Ariston SOLARcomfort User guide

SOLARcomfort
Solar Hot Water
Systems
Pump Group Instructions for Installation
and Servicing
LEAVE THESE INSTRUCTIONS WITH THE
END USER
Country of Destination GB/IE

1
TABLE OF CONTENTS
1. GENERAL INFORMATION ................ 2
1.1 GUARANTEE .......................................... 2
1.2 SYSTEM CONTENTS ................................ 2
1.3 SYSTEM INSTRUCTION BOOKS ................... 2
1.4 SOLARCOMFORT .................................. 3
1.5 LIFESTYLE ............................................. 3
1.6 HOW THE SYSTEM WORKS ....................... 3
2. SAFETY ............................................. 6
3. TECHNICAL DATA ............................. 7
3.1 TEMPERATURE/PRESSURE ........................ 7
3.2 COMPONENT LIST ................................... 8
3.3 PUMP GROUP DIMENSIONS ...................... 9
3.4 EXPANSION VESSEL DIMENSIONS ............... 9
4. REGULATIONS & STANDARDS...... 10
4.1 WAT E R REGULATIONS ........................... 10
4.2 BUILDING REGULATIONS ......................... 10
4.3 GENERAL GUIDANCE ............................. 10
4.4 BRITISH & EUROPEAN STANDARDS .......... 11
4.5 UK REGULATIONS (WAT E R HEATING) ...... 11
4.6 UK REGULATIONS (CONSTRUCTION) ........ 11
4.7 EU DIRECTIVES ................................... 12
4.8 OTHER PUBLICATIONS ........................... 12
4.9 ELECTRICAL CONNECTION ...................... 12
4.10 THERMAL INSULATION ............................ 12
5. INSTALLATION ................................ 13
5.1 FITTING FLOW LIMITER .......................... 13
5.2 POSITIONING PUMP GROUP .................... 13
5.3 CONSIDERATIONS FOR POSITIONING PUMP
GROUP ............................................... 14
5.4 PIPEWORK AND FITTINGS ....................... 14
5.5 INSULATION .......................................... 14
5.6 SIZING OF PIPES .................................. 15
5.7 PIPEWORK ........................................... 15
5.8 ELECTRICAL CONNECTIONS .................... 15
5.9 TWO COLLECTOR SCHEMATIC ................. 17
5.10 THREE COLLECTOR SCHEMATIC .............. 17
5.11 WALL MOUNTING MODULES ................... 18
5.12 CONNECTING PIPEWORK ........................ 19
5.13 PIPE REDUCERS .................................. 20
5.14 EXPANSION VESSEL .............................. 20
5.15 PRESSURE RELIEF VALVE ...................... 21
5.16 FILLING POINT ..................................... 22
5.17 FLOW REGULATOR ................................ 22
6. COMMISSIONING SYSTEM ........... 23
6.1 PRE-FILL CHECK .................................. 23
6.2 FLUSHING AND FILLING THE SYSTEM USING
GLYCOL .............................................. 24
6.3 FLUSHING THE SYSTEM USING WATER ...... 26
6.4 FILLING AND TOPPING UP THE SYSTEM WITH
GLYCOL .............................................. 28
6.5 SYSTEM PRESSURE .............................. 30
6.6 COMMISSIONING SHEET ......................... 31
7. MAINTENANCE SCHEDULE .......... 32
this will be page 1

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1. GENERAL
INFORMATION
This manual is an integral and essential part of the product. It should be
kept with the product.
Please read carefully the instructions and notes about SOLARcomfort
contained in this manual as they provide important information regarding
the safe installation of the Pump Group.
IMPORTANT
Failure to follow these instructions correctly may invalidate the
guarantee.
IMPORTANT
Solar domestic hot water heating systems must be installed to
comply with the current Building Regulations, British Standards
and any applicable local regulations.
The SOLARcomfort Pump Group is guaranteed for 2 years against
munufacturing defect - see terms and conditions of guarantee on back
page.
The complete SOLARcomfort solar water heating system is supplied in
the following consignments:-
1. Ref. 800201 Collector 1 per box
2. Ref. 3107024/5 Roof Fittings Kit 1 cardboard tube
3. 3820011/2 System Components 1 box
4. 3820001 Tyfocor anti freeze heat transfer fluid
1 x 20l container
The following instruction booklets are supplied with a complete
SOLARcomfort solar water heating system:-
1. SOLARcomfort Solar Hot Water Systems Collectors 2 & 3 Collector
Set.
Covers collector installation and plumbing connection.
Supplied in System Components box.
2. SOLARcomfort Solar Hot Water Systems Pump Group 40/60.
Covers installation, plumbing connection, system filling, flushing and
commissioning.
Supplied in System Components box.
3. Solar Controller AST100
Covers installation, wiring connection and User Instructions.
Supplied in System Components box.
1.1 GUARANTEE
1.2 SYSTEM CONTENTS
1.3 SYSTEM INSTRUCTION BOOKS

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SOLARcomfort systems are highly efficient and provide cost savings on
the energy used for heating hot water wherever they are used in the UK.
However, the savings made will depend on local climate, installation
characteristics and the households use of hot water.
It is important that the SOLARcomfort system is correctly sized for the
local climate condition and the household’s domestic hot water
requirements.
After installation of the SOLARcomfort system, changes to the
householders use of hot water will be beneficial. Simple changes such as
bathing in the evening instead of the morning, and putting automatic
washing machines on when free hot water is available by solar energy.
In addition, the timing of the dwelling’s boiler controls must be modified to
ensure the ‘hot water ON’ time is set so that the water temperature in the
cylinder is at a minimum by the start of the ‘solar day’.
The solar collectors are heated by the sun’s rays. The heat generated is
stored in a hot water storage cylinder e.g. an Ariston Primo twin coil stainless
steel cylinder. The AST 100 Solar Controller continually compares the
temperature of the water within the cylinder with the temperature of the
solar collectors.
Whenever the solar collectors are hotter than the water within the cylinder,
the controller switches on the system’s circulating pump. The temperature
differential between the collectors and the cylinder is set via the AST100
Solar Controller. The heat transfer fluid within the solar system is then
circulated through the collectors and the cylinder’s heat exchanger, heating
the cylinder in just the same way as a central heating boiler.
The cylinder typically has two coils (heat exchangers), the lower coil is
heated by the solar system, therefore solar is the primary heat source.
The upper cylinder is heated by an auxiliary heat source, typically a central
heating boiler, which is used to heat water when there is insufficient heat
generated by the solar system. The Ariston Primo twin cylinder also has
two immersion heaters making it suitable for electric only heating systems.
The SOLARcomfort system is a forced circulation sealed system and
therefore requires an expansion vessel and a pressure relief valve (PRV),
both supplied with SOLARcomfort.
The air separator with an integral air vent together with an automatic air
vent positioned at the highest point on the system ensures that the sealed
system remains free of air.
1.6 HOW THE SYSTEM WORKS
See fig. 1.6A
1.4 SOLARCOMFORT
1.5 LIFESTYLE

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FIG. 1.6ABASIC PRINCIPLES
Roof mounted collectors
(two collector system shown)
Pump group
Expansion
vessel
Solar system
low level fill
point
Ariston ITSI 210/300
twin coil cylinder
Upper coil
heated by boiler
or other heat
source
Lower coil heated by
solar energy
AST 100
Controller
Air vent
PR Valve
Solar system
drain point
Temperature
Sensor S1
Temperature
Sensor S3
Temperature
Sensor S2 PRV discharge
vessel
Energy
Monitoring
Sensor S4
(option)

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FIG. 1.6BPUMP GROUP COMPONENTS
1. Insulated Cover
2. Flow from Solar Collectors
3. Flow Temperature Gauge
4. Flow Shut Off Valve
c/w non return valve -red Knob
5. Air Separator
6. Manual Air Vent
7. Return to Solar Collectors
8. Return Temperature Gauge
9. Return Shut Off Valve
c/w non return valve -blue Knob
10. Circulating Pump
11. System Fill and Drain Point
12. Fill and Drain Shut Off Valve
13. Flow Limiter
14. Flow Limiter Adjustment Screw
15. Non-return Valve
16. Non-return Valve Shut Off
17. Expansion Vessel Connection
18. Pressure Relief Valve (PRV)
19. PRV Outlet
20. System Pressure Guage
ReturnFlow

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2. SAFETY WARNING
The pump group must be correctly fitted to the wall using the bracket
supplied. It should not be supported by the connecting pipework
alone.
WARNING
During operation and commissioning the temperature of the heat
transfer fluid within the system and collectors can reach temperatures
high enough to present a risk of scalding. Never loosen fittings or
open vents when the system is hot.
WARNING
TYFOCOR LS Heat Transfer Fluid.
Although non-toxic it should not be swallowed.
Refer to label on its container for storage and safety information.
A detailed technical specification is available from Ariston on request.
Caution
SOLARcomfort should be installed and commissioned by approved
contractors. Failure to do so may invalidate the warranty.
Caution
The pump group should be positioned so that it is inaccessible to children
and cannot be tampered with.

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3. TECHNICAL DATA
Operating pressure and
temperature must be within
the limits depicted by the
hatched area
Operating temperatures above
100°C as depicted by the
shaded area must be avoided
for continuous operation
FIG. 3.1ATEMPERATURE PRESSURE DIAGRAM
3.1 TEMPERATURE / PRESSURE
PUMP MODULE
Pipe connection 22mm
Reducers supplied 15mm
Pump type 15/40
Maximum operating pressure 0.6MPa
Electrical Cable 1.0mm² 3 core heat resistant flex 3093Y to 85°C
Cover Moulded polystyrene
AIR SEPARATOR MODULE
Pipe connection 22mm
Reducers supplied 15mm
Maximum operating pressure 0.6MPa
Cover Moulded polystyrene
EXPANSION VESSEL
2 & 3 collector systems 25l
Optional size (code 12002737) 35l
Maximum pressure 10 bar
Pre-charge pressure 2.5 bar
PRESSURE RELIEF VALVE
Setting 6 bar
Discharge ½” BSP - Ø15 pipe
HEAT TRANSFER FLUID
Type Tyfocor LS
Use undiluted 100%
Weight 1.04kg/l
Frost protection to -28°C

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3.2 COMPONENT LIST
FIG. 3.2APUMP GROUP COMPONENT LIST
Listed below are all the components required to fit the pump group.
Item Description Qty
1 Pump Group 1
2 Flow Limiter Components (see 5.1) 1 set
3 Wall Mounting Bracket 1
4 Screw 1
5 Wall Plug 1
6 Expansion Vessel 25l standard (35l option) 1
7 Expansion Vessel Fixings 1
8 Flexible Connector 1

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FIG. 3.3APUMP GROUP DIMENSIONS
FIG. 3.4AEXPANSION VESSEL DIMENSIONS
25 Litre
(standard)
35 Litre
(optional: code 12002737)
3.3 PUMP GROUP DIMENSIONS
3.4 EXPANSION VESSEL DIMENSIONS
Maximum pressure 10 bar
Pre-charge pressure 2.5 bar

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4. REGULATIONS &
STANDARDS
SOLARcomfort hot water heating systems should be installed in
compliance with the following standards and regulations.
Water Supply (Water Fittings) Regulations 1999 / www.wras.co.uk
These regulations (bye-laws in Scotland) ensure a good supply of
wholesome water and that only approved materials, pipes and fittings are
used to convey water.
These are statutory documents and take priority over all other regulations
and recommendations. The installation of an unvented hot water storage
cylinder is classified as a “Controlled Service” and Regulation G3 applies.
To meet the requirements of the Regulations, installation of an unvented
system should be undertaken by a “competent installer”.
All installations of unvented hot water storage systems having a capacity
of more than 15 litres should be notified to the relevant Local Authority by
means of a building notice or by the submission of full plans. It is important
to note that it is a criminal offence to install an unvented hot water storage
system without notifying the Local Authority. The installation of the unvented
cylinder and hot water system must comply with BS 6700 and the HSE
Legionella Code of Practice.
Current guidance notes do not cover the connection of a solar thermal
circuit to an unvented storage vessel (cylinder). However, if guidance is
sought for compliance with current regulations the fundamental principle
is to provide a fail-safe means of shutting off the solar input to the heat
exchanger if the cylinder temperature should rise above the set temperature
of the cylinder’s energy cut out. (See Note 1).
As with all unvented hot water systems, notification of intention to install
should be given to your local building control.
Option A. A non self-resetting mechanical shut-off should be installed on
the solar primary flow to the cylinder. The mechanical shut-off should be
suitable for use with a solar primary circuit (i.e. high temperature and glycol
resistant). The mechanical shut-off should be integrated electrically with
the cylinder energy cut out/s and if necessary the solar circuit temperature
control, please refer to the solar controller manufacturer for further
information.
Option B. Where the solar controller and hydraulic system demonstrate
that by no lesser means the requirement in Option A is satisfied by other
means; certification by an approvals body is required to demonstrate that
in the event of the stored water going over temperature, the heat input to
the cylinder is isolated by physical means and is non self-resetting.
These systems should be clearly identified with reference to the approvals
body. (See Note 2).
Note 1 : Whilst most solar cylinders use a coil type heat exchanger other
options such as external plate to plate devices, external annulars or ‘tank
in tank’ systems may be used but the same control options always apply.
Note 2 : Current approved bodies include the British Board of Agrèment
(BBA), WRc-NSF Limited, or KIWA.
4.1 WATER REGULATIONS
4.2 BUILDING REGULATIONS
4.3 GENERAL GUIDANCE

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4.4 BRITISH & EUROPEAN
STANDARDS
Connection of thermal solar heating systems
EN 12976: Thermal solar heating systems and their components
(prefabricated systems).
ENV 12977: Thermal solar heating system and their components (bespoke
systems).
BS5918: Latest version: Solar heating systems for domestic hot water.
Installation and equipment of DHW cylinders
BS5546: 2000 Specification for installation of hot water supplies for domestic
purposes, using gas-fired appliances of rated input not exceeding 70 kW.
BS6700: 1997 Specification for design, installation, testing and
maintenance, of servicing, supplying water for domestic use within buildings
and their curtilages.
The local water company by-laws.
Electrical connection
Current IEE wiring regulations.
Health and Safety document No 635 (Electricity at Work Regulations)
The Pressure Equipment Regulations (PED) 1999 - www.eurodyn.com
The Building Regulations (L1 A&B) 2006 and Domestic Heating Compliance
Guide - www.communities.gov.uk
The Building Regulations (P) 2005 - www.communities.gov.uk
Control of Substances Hazardous to Health Regulations (COSHH) 1994 -
www.hse.gov.uk
Further details available from: www.hse.gov.uk
Health & Safety At Work Act (HSW) 1974
Work at Height Regulations 2005.
Reporting of Injuries, Diseases and Dangerous Occurrences Regulations
(RIDDOR) 1995.
Management Health & Safety at Work Regulations (MHSWR) 1999.
Noise at Work Regulations 1989.
Construction (Health, Safety & Welfare) Regulations (CHSWA) 1996.
Electricity at Work Regulations 1989.
Construction Regulations (Head Protection) 1989.
Control of Substances Hazardous to Health Regulations (COSHH) 1994.
Construction (Design and Management) Regulations (CDM) 1994.
Personal Protective Equipment at Work Regulations 1992.
Lifting Operations and Lifting Equipment Regulations (LOLER) 1998.
Confined Spaces Regulations 1997.
Manual Handling Operations Regulations 1992.
The Workplace (Health, Safety and Welfare) Regulations 1992 (WHSWA).
Provision and Use of Work Equipment Regulations (PUWER) 1998.
Health and Safety (First Aid) Regulations 1981.
LZC - Low or zero carbon energy sources: strategic guide.
4.5 UK REGULATIONS
PARTICULARLY RELEVANT FOR
WATER HEATING EQUIPMENT
4.6 UK REGULATIONS
PARTICULARLY RELEVANT FOR
CONSTRUCTION

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Further details available from: www.europa.eu.int
Construction Directive: 89/106/EEC
Electromagnetic: 89/336/EEC
Low voltage: 73/23/EEC
Machinery Directive: 98/37/EC
Preventing hot water scalding in bathrooms: using TMVs (IP 14/03).
DTI testing of solar systems (SP300275 1-3).
Review of issues related to active solar heating systems (SP300246).
Active solar performance and data review (SP300270).
Solar heating systems for hot water (BS 5918).
Hard water scale in hot water storage cylinders (IP13/93).
Heating systems in buildings – design for water-based heating systems
(PrEN 12828).
Building log books (GPG 348).
Solar heating (CIBSE DBSP WGG).
Sun in Action II (ESTIF – Sun in Action II).
Minimising the risk of legionnaires’ disease (TM 13).
BRE Digest 489.
Energy Saving Trust - www.est.org.uk
CE131 Solar Water Heating Systems - Guidance for professionals,
conventional indirect models.
BS7671 2001 Amended 2004
APD P:
P1 - Design, Installation, Inspection and Testing
P2 - Provision of information
Thermal Insulation Standard TIMSA (Thermal Insulation Manufacturers
and Suppliers Association).
4.7 EU DIRECTIVES
4.8 OTHER PUBLICATIONS
4.9 ELECTRICAL CONNECTION
4.10 THERMAL INSULATION

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5.2 POSITIONING PUMP GROUP
FIG. 5.2ASUGGESTED LOCATION
5. INSTALLATION
To Collector
Temperature
Sensor S1
From Collectors
To Collectors
AST 100
Controller
Cylinder
PRV
discharge
vessel
Fill point
Expansion
Vessel
Pump
Group
S3
S2
A flow limiter set is supplied separately, this must be fitted to the pump
group on the suction side of the pump as shown in fig. 5.1a.
FIG. 5.1AFITTING FLOW LIMITER
5.1 FITTING FLOW LIMITER
15Ø
Note:
The flow limiter is supplied with
fittings for 15Ø pipe.

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The pump group and should normally be wall mounted in close proximity
to the cylinder.
Fig. 5.2A gives a typical layout.
The AST100 Solar Controller should be positioned so that the householder
has easy access with good visibility of the display. Also, consideration has
to be given to routing for connection to the pump group, cylinder and
collector temperature sensors.
Cables supplied with the sensors and control unit are nominal length and
Consideration should be given to the following when selecting a position
for pump group:-
1. The pump group should be placed close to the storage cylinder to
keep pipe runs to a minimum.
2. The pump group and pipework should have easy access with good
visibility for changing settings and all necessary maintenance work.
3. The pump group and controller should be positioned so that they are
inaccessible to children and cannot be tampered with.
may require terminal boxes and extra cable lengths to make connections.
Taking into account the heat transfer fluid within the system may reach
high temperatures, the primary circuit should be copper, stainless steel
(rigid and flexible) or carbon steel braided high temperature hose. Pipe
joints and connections with other system components should also be able
to withstand the working temperatures and pressures. Thought should be
given to preventing corrosion due to dissimilar metals in contact.
All copper pipework must be Kite Marked BS EN1057 1996 Table X half
hard copper tube.
All fittings must be quality brass BS864-2 compression type.
Brass olives are recommended as they produce a better seal.
Brazed or silver soldered joints are acceptable.
The use of joint compounds such as ‘Fernox White’ is recommended for
compression joints.
Owing to the high temperatures of the solar system, plastic pipe and
fittings must not be used.
All fittings and components fitted must be able to withstand
temperatures in excess of 150°.
Soldered and push fit fittings should not be used.
Galvanised steel pipe should not be used.
All external pipework, connections and fittings must be insulated with
suitable high temperature, vermin resistant and UV resistant insulating
materials.
All internal pipework (excluding pipework to the expansion vessel) must
be insulated with suitable high temperature insulating materials.
Insulation of the pipework must only be undertaken after tightening
of the compression fittings and completion of a pressure test - see
section 6.
5.4 PIPEWORK AND FITTINGS
5.5 INSULATION
5.3 CONSIDERATIONS FOR
POSITIONING PUMP GROUP

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The flow rate in the circuit is between 0.5 and 1.5 litres/min for each collector.
The flow velocity in the circuit should not exceed 1.5m/sec otherwise the
the system may be noisy during operation.
As a guide only: systems with total pipework of less than 50 metres, 15mm
diameter pipe should allow flow conditions to be met for systems with up
to four collectors.
When the total pipework is over 50 metres, then 22mm pipe should be
used.
An assessment of the specific installation requirements must be
undertaken.
The installation of pipework must be made in accordance with good
plumbing practice, the following points should be considered when installing
pipework.
1. Pipe runs should be chosen to give the shortest most direct route to
the storage cylinder, with minimum bends. Tight bends should be
avoided.
2. The falls of pipes should be arranged to allow the system to be drained
and vented.
Low points, when unavoidable, should be fitted with a drain.
High points, when unavoidable, should be fitted with a vent.
3. Where possible, all pipe runs should have a continuous slight incline
up to the highest point in the system to allow for natural venting of air
from the system.
4. The automatic air vent supplied with the system should be fitted to
the highest point i.e. near the flow connection of the collectors.
5. Adequate support and fixing should be provided for all pipework to
ensure that inclines are maintained and sagging is prevented.
6. Owing to the high temperature differentials within the solar circuit
consideration should be given to the expansion of the pipework, expect
up to 12mm on a 5 metre run. Pipes should be fitted with brackets
and devices that allow for expansion and contraction, rigid fixings
should be avoided.
7. A drain point must be fitted at the lowest point of the solar circuit. It
must be positioned at the down side of the non-return valve to ensure
the system can be fully drained.
All electrical connections must comply with current IEE Regulations.
The Pump is the only electrical connection for the Pump Group. This is
connected to the AST100 Controller’s R1 terminals via the cylinder manual
reset thermostat (thermal overload), refer to wiring diagram in the AST100
Solar Controller instructions.
1. The pump must be connected using 1.0mm² 3 core heat resistant 3
core flex 3093Y marked at least to tolerate 85°.
2. All cable sheath clamps must be correctly fitted.
3. The conductor sheath must be continuous into joint enclosures.
4. Conductors must be correctly fastened to terminals.
5. Conductor insulation to be within 2mm of terminals
6. All cable conductors external to joint enclosures must be insulated
and sheathed.
5.8 ELECTRICAL CONNECTIONS
5.6 SIZING OF PIPES
5.7 PIPEWORK

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5.9 TWO COLLECTOR SCHEMATIC
FIG. 5.9ATWO COLLECTOR FLOW DIAGRAM
Cylinder
1. Collector
2. System Pressure Guage
3. Pump Group
4. Automatic Air Vent
5. Flow Temperature Gauge
6. Shut Off Valve
7. Circulating Pump
8. Flow Limiter
9. Non-Return Valve
10. Pressure Relief Valve (PRV)
11. PRV Discharge Vessel
12. Return Temperature Gauge
13. Air Separator with Manual Air Vent
14. Expansion Vessel
15. Solar AST 100 Controller
16. Upper Cylinder Temperature Sensor (S3)
17. Lower Cylinder Temperature Sensor (S2)
18. Collector Temperature Sensor (S1)
19. System Fill Point (flow)
20. System Fill Point (return)
21. System Drain
22. Cylinder - twin coil shown
23. Boiler (auxiliary heat source)

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5.10 THREE COLLECTOR SCHEMATIC
FIG. 5.10ATHREE COLLECTOR FLOW DIAGRAM
Cylinder
1. Collector
2. System Pressure Guage
3. Pump Group
4. Automatic Air Vent
5. Flow Temperature Gauge
6. Shut Off Valve
7. Circulating Pump
8. Flow Limiter
9. Non-Return Valve
10. Pressure Relief Valve (PRV)
11. PRV Discharge Vessel
12. Return Temperature Gauge
13. Air Separator Manual Air Vent
14. Expansion Vessel
15. Solar AST 100 Controller
16. Upper Cylinder Temperature Sensor (S3)
17. Lower Cylinder Temperature Sensor (S2)
18. Collector Temperature Sensor (S1)
19. System Fill Point (flow)
20. System Fill Point (return)
21. System Drain
22. Cylinder - twin coil shown
23. Boiler (auxiliary heat source)

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FIG. 5.11AMOUNTING PUMP GROUP
5.11 WALL MOUNTING MODULES The pump module is supplied with a wall bracket. The pump group must
be correctly fitted to the wall using the bracket supplied. It should not be
supported by the connecting pipework alone.
FITTING PROCEDURE
1. Determine the best location for the pump group, take into consideration
the following:-
i Access for fill and drain.
ii Position of the expansion vessel.
iii Position of the PR Valve.
iv Provision has to be made for the discharge of the PR Valve
to be collected in a suitable container.
v Ease of plumbing to cylinder and collectors.
2. Mark position for mounting bracket.
3. Drill one holes for wall plug (if used).
4. Screw on bracket to wall and level.
5. Mount pump group onto bracket as shown in fig. 5.11a.
6. Tighten Locknuts
See fig. 5.11A
Bracket Wall Plug
Lock Nut
Lock Nut
Bracket

19
5.12 CONNECTING PIPEWORK
A
B
C
D
A
B
C
D
PR Valve
PR Valve relief
plumbed to low level
Ø15mm
PRV discharge
vessel
Expansion Vessel
System Drain
Automatic Air Vent
Pipes Ø15mm or Ø22mm
see 5.%
FIG. 5.12ACONNECTING PIPEWORK
Shut Off
valve
ReturnFlow