business &
Technical Park, Runcorn,
Cheshire, WA7 4QX
Tel. [phone]
www.sentinel-solutions.net

Calmag Ltd.
Unit 4-6, Crown Works
Bradford Road
Sandbeds, Keighley
West Yorkshire BD20 5LN
Tel: [phone]

9

BOILER ASSEMBLY - Exploded View - Legend for Frames 10 & 11

1. Case sealing panel.

2. Sump cover plate.

3. Flue sensing nipple.

5. Flue manifold kit.

6. Flue manifold fixing.

7. Burner

8. Combustion chamber

insulation.

9. Heat engine.

10. Injector & housing.

11. Venturi kit.

12. Fan assembly.

13. Gas valve inlet pipe.

14. Auto air vent.

15. Gas cock.

16. Gas valve.

17. Fan fixing kit.

18. Orifice plate kit.

20. Thermistor (control/return)

21. Overheat thermostat.

22. Ignition electrode.

23. Flame detection electrode.

27. Condensate ’S’ trap.

29. User controls.

33. Mains switch

34. Spark generator.
34a. Ignition lead.

37. Prepiping frame.

45. Turret gasket kit.

55. Lower tundish Pipe.

56. DHW outlet Pipe.

59. Cold in pipe.

61. CH flow pipe.

66. Mains gas pipe.

67. Pressure relief valve pipe.

70. Tank pipe.

73. CH return assembly.

74. CH flow assembly.

77. Tank flow pipe (Top).

81. DHW expansion vessel.

82. CH expansion vessel.

83. Pump.

85. Divertor valve.

89. Thermostatic mixing valve.

90. Temp & pressure relief valve.

91. CH Pressure relief valve.

92. DHW Pressure relief valve.

93. Tundish assy.

95. Filling loop.

101. Pressure gauge.

102. Fascia controls assy.

103. Dry fire thermistor.

15istor system store condensing - Installation and Servicing

INSTALLATION

ist9831

3

45

10

9

11

1

14

23

22

2

16

103

7

8

18

12

6

17

20

20

21

27

13

83

61

85

14

34

34A

5

Data badge

10

BOILER MODULE ASSEMBLY - Exploded View

INSTALLATION

16

istor system store - Installation and Servicing

INSTALLATION

time

P
R
O

G
R

A
M

M
E

R

progp

r
o

g

s
elect

s
e
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t

+

-

102

106

105

104

105

33

29

15

91

37

74

77

70

84

107

108

101

73

59

56

55

95

93

92

89

67

107

90

83

16

81

82

ist9832

11

TANK MODULE ASSEMBLY - Exploded View

INSTALLATION

17istor system store - Installation and Servicing

12

ist9003

Corner

Protectors

Wooden

Packaging

Base

Sleeved front panel

(sleeve not shown)

Pre-piping

Frame

ist9893

BOILER PACKAGING AND REMOVAL

The boiler is supplied in two separate cartons. The tank
module carton includes the pre-piping frame, the hardware
pack, the literature pack and cardboard template.

The boiler module carton includes the controls facia panel
with integral programmer.

A telescopic flue assembly (if specified) for lengths up to
595mm, rear or side flue outlet, in Pack B.

Optional extras, If ordered, are available in separate boxes.

The tank module carton should be opened first and the
prepiping frame removed. It is unnecessary to unpack the
boiler module at this stage.

INSTALLATION

INSTALLATION

1. Ensure the tank module is stood correctly as marked on

the carton.

2. Remove the strapping.

3. Fold back the top flaps to gain access to the instructions,

the pre-piping frame and cardboard template.

4. Remove the instructions and read thoroughly.

5. UNSCREW THE RETAINING SCREWS AND REMOVE

THE PRE-PIPING FRAME FROM THE CARTON.

Note.

The appliance packaging may be left on for protection at this
stage, while all service pipes are made to the pre-piping
frame.

TANK MODULE BOILER MODULE

Hardware Pack Contents

A Mains connector assembly - 1 off
B Fibre sealing washer - 8 off
C Gas line sealing washer - 2 off
D 3/4” straight adaptor & nut - 1 off
E 15mm olive -1 off
F 15mm PRV nut -1 off
G M5 x 6 pp screw - 2 off
H M5 x 12 pp screw - 2 off
J Strain relief bush - 1 off
K Turret clamp - 1 off
L M5x10 p hex screw (turret fixing) - 1 off
M Pressure reducing valve (preset to 2 bar) - 1 off
N PRV lift lever - 1 off
P Pressure Relief Pipe - 1 off

Pack B Contents

A Telescopic flue terminal

B Flue turret

C Rubber Terminal Wall Seal

D Screw

E Sealing tape

A

B

B

C

D

E

F

K

H

M

P

G

J

A

L

D

E

N

ist9004

C

isfu8751d

18

istor system store - Installation and Servicing

INSTALLATION

ist8991

13

FITTING THE PRE-PIPING FRAME

1. Using the cardboard template mark the position of the

appliance and the fixing holes for the pre-piping frame.

2. Fasten the pre-piping frame to the floor.

Using suitable fixing screws and plugs dependant on the
floor material, fasten the pre-piping frame to the floor.
Take care not to pierce any underfloor piping or electrical
wiring.

Note.

Pipe runs to the service connections on the piping frame
must be from the front, back or below, and not cross the
side channels of the frame, where the appliance will slide
on and stand.

14

WATER (DHW) CONNECTIONS

Domestic Hot Water Connections

ist8339

INSTALLATION

Refer to the Note in Frame 13, for guidance.

IMPORTANT

Do not subject any of the isolating valves to heat as the
seals may be damaged.

The PRV (pressure reducing valve) provided in the
hardware pack MUST be fitted in a convenient point on
the mains cold inlet to the appliance. Once fitted, a
pressure balanced cold feed to mixer taps and
showers may be taken downstream of the PRV but
before the istor appliance.

Note.

1. The PRV has a built in serviceable water filter. It
must therefore be located in a suitable place for
future maintenance.

2. It is pre-set to deliver water to the istor at 2 bar to
ensure safe operation of the DHW system.

3. The pressure reducer can be installed with the
pipework either vertical or horizontal. However it
must not be installed upside down.

4. To obtain optimum DHW delivery from the
appliance all DHW pipes should be run in 22mm.

To taps and
showers

Hot
Out

Cold
In

Pressure balanced

cold feed to mixer
taps and showers

ist8337

Pressure
reducing
valve

Mains
cold in

Note.

When installing the PRV,
consideration should be given to
the use of isolation valves either
side of the PRV for future
servicing and maintenance.

19istor system store - Installation and Servicing

15

CH WATER CONNECTIONS

Central Heating connections

Refer to the Note in Frame 13 for
guidance.

IMPORTANT

Do not subject any of the isolating
valves to heat as the seals may be
damaged.

INSTALLATION

INSTALLATION

16

GAS CONNECTION

IMPORTANT.

The gas service cock is sealed with a
non-metallic fibre washer so must not
be overheated when making capillary
connections.

For additional gas supply information
refer to “Gas Supply” on page 9.

1. Extend a gas supply pipe of not less
than 15mm O.D. copper to the
boiler.

A working gas pressure of 20mbar
(8" w.g) should be available at the
boiler inlet, with the boiler firing at
full DHW output.

20

Fibre washer

Gas cock

(shown in the

open position)

GAS IN

ist8340

istor system store - Installation and Servicing

17

SAFETY VALVE DRAIN (DHW)

The discharge pipe should be
positioned so that the
discharge of water or steam
cannot create a hazard to the
occupants of the premises or
damage the electrical
components and wiring.

IMPORTANT.

The discharge pipe
arrangement must comply with
G3 Building Regulations. This
is covered in Frames 6 and 7.

INSTALLATION

INSTALLATION

18

SAFETY VALVE DRAIN (CH)

A preformed 15mm is supplied strapped to
the cylinder module frame. This pipe
connects to the safety valve, and projects
through the RH hole in the pre-piping
frame, for routing the drain under and away
from the appliance.

Note.

The length of this pipe is suitable for the
HE260 model. For the HE325 model
100mm should be cut off the longer
section.

21istor system store - Installation and Servicing

INSTALLATION

ist9837

19

CONDENSATE DRAIN

The condensate drain connection point position is shown in
the diagram below. A 700mm long flexible hose is supplied
strapped to the cylinder module frame and an adaptor is
provided in the hardware pack for connection to this. It may be
necessary to make provision for connection to this, prior to
moving the appliance into position.

Note.

A condensate pump kit is available for fitting outside of the
appliance, if the minimum fall of 1 in 20 away from the boiler,
throughout its length is not available.
If fitting this kit refer to the installation instructions within the
kit, otherwise follow the guidance below.

The condensate drain provided on the boiler must be

INSTALLATION

connected to a drainage point, preferably within the building.

Ensure that the condensate trap is full of water before
commissioning the boiler - refer to Frame 32.

The routing of the drain must be made to allow a minimum
fall of 1 in 20 away from the boiler, throughout its length.

The drainage pipework must be arranged so that obstruction
(e.g. through freezing) of external drainage pipe does not give
rise to spillage within the dwelling.

IMPORTANT.

Any external runs must be insulated.

Excessive external pipe runs should be avoided in order to
prevent possible freezing.

All pipework and fittings in the condensate drain system must
be made of plastic. No other materials may be used.

The drain outlet on the boiler is standard 21.5mm overflow
pipe. This size must not be reduced in any part of its length.

If external condensate pipe run is greater than 3m then pipe
must be 32mm nominal diamater. Consideration should be
given to insulating external condensate pipe runs.

In order to defer the onset of freezing of the condensate drain
when the pipe is run externally the pipe should be run as far
as possible within the building.

The boiler condensate drain connection is suitable for Marley
'Terrain' tubing.

A siphon kit is available to prevent freezing.

20

CONDENSATE PIPE TERMINATION CONFIGURATIONS

Notes: ALL EXTERNAL PIPE RUNS MUST BE IN ACCORDANCE WITH
BS6798

1. INTERNAL TO SINK WASTE

BOILER

UPSTREAM OF SINK WASTE
TRAP

2. INTERNAL TO SINK WASTE

cla7771a

BOILER

Air Break

DOWNSTREAM OF SINK
WASTE TRAP (PREFERRED
METHOD)

cla9252

75mm trap

Sink constitutes

air break

Sink

DRAIN

DRAIN

Open end of pipe
direct into gulley
below grating but
above water level

Ground Level

Open end of pipe
direct into gulley
below grating but
above water level

Ground Level

continued . . . . . .

22

istor system store - Installation and Servicing

21

BOILER

External

wall

Ground Level

Open end of pipe
direct into gulley
below grating but
above water level

DRAIN

cla7775

CONTINUED...

INSTALLATION

3. INTERNAL CONNECTION TO SOIL AND VENT STACK

Termination into a down pipe can take place providing it can be
confirmed that the down pipe is part of a combined waste and rain
water system.

* Make connection to SVP using a solvent welded saddle

4. TERMINATION TO SOAK AWAY

BOILER

cla7774

External

wall

BOILER

cla9253

to Soak away

minimum

500mm

Air Break

INSTALLATION

Termination

Ground Level

5. TERMINATION TO DRAIN / GULLEY

22

PACKAGING REMOVAL (TANK MODULE)

1. If the tank module is still packaged, lift out the

sleeved front panel and store to one side to avoid
damage.

Note.

Leave pipe nut protector in place to aid installation
onto piping the frame.

2. Remove and save the floor cardboard template.

3. Remove the packaging sleeve, corner protectors and

front protector.

4. Remove two front screws securing tank module to the
packaging base.

5. Slide module forward to free it from rear fixings.

Sleeved front panel

ist9005

23istor system store - Installation and Servicing

23

TANK CONNECTION TO THE PIPING FRAME

General

Before moving the appliance onto the piping frame provision
must be made for the condensate drain which may be
easier before the boiler is moved into position. Refer to
Frame 19.

1. Lift tank section over the piping frame and engage the
rear of the base onto the runner of the piping frame.

Note.

At this stage if the appliance is being fitted into a cupboard
with limited access it may be advisable to attach the boiler
module on top of the tank module prior to sliding into place.
If so refer to Frame 25 for attaching the boiler module.
(Note that the CH flow pipe is supplied strapped to the
cylinder module frame).

2. Slide the tank backward until the stops on the frame are

INSTALLATION

reached.

3. Remove the pipe nut protector from the cylinder module
pipe nuts.

4. The pipes can now be connected to the piping frame
once the transit bracket is removed (see illustration).

INSTALLATION

1

ist8992

24

BOILER MODULE PACKAGING AND REMOVAL

1. Ensure the boiler module is stood correctly as marked

on the carton.

2. Remove the strapping.

3. Fold back the top flaps and remove the top protector/

mounting template.

4. Lift off the packaging sleeve and corner protection and
discard.

5. Unscrew the 2 - M4 x 10 screws securing the front panel
and remove to one side to avoid damage.

6. Remove the controls fascia box and store to one side to
avoid damage.

Runners

Top protector/
Mounting template

24

ist9833

istor system store - Installation and Servicing