Keston 30C User guide

Installation and Servicing Instructions
FAN POWERED HIGH EFFICIENCY
MODULATING DOMESTIC CONDENSING
GAS COMBINATION BOILER
CE/PI No. 86-CL-38
GC No. 47-930-03
30C
The Keston 30C
These instructions must be left either with the
user or next to the site gas meter.
34 West Common Road
Hayes, Bromley, Kent, BR2 7BX
Tel. [phone] Fax. [phone]
email : [email protected] web : www.keston.co.uk
COMPLIANT WITH BUILDING REGULATION PART L1 & L2
SEDBUK A RATED
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2
Keston 30C - Installation and Servicing
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3 Keston 30C - Installation and Servicing
Relevant Installation changes implemented in this book from Mod Level ............................... A03 (June 2010)
DOCUMENT AMENDMENTS
Keston reserve the right to vary specification without notice
FOR ANY TECHNICAL QUERIES PLESE RING THE KESTON
INSTALLER/TECHNICAL HELPLINE : 0208 462 0262
NOTE. BOILER RESET PROCEDURE -
To reset boiler, turn mode knob to reset position and immediately turn knob back to required setting.
The boiler will repeat the ignition sequence.
NOTES FOR THE INSTALLER
Page 17 - Frame 9, Flue System
• Approved Solvent Weld Waste added
Pae 37 - Frame 38, Wiring Diagram
• Wire removed from flame sensor electrode
Page 73 - Short List of Parts
• Key No. 111 - part number updated
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4
Keston 30C - Installation and Servicing
GENERAL
Keston 30C 30
Gas supply 2H - G20 - 20mbar
Gas Supply Connection 15mm copper compression
Injector Size (mm) 4.65
Inlet Connection Domestic Hot Water 15mm copper compression
Outlet Connection Domestic Hot Water 15mm copper compression
Flow Connection Central Heating 22mm copper compression
Return Connection Central Heating 22mm copper compression
Flue Terminal Diameter mm (in) 50 (nominal)
Average Flue Temp-Mass Flow Rate (DHW) 68oC - 13g/s
Maximum Working Pressure (Sealed Systems) bar (lb/in2) 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) 1.3 (18.9)
Electrical Supply 230 V ~ 50 Hz.
Power Consumption W 152
Fuse Rating External : 3A Internal : T4H HRC L250 V
Water content Central Heating litre (gal) 1.2 (0.26)
Domestic Hot Water litre (gal) 0.5 (0.11)
Packaged Weight kg (lb) 37.8 (83.3)
Maximum Installation Weight kg (lb) 32.8 (72.3)
Boiler Casing Size Height mm (in) 700 (27.5)
Width mm (in) 395 (15.5)
Depth mm (in) 278 (11)
Table 1 - General Data
Note.
Gas consumption is calculated using a
calorific value of 38.7 MJ/m3(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/m3)
b. For ft3/h - divide the gross heat input (Btu/h)
by the gross C.V. of the gas (Btu/ft3)
c. For m
3/h - multiply l/s by 3.6.
Key to symbols
PMS = Maximum operating pressure of water
C13 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.
I2H = An appliance designed for use on 2nd Family gas, Group H only.
* 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.
*Required for maximum flow rate. Boiler operates down to 2 l/min DHW delivery
Maximum DHW Input : 30
Nett CV kW 30.4
(Btu/h) (103,600)
Gross CV kW 33.7
(Btu/h) (115,000)
Gas Consumption l/s 0.871
(ft3/h) (111)
Maximum kW 30.3
DHW Output (Btu/h) (103,300)
DHW Flow Rate l/min 12.4
at 35°C temp. rise. (gpm) (2.8)
DHW Specific Rate l/min 14.5
(gpm) (3.2)
Boiler Input : Max. Min.
Boiler Input ‘Q’ Nett CV kW 24.3 6.1
(Btu/h) (82,900) (20,700)
Gross CV kW 27.0 6.7
(Btu/h) (92,000) (23,000)
Gas Consumption l/s 0.698 0.173
(ft3/h) (89) (22)
Boiler Output :
Non Condensing kW 24.2 6.1
70oC Mean Water temp. (Btu/h) (82,600) (20,700)
Condensing kW 25.6 6.4
40oC Mean Water temp. (Btu/h) (87,400) (21,800)
Seasonal efficiency* (SEDBUK) Band A (91.1%)
NOx Classification CLASS 5
Table 2 - Performance Data - Central Heating Table 3 - Performance Data - Domestic Hot Water
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5 Keston 30C - Installation and Servicing
GENERAL
Boiler size G.C. Appliance No. PI No.
(Benchmark No.)
30 47-930-03 86 CL 38
CONTENTS
Benchmark Commissioning Checklist ..................... 75
Boiler Clearances ......................................................... 9
Boiler Exploded Diagram ....................................... 13,14
Condensate Drain ............................................. 9, 20, 46
Electrical Connections ............................................... 31
Electrical Supply ........................................................... 8
Fault Finding ........................................................... 64-72
Flue Fitting .............................................................. 17, 18
Gas Safety Regulations ................................................ 7
Gas Supply ..................................................................... 8
Installation ............................................................. 15-43
Pump .......................................................................... 59
Safe Handling ................................................................ 6
Servicing ................................................................ 44-63
Short List of Parts ....................................................... 73
Thermostatic Radiator Valves ..................................... 8
Water and Systems .......................................... 8, 10-12
Water Connections ............................................... 28, 29
Water Treatment ......................................................... 12
Wiring Diagram ........................................................... 37
Natural Gas only
Boiler Page
Make and model ....................................................... 5
Appliance serial no. on data badge ....... Front Cover
SEDBUK No. % ......................................................... 4
Controls
Time and temperature control to heating ............. 32
Time and temperature control to hot water .......... 32
Heating zone valves .............................................. n/a
TRV's .........................................................................8
Auto bypass ..............................................................8
Boiler interlock .......................................................... 8
For all boilers
Flushing to BS.7593 .............................................. 12
Inhibitor .................................................................. 12
Central heating mode
Heat input ................................................to be calculated
For assistance see Technical Helpline on the back page
Page
Burner operating pressure .................................... n/a
Central heating flow temp. ...... measure and record
Central heating return temp. ... measure and record
For combination boilers only
Scale reducer ......................................................... 12
Hot water mode
Heat input ..........................................to be calculated
Max. operating burner pressure .............................. n/a
Max. operating water pressure ........... measure & record
Cold water inlet temp ..................... measure & record
Hot water outlet temp. .................... measure & record
Water flow rate at max. setting ............ measure & record
For condensing boilers only
Condensate drain .................................................. 26
For all boilers:
complete, sign & hand over to customer
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
NOTE TO THE INSTALLER: COMPLETE
THE BENCHMARK COMMISSIONING
CHECKLIST AND LEAVE THESE
INSTRUCTIONS WITH APPLIANCE
30C
KESTON 30C
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6
Keston 30C - Installation and Servicing
GENERAL
INTRODUCTION
The Keston 30C boiler is a wall mounted, full sequence,
automatic spark ignition, low water content, fanned flue, high
efficiency, condensing, combination 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
6.1 to 24.2kW (20,700 to 82,600 Btu/h)
Instantaneous domestic hot water (DHW) output is also fully
modulating with a maximum of 30.3kW (103,300 Btu/h)
The boiler is supplied fully assembled with DHW plate heat
exchanger, diverter valve, circulating pump, pressure gauge,
safety valve and CH expansion vessel.
Variable CH and DHW temperature controls are fitted on the
user control and the boiler features a DHW preheat facility.
The boiler includes as standard:
- Automatic bypass
- Boiler frost protection
- Daily pump and diverter valve exercise.
The boiler casing is of white painted mild steel.
The boiler temperature controls are visible located in the
control panel on the front of the boiler.
The heat exchanger is manufactured from cast aluminium.
The boiler is suitable for connection to fully pumped, sealed
heating systems ONLY. Adequate arrangements for completely
draining the system by provision of drain cocks MUST be
provided in the installation pipework.
Pipework from the boiler is routed downwards.
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 calorifier in a heated condition. This
only occurs if pre-heat knob is in the ‘ON’ period.
When there is a demand for CH, the heating system is
supplied at the selected temperature of between 30oC and
80oC, until DHW is drawn off. The full output from the boiler is
then directed via the diverter valve to the plate heat exchanger to
supply a nominal DHW draw-off of 12.4 l/min at 35 oC
temperature rise.
The DHW draw off rate specified above is the nominal that the
boiler flow regulator will give. Due to system variations and
seasonal temperature fluctuations DHW flow rates/temperature
rise will vary, requiring adjustment at the draw off tap.
At low DHW draw-off rate the maximum temperature is limited
to 64 oC by the modulating gas control.
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 personal protective equipment 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.
• 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.
OPTIONAL EXTRA KITS
•Telescopic Concentric Flue B pack
•Electronic Timer (7 day) kit
•RF Electronic Programmable Room Thermostat kit
•Stand Off kit
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7 Keston 30C - Installation and Servicing
GENERAL
SAFETY
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).
BSEN. 12828:2003 Heating Systems in buildings: Design for
water based heating systems.
BSEN 12831:2003 Heating Systems in buildings: Method for
calculation of the design heat load.
BSEN 14336:2004 Heating Systems in buildings: Installation
and commissioning of water based
heating 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 70 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 Keston in writing. If in doubt please enquire.
Any direct connection of a control device not approved by
Keston 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
No asbestos, mercury or CFCs are included in any part of the
boiler or its manufacture.
LOCATION OF BOILER
The boiler must be installed on a flat and vertical internal wall,
capable of adequately supporting the weight of the boiler and
any ancillary equipment.
The boiler may be fitted on a combustible wall and insulation
between the wall 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.
Bathroom Installations
This appliance is rated IP20.
The boiler may be installed in any room or internal space,
although particular attention is drawn to the requirements of the
current IEE (BS.7671) Wiring Regulations and the electrical
provisions of the building regulations applicable in Scotland,
with respect to the installation of the boiler in a room or internal
space containing a bath or shower. For IE reference should be
made to the current ETCI rules for electrical installations and I.S.
813:2002.
If the appliance is to be installed in a room containing a bath or
shower then, providing water jets are not going to be used for
cleaning purposes (as in communal baths/showers), the appliance
must be installed beyond Zone 2, as detailed in BS.7671.
0.6m
Zone 0
Recessed
window
Zone 2
Ceiling
3G8913a
2.25m
Zone 1
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 the wall mounting template and
Frame 1. In addition, sufficient space may be required to
allow lifting access to the wall mounting plate.
• The boiler must be installed on a fire resistant surface.
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8
Keston 30C - 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
Installer to size the gas installation pipework in accordance
with BS6891:2005. Whilst the principle of the 1:1 gas valve
ensures the Keston 30C is able to deliver its 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.
The complete installation MUST be tested for gas tightness
and purged as described in the above code.
WATER CIRCULATION SYSTEM
IMPORTANT.
A minimum length of 1 metre of copper pipe MUST be fitted to
both flow and return connections from the boiler before
connection to any plastic piping.
The central heating system should be in accordance with
BS.6798 and, in addition, for smallbore and microbore
systems, BS.5449.
WATER TREATMENT - see Frame 5
BOILER CONTROL INTERLOCKS
Central heating systems controls should be installed to ensure
the boiler is switched off when there is no demand for heating,
in compliance with Building Regulations.
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.
When thermostatic radiator valves are used, the space heating
temperature control over a living / dining area or hallway having
a heating requirement of at least 10% of the minimum boiler
heat output should be achieved using a room thermostat,
whilst other rooms are individually controlled by thermostatic
radiator valves. However, if the system employs thermostatic
radiator valves on all radiators, or two port valves, then a
bypass circuit must be fitted with an automatic bypass valve to
ensure a flow of water should all valves be in the closed
position.
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 rules for electrical installations.
The mains supply to the boiler and system wiring centre shall
be through one common fused double pole isolator and for
new heating systems, and where practical replacement boiler
installations, the isolator shall be situated adjacent to the
appliance.
CONDENSATE DRAIN
Refer to Frames 15, 25 & 48
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 in accordance with BS 6798.
The drain outlet on the boiler is sized for standard 21.5mm (3/4”)
overflow pipe. It is a universal fitting to allow use of different
brands of pipework.
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9 Keston 30C - Installation and Servicing
GENERAL
1 BOILER DIMENSIONS, SERVICES & CLEARANCES
all dimensions in mm
The boiler connections are made on the boiler connection
tails. Refer to Frames 27-30.
The following minimum clearances must be maintained for
operation and servicing.
Additional space will be required for installation, depending
upon site conditions.
Front clearance
The minimum front clearance when built in to a cupboard is
5mm from the cupboard door but 450mm overall clearance is
still required, with the cupboard door open, to allow for servicing.
*Bottom clearance
Bottom clearance after installation can be reduced to 5mm.
This must be obtained with an easily removable panel, to
enable the consumer to view the system pressure gauge, and to
provide the 100mm clearance required for servicing.
3G10044b
395
30mm
Minimum Top Clearance
100395
400
700
Flue Air
2.5
2.5
from case
*
43 65 57 38
Gas Inlet
39 65
3G10051
Flue
Air
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10
Keston 30C - Installation and Servicing
GENERAL
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 86 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:
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 4 bar.
d. An 8-litre expansion vessel, with an initial charge pressure
of 0.75 bar.
4. 'Make-up' Water. Provision must be made for replacing water
loss from the system, either :
a. From a manually filled 'make-up' vessel with a readily
visible water level. The vessel should be mounted at
least 150mm above the highest point of the system and
be connected through a non-return valve to the system,
fitted at least 150mm below the 'make-up' vessel on the
return side of the radiators.
or
b. Where access to a 'make-up' vessel would be difficult, by
pre-pressurisation of the system.
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 in Table above.
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.
2 SYSTEM REQUIREMENTS - Central Heating
Water Flow Rate and Pressure Loss
Max CH Output kW 24.2
(Btu/h) (82,600)
Water flow rate l/min 17.3
(gal/min) (3.8)
Temperature Differential oC20
(oF) (36)
Head available for m.w.g. 3.4
system (ft.w.g.) (11.1)
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
5. Filling
The system may be filled by the following method:
Where the mains pressure is excessive a pressure
reducing valve must be used to facilitate filling.
a. Thoroughly flush out the whole system with cold
water.
b. Fill and vent the system until the pressure gauge
registers 1bar and examine for leaks. Refer to
Frame 33 for filling detail.
c. Check the operation of the safety valve by raising
the water pressure until the valve lifts. This should
occur within 0.3bar of the preset lift pressure.
d. Release water from the system until the
minimum system design pressure is reached;
1.0 bar if the system is to be pre-pressurised.
continued . . . . . .
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11 Keston 30C - Installation and Servicing
GENERAL
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 8.
Note.
Systems incorporating zone valves which could completely cut off the flow through the system must also include a
bypass.
4 SYSTEM BALANCING
BALANCING
1. Set the programmer 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 the lockshield
valve to give an uninterrupted flow through the radiator.
These valves should now be left as set.
3 SYSTEM REQUIREMENTS - CH (continued) and Hot Water
DOMESTIC HOT WATER
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. In areas of low mains water pressures the
domestic hot water regulator may be removed from the
DHW flow turbine cartridge. Refer to Frame 76. The boiler
will require the flow rate to be set to obtain a temperature
rise of 35oC at the tap furthest from the boiler.
3. The boiler is 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
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.
IMPORTANT
Provision MUST be made to accommodate the expansion of
DHW contained within the appliance, if a non-return valve is
fitted to the DHW inlet, or a water meter with a non-return valve
is installed.
2. Open all manual or thermostatic radiator valves and
adjust the lockshield valves on the remaining radiators,
to give around 20oC temperature drop at each radiator.
3. Adjust the room thermostat and programmer to
NORMAL settings.
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12
Keston 30C - Installation and Servicing
GENERAL
5 WATER TREATMENT
CENTRAL HEATING
The Keston 30C boiler has an ALUMINIUM alloy heat
exchanger.
IMPORTANT.
The application of any other treatment to this product
may render the guarantee of Keston Invalid.
Keston recommend Water Treatment in accordance with
the Benchmark Guidance Notes on Water Treatment in
Central Heating Systems.
If water treatment is used Keston recommend only the use of
FERNOX, MBI or SENTINEL X100 inhibitors and associated water
treatment products, which must be used in accordance with
the manufacturers' instructions.
Notes.
1. It is most important that the correct concentration of the
water treatment products 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
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.
DOMESTIC HOT WATER
In hard water areas where mains 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.
Keston recommend the use of Fernox Quantomat, Sentinel
Combiguard and Calmag CalPhos I scale reducing
devices, which must be used in accordance with the
manufacturers' instructions.
For further information contact:
Fernox Manufacturing Co. Ltd
Cookson Electronics
Forsyth Road
Sheerwater
Woking
Surrey GU21 5RZ
[phone]
Sentinel Performance Solutions
The Heath Business & Technical Park
Runcorn
Cheshire WA7 4QX
Tel: [phone]
www.sentinel-solutions.net
Salamander Engineering Ltd
The Heath Business & Technical Park
Runcorn
Cheshire WA7 4QX
Tel: [phone]
Calmag Ltd.
Unit 4-6, Crown Works
Bradford Road
Sandbeds, Keighley
West Yorkshire BD20 5LN
Tel: [phone]
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13
INSTALLATION
Keston 30C - Installation and Servicing
6 BOILER ASSEMBLY - Exploded View Legend
Note that item numbers are linked to the spares list
104 CH RETURN VALVE
105 CH FLOW VALVE
106 DHW INLET & OUTLET
107 FILLING LOOP
108 PUMP HEAD
110 AIR VENT PUMP
111 DIVERTER VALVE HEAD
112 DIVERTE R VALVE CARTDRIGE
113 PRESSURE RELIEF VALVE
114 PIPE - PRV OUTLET
115 PIPE - FLOW
116 PIPE - RETURN
117 PIPE - EXPANSION VESSEL
118 EXPANSION VESSEL
119 RETURN GROUP MANIFOLD
120 FLOW GROUP MANIFOLD
121 PLATE HEAT EXCHANGER
127 FLOW SENSOR HALL EFFECT
128 FLOW TURBINE CARTRIDGE
131 WATER PRESSURE TRANSDUCER
135 PRESSURE GAUGE
203 GAS COCK
204 PIPE - GAS INLET
205 GAS VALVE
206 PIPE - GAS INJECTOR
211 INJECTOR ASSEMBLY
214 VENTURI
215 FAN
217 BURNER
218 GASKET - BURNER
219 SUMP CLEAN OUT COVER
223 FLUE MANIFOLD
224 FLUE MANIFOLD TOP
227 CLAMP RETAINING FLUE TURRET
228 HOSE CONDENSATE INTERNAL
229 SIPHON TRAP
230 SIPHON TRAP CAP & SEAL
231 CONDENSATE OUTLET CONNECTION
233 FLUE SENSING NIPPLE
301 CONTROLS BOX FIXINGS HINGE & SPRING
302 PRIMARY PCB
303 CUI BOARD
304 CONTROL THERMISTOR (FLOW / RETURN)
306 ELECTRODE IGNITION
307 ELECTRODE DETECTION
308 IGNITER UNIT
309 THERMISTOR NO FLOW
313 IGNITION LEAD
314 CONTROL BOX LENS
324 CONTROLS BOX LID
325 CONTROL BOX FRONT
326 PROGRAMMER INSERT
401 HEAT ENGINE
503 WALL MOUNTING BRACKET
504 FRONT PANEL
505 FASCIA
506 BRACKET - GAS VALVE
507 BRACKET - EXPANSION VESSEL
136 SAFETY VALVE DRAIN PIPE
512 DROP DOWN DOOR
332 FLUE THERMOSTAT
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14
INSTALLATION
Keston 30C - Installation and Servicing
7 BOILER ASSEMBLY - Exploded View (excluding flue box)
BCC
3G9971b
227
224
233 503
313
504
505
512
215
217
309
306
308
211
304
214
206
205
204
223 332
326
325 302
104
110
114
113
136
121
118
507
131
128
127
120
119
117
106
203
106
107
135
105
111
231
112
228
229
303
304
116
115
219
301
401
218
307
230
324
108
314
506
30C
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15
INSTALLATION
Keston 30C - Installation and Servicing
8 UNPACKING
The boiler is supplied fully assembled in Pack 1, together with Pack 2 for flue lengths up to 450mm.
Unpack and check the contents.
Pack 1 Contents
A Boiler
B Hardware Pack Box
C Wall Mounting Plate
D These Installation Instructions
(includes Warranty/Guarantee)
E Wall Mounting Template
(located on internal protective
packaging)
F Turret Clamp
G Safety Valve Drain Pipe
H Weather Compensator
continued . . . . .
C
A
D F
G
H
B
E
E
3G10046a
3G10046a
30C
HARDWARE PACK CONTENTS
Gas Valve Pack
1. Pipe - Gas Inlet
2. Washer - Gas (blue)
3. Gas Cock
Filling Loop Pack
1. 3/8" Fibre washer (x4)
2. Valve (double check valve) fitting
3. Valve - Filling Loop
4. Plastic Chain (x2)
5. Filling Loop
6. 3/8" Blanking Rubber Washer (x2)
Return Valve Pack
1. Pipe CH Return
2. Washer CH
3. Valve Return
DHW Pack
1. Pipe DHW Outlet
2. Valve - Return DHW
3. Washer DHW (x2)
4. Pipe DHW Inlet
5. Nut 1/2"
Accessory Pack
1. Screw (x2)
2. Wallplug (x2)
Flow Valve Pack
1. Pipe CH Flow
2. Washer CH
3. Valve Flow (with gauge)
Gas Valve Pack DHW Pack
Accessory Pack
Flow Valve Pack
Return Valve Pack
Filling Loop
11
1
1
1
5
2
3
3
3
1
23
4
6
5
4
2
2
2
2
3
3
3G9687
INSTALLATION
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16
INSTALLATION
Keston 30C - Installation and Servicing
Pack 2a Contents
1. 3 x elbows
2. 2 x 450mm pipe
3. 3 x 100mm pipe
Pack 2 Contents
2 Boxes
Pack 2b Contents
1. Top Flue Box
2. 6 x screws
3. 2 x Terminals
1
2
3
123
8 UNPACKING....CONT’D
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17
INSTALLATION
Keston 30C - Installation and Servicing
FLUE OUTLET
MAXIMUM LENGTHS
The maximum lengths of both air inlet pipe and flue outlet pipe,
when no bends are used, are as detailed in fig.2b.
However, each bend used has an equivalent length that must be
deducted from the maximum straight length stated in fig. 2b.
Knuckle bends must not be fitted.
A 92.5º swept elbow is equivalent to 1.0m straight length. A 45º
bend is equivalent to 0.5m straight length.
It is possible to have variable flue and air lengths as detailed
below.
Fig. 2b
(does not include allowance for elbow on top of boiler)
Example (assuming 50mm muPVC flue and air pipework)
Air inlet uses two 92.5º swept elbows. Hence, maximum length
permissible (i.e. a+b in fig. 2a) = 22m - 1m - 1m = 20m.
Flue outlet uses one 92.5º swept elbow. Hence, maximum
length permissible (i.e. c+d in fig. 2a)= 22m - 1m = 21m).
But maximum total flue and air intake must not exceed 19m in
the examples above.
Boiler Output Vs Flue Length
Due to the resistance presented by extended flue length a slight
reduction in maximum boiler output will occur where combined
flue and air lengths in excess of 16.0m (50mm muPVC) are
used. In such cases the boiler output will be reduced by 1.0%
per additional metre.
9 FLUE SYSTEM
Note. When installing a replacement boiler a new flue
system must be used. Do not re-use the existing boiler flue
installation.
DESIGN
Individual air supply and flue outlet pipes are used as
standard, although a concentric flue kit is available as an
optional extra.
The material used for flue outlet &/or air inlet must be
muPVC (PVC-C) to BS 5255 and/or BSEN 1566-1 and BSEN
1329 of an internal diameter of 51mm. (i.e. nominal 50mm
diameter muPVC solvent weld waste pipe).
Marley muPVC (PVC-C) Solvent Weld Waste System
(50mm) and Polypipe System 2000 muPVC (PVC-C) solvent
weld waste (50mm) are the only systems approved for this
application.
The following pipes and fittings are approved:
Polypipe System 2000 muPVC solvent Weld Waste System (50mm)
Poly Pipe Code
MU 301 4m length muPVC wastepipe 5/225
MU 313 50mm x 45 deg muPVC obtuse bend
MU 314 50mm x 92.5 deg muPVC swept bend
MU 310 50mm muPVC straigh coupling
MU 316 50mm x 92.5 deg muPVC swept pipe
Marley muPVC solvent Weld Waste System (50mm)
Marley Code
KP 304 50mm x 4m double spigot pipe
KP32 50mm x 45 deg bend
KSC3 50mm straight coupling
KB3 50mm x 88.5 deg bend
KT3 50mm swept tee
Maximum Combined Flue & Air Intake Lengths
Air Inlet 21m
Flue Outlet 21m
Total Flue & Air Intake 22m
Fig.1
FLUE AIR
c a
Flue Box
db
KESTON 30C
3G10025
Fig.2a
When the flue and air terminals are
located within 500mm of each other
ensure that the air terminal is
pointing towards the ground using
a 90º bend and one of the 100mm
sections of pipe provided within
pack 2a.
Both the 50mm flue outlet
terminal and the 50mm air inlet
terminal are supplied with the
twin flue box (pack 2b) and are
illustrated in Fig. 1 and must be
used in ALL installations. (Both
terminals are identical).
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18
INSTALLATION
Keston 30C - Installation and Servicing
FLUE OUTLET
09 FLUE SYSTEM.... CONT’D
SLOPE
‘Horizontal’ flue outlet pipework MUST slope at least 2 degrees
(32mm per metre run) downwards towards the boiler. Pipework
can be vertical. Only swept elbows can be used.
Air inlet pipework can be truly horizontal or vertical, or sloping in
a downward direction towards the boiler but in each case rain,
etc., must be prevented from entering the pipe. There must be
no troughs in any of the pipework, whether it be air inlet or
flue outlet.
Due to the low temperature of the flue gases further
condensate will form within the flue system. Drain points, with
suitable traps, must therefore be incorporated within the flue
system at the base of the vertical flue sections in excess of 6m,
for 50mm muPVC pipe flue systems. These additional
condensate drains must be run to discharge. Such drain points
can be formed using standard muPVC fittings. Refer to fig. 3.
TERMINATIONS
Air inlet terminals must be facing horizontally or downwards to
prevent entry of rain into the terminal and positioned to ensure
only fresh air is drawn into the boiler. The air terminal must be
located outside of the building. Flue terminals must be
positioned so that flue products are not drawn into the air inlet.
Site specific wind conditions should be considered to achieve
this. Drawing of combustion air directly from a ventilated boiler
room invalidates the heat exchanger warranty.
The flue outlet terminal is designed to face outwards and must
not be directed in the region of the air inlet. The flue terminal
and air inlet terminal can be located on different, but not
opposing wall faces.
The two terminals are subject to the requirements of BS 5440
Pt 1 for clearances from features of the building although some
can be decreased to the values indicated.
The Keston 30C, as with any condensing boiler, will generate a
condensate “plume” from the flue terminal in all weather
conditions. Consideration must therefore be given to the effect
of this “plume” when selecting a location for the flue terminal. It
is the responsibility of the installer to ensure the selected
terminal location does not cause nuisance.
If either the air inlet or flue outlet terminate at a height of less
than 2.1m above ground level, the terminal must be protected
by a suitable guard. The K6 terminal guard (with plastic
coating), manufactured by Tower Flue Components Ltd is
suitable for this purpose.
300300L Horizontally from terminal on same wall.
1,5001,500K Vertically from terminal on same wall.
1001,200J From opening in a car port.(not recommended)
1,2001,200I From terminal facing a terminal.
100600H From surface or boundary facing a terminal. *
100300G Above ground or balcony or roof.
50200F From internal or external corner or to a
boundary alongside the terminal. *
5075E From vertical drain or soil pipes.
50200D Below balconies or car port roof (lowest point).
50200C Below eaves.
7575B Below gutters, soil pipes, drain pipes.
50300A Below, above or beside openable window, air
brick, etc.
Air
Inlet
Flue
Terminal
Dimensions (mm)
3G10028a
*The dimensions given in the table above may need to be
increased to avoid wall staining and nuisance depending on
site conditions.
CLEARANCES FROM WALL
Flue outlet and air inlet terminations must be at least 40mm
from the wall face.
DISTANCE BETWEEN FLUE OUTLET & AIR
INLET
There is no maximum - the terminations must not be on
opposite sides of the dwelling but can be in areas of unequal
pressure.
A minimum clearance of at least 500mm must be left between
the terminations otherwise a 90º elbow MUST be fitted to air
inlet and pointed towards the ground. The absolute minimum
clearance between the flue and air terminals is 100mm.
GENERAL INSTALLATIONS
All parts of the system must be constructed in accordance with
BS 5440 Part 1, except where specifically mentioned in these
instructions.
All pipework must be adequately supported.
All joints other than approved push-on or plastic compression
connectors must be made and sealed with solvent cement
suitable for muPVC pipes and conforming to BS 6209: 1982.
Consideration must be given to Corgi/Gas Safe bulletin TB200/
TB008 regarding flues in voids.
The boiler casing must always be correctly fitted to the boiler
when leaving the appliance operational.
External wall faces and any internal faces of cavity walls must
be good.
Rubber collars are available for flue and air terminals to finish
the external wall face around the terminals (Part No
C.08.00.07.0).
AIR SUPPLY
The Keston 30C is a room sealed appliance and therefore
does not require purpose provided ventilation to the boiler room
for combustion air.
COMPARTMENT INSTALLATION
Due to the low casing temperatures generated by the boiler, no
compartment ventilation is required. However, the cupboard or
compartment must not be used for storage.
6 in min.
Tee Fitting
To Boiler
To Terminal
Fig.3
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19
INSTALLATION
Keston 30C - Installation and Servicing
10 INSTALLING THE BOILER
Installation of the boiler is straightforward but consideration must be given to access to allow flue and air pipes to be pushed
through walls and ceilings. The order in which the components are installed will depend upon particular site conditions, but in
general it will be easiest and most accurate to install the boiler and then build up the flue outlet and air inlet pipes to the terminal
- this is the sequence described.
The wall mounting template is located on the internal
protective packaging.
Note.
The template shows the positions of the fixing holes and
the position that the twin flue box is located. Care MUST
be taken to ensure the correct holes are drilled.
1. Tape template into the selected position. Ensure
squareness by hanging a plumbline as shown.
2. Mark onto the wall the following:
aThe wall mounting plate screw positions (choose one
from each group).
bThe position of the air and flue when exiting straight out
of the wall where the boiler is mounted.
Note.
Mark the centre of the hole as well as the
circumference.
3. Remove the template from the wall.
11 WALL MOUNTING TEMPLATE
3G10056
12 PREPARING THE WALL
IMPORTANT.
Ensure that, during the cutting operation, masonry falling
outside of the building does not cause damage or personal
injury.
1. Cut the flue and air holes (preferably with 60mm core
bore tool) ensuring the holes are square to the wall.
2. Drill 2 holes with a 7.5mm / 8mm masonry drill and
insert the plastic plugs, provided, for the wall mounting
plate.
3. Locate 2 No.14 x 50mm screws in the wall mounting
plate (one at each side, in any of the 3 holes provided at
each side) and screw home.
3G10030
X
Section
through wall
Note. Check all of the hole
positions before drilling.
Rear flue only
60mm diameter
holes
INSTALLATION
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20
INSTALLATION
Keston 30C - Installation and Servicing
15 CONDENSATE DRAIN
Ensure that the siphon is full of water before
commissioning the boiler. Refer to Frame 26.
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.
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 and is suitable for either push fit or
solvent weld applications. This size must not be
reduced in any part of its length.
The boiler includes as standard, a 75mm condensate
trap. The condensate trap also includes a siphon to
reduce the possibility of freezing in the drain outlet.
If external condensate pipe is used then the pipe
should be 32mm nominal diameter. Consideration
should be given to insulating external condensate pipe
runs.
esp9496
Example of fixing
14 MOUNTING THE BOILER
1. Ensure the plastic plugs are removed from both the CH
and DHW connections before mounting the boiler.
2. Lift the boiler onto the wall mounting plate (refer to the
Introduction section for safe handling advice), locating it
over the two tabs.
3G9974
30C
13 FITTING THE WALL MOUNTING PLATE
Screw the wall mounting plate to the wall using 2 wall plugs
(previously fitted) with the 2 screws provided.
Choose one of the 2 sets of slots in left and right bank.
Ensuring that at least one of the screws is fitted into a top
slot.
INSTALLATION
205531-3.pmd 01/07/2010, 10:2420