Thermaflow TH6-210U M3 Operating manual

ELECTRIC COMBINATION BOILER
(European Patent No: 1757678. Design Right Protected).
TH6-210U M3
This product is suitable for connection to ~230-240V, 50Hz
INSTRUCTIONS FOR USE, INSTALLATION AND
SERVICING for all models with serial No beginning 5-
TO BE LEFT WITH THE USER
The instructions consist of three parts; User, Installation and Servicing instructions, which include the guarantee registration
card.
The instructions are an integral part of the appliance and must, to comply with the current issue of the building, electrical
regulations and water by-laws, be handed to the user on completion of the installation.
GUARANTEE REGISTRATION
Thank you for installing a new Thermaflow product in your home.
Thermaflow Ltd appliances, are manufactured to the very highest standards so we are pleased to offer our customers, a
comprehensive first year guarantee and a second year parts guarantee.
In the instruction envelope is to be found your guarantee registration card, which must be completed and returned to
Thermaflow Ltd or register your Thermaflow appliance for 1st year guarantee protection by calling the below number.
Our guarantee gives you peace of mind valuable protection against breakdown by covering the cost of-
•All replacement parts
•All labour charges
•All call-out charges
THERMAFLOW LTD
Nethercroy Road, Croy, Kilsyth, Glasgow, G65 9JF
Customer services
Tel [phone]
email [e-mail]
Web www.thermaflowheating.co.uk
Issue Number: 2a Issue date: February 2012
Copyright Notice
This document contains proprietary information protected by copyright, and this Manual and documentation are copyrighted. All rights are reserved. No part of this
document may be photocopied or reproduced by mechanical, electronic, or other means in any form without permission from Thermaflow Ltd.
©Copyright Thermaflow Ltd 2006-12 -All rights reserved.

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PART1 –INSTRUCTIONS FOR USE
1.1 INTRODUCTION
This appliance can be used by children aged from 8 years and above and persons with
reduced physical, sensory or mental capabilities or lack of experience and knowledge if
they have been given supervision or instruction concerning the use of the appliance in a
safe way and understand the hazards involved. Children shall not play with the appliance.
Cleaning and user maintenance shall not be made by children without supervision
Please read these Instructions and follow them carefully for the safe and economical use
of your combination boiler.
This boiler must have been installed by a competent person in accordance with the
current rules in force in the countries of destination at the time of installation.
The boiler is automatic in operation once the external controls are set e.g. time clock or
programmable room thermostat.
IMPORTANT NOTICE
1.2 Domestic hot water temperature
Hot water is NOT user adjustable and is pre-set to 50ºC at the thermostatic mixing valve fitted
on the hot water outlet at the top left of the boiler. It is TMV3 rated for Anti Scald purposes.
The combination boiler is able to provide room heating as part of an under-floor or central
heating system and domestic hot water direct from the cold water supply, without the need for
secondary storage.
1.3 To turn the boiler off
To turn the boiler off, isolate the boiler from both the electrical supplies i.e. the 24hr supply and
the interrupted supply, both isolating switches should be positioned next to the boiler.
1.4 Maintenance and servicing
To ensure the continued efficient and safe operation of the appliance it is recommended
that it is checked and serviced as necessary at regular intervals. The frequency of
servicing will depend upon the particular installation conditions and usage, but in general
once a year should be enough.
Servicing & maintenance should be carried out by a competent person in accordance with the
rules in force in the countries of destination.
To obtain service please call your installer or Thermaflow Ltd, using the telephone number on
the appliance or at the front of this manual.
Please be advised that the Thermaflow log book should be completed by the installation
engineer on completion of commission and servicing.
1.5 Clearances
The boiler requires a clearance in front and at the sides for safety, servicing and maintenance
access, see diagram 2.2.3 for the requirements.

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1.6 Draining and filling
Caution this boiler works in a pressurised system which must only be drained, refilled and pressurised by
a person competent to do so.
Note: if the pressure gauge indicates a loss of pressure that is less than 60 KPA (0.9 bar),
YOU MUST CONTACT YOUR INSTALLER unless you have been instructed by your installer on how to
re-pressurise the system correctly.
1.7 Replacement parts
If replacements parts are required, contact your Installer, Service Company or Thermalflow Ltd. Please
quote the name and model of your appliance. (Ref. Spare Parts List - section 1.8.1).
It is recommended that the Thermaflow has a safety and maintenance check on an annual
basis.
A pressure reducing valve must be fitted to the cold water inlet of the appliance if the
incoming pressure exceeds 300kPA (3 Bar).
The position of the outlet from the discharge pipe shall be visible to the occupants and
shall be positioned away from any electrical devices.
The position of discharge pipes, (Tundish), drain valves and motorised valves etc, must
be positioned away from electrical components.
The water may drip from the discharge pipe of the pressure-relief device and must be left
open to the atmosphere.
The pressure relief device must be operated regularly to remove lime deposits and to
verify that it is not blocked.
The discharge pipe connected to the pressure-relief device must be installed in a
continuously downward direction and in a frost free environment.
DANGER: Failure to operate the relief valve easing gear at least every six months may
result in the water heater exploding. Continuous leakage of water from the valve may
indicate a problem with the water heater
IMPORTANT: If any external heat sources are being connected to the water heater, they
must be connected as detailed in this instruction manual. There must be temperature
control thermostats fitted to control each heat source and must be set to a maximum
temperature of 80⁰C
(Additional Information given in G3 of the building regulations for discharge pipes)

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Contents
PART1 –INSTRUCTIONS FOR USE...................................................................2
1.1INTRODUCTION.......................................................................................2
1.2 Domestic hot water temperature............................................................2
1.3 To turn the boiler off ...............................................................................2
1.4 Maintenance and servicing.....................................................................2
1.5 Clearances...............................................................................................2
1.6 Draining and filling..................................................................................3
1.7 Replacement parts ..................................................................................3
0.1 Instructions General................................................................................6
0.2 Draining & Filling.....................................................................................7
0.3 Manual Handling Guidance.....................................................................7
0.4 TESTING & CERTIFICATION...................................................................7
0.5 THE UNIT LOCATION..............................................................................7
0.6 Water Connections..................................................................................8
1.8 Thermaflow TH Model MK2..........................Error! Bookmark not defined.
TABLE 1.8.1 [DATA]..........................................................................................10
Part 2 –INSTALLATION........................................................................................11
2.1.1 Sheet metal parts.....................................................................................11
2.1.2 Statutory requirements............................................................................11
2.1.3 DATA 11
2.1.4 ELECTRICAL SUPPLY.............................................................................11
2.1.5 Electrical supply.......................................................................................12
2.1.6 Heating system controls..........................................................................12
2.2.1 Boiler Position..........................................................................................12
2.2.2 Boilers in a compartment ........................................................................13
2.2.3 Clearances allow for external primary heat transfer kit ........................14
2.3.1 General notes...........................................................................................14
2.3.2 Safety valve..............................................................................................14
2.3.3 Pressure & Temperature Gauge..............................................................14
2.3.4 Pump 14
2.3.5 Expansion vessel.....................................................................................14
2.3.6 By- pass....................................................................................................14
2.3.7 Filling sealed systems.............................................................................14
2.3.8 Corrosion inhibitor...................................................................................14
2.3.9 Draining ....................................................................................................15
2.4. Domestic hot water system.......................................................................15
2.4.1 General 15
2.4.2 Water pressure.........................................................................................15
2.4.3 HOT WATER FLOW RATE .......................................................................15
2.4.4 Hard water areas......................................................................................15
2.5. Installation, PREPARATION [water connections]....................................15
2.5.1 Water connections................................................................................15
2.5.2 SAFETY VALVE DISCHARGE.............................................................16
2.6 ELECTRICAL INSTALLATION REQUIREMENTS.......................................16
IMPORTANT 16
2.6.1 ELECTRICAL SUPPLY.............................................................................17
2.6.2b OFF-PEAK & 24 HR WIRING CIRCUITS................................................18
2.6.3 External Controls..................................................................................20
ELECTRICAL CONNECTIONS.....................................................................20
2.6.4 Supply cable connection [24 HR Supply]..............................................20
2.6.5 Heating system controls........................................................................20

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2.6.6 Electrical Test.......................................................................................21
2.6.7 Supply cable connection [Interrupted off peak supply]..........................21
2.6.8 Electrical Test.......................................................................................21
2.6.9 IMPORTANT: Electricity tariffs..............................................................21
2.7 Commissioning...........................................................................................22
2.7.1 Filling domestic water circuit.................................................................22
2.7.2 Filling the heating system .....................................................................22
2.7.3 Domestic hot water flow rate.................................................................22
2.7.4 Temperature settings............................................................................22
2.7.5 Heating system commissioning.............................................................23
2.7.6 Completion...........................................................................................23
2.7.7 INSTRUCT THE USER..............................................................................23
Part 3 - SERVICING...............................................................................................24
3.1. Fault Finding ..............................................................................................24
3.1.1 Fault: No domestic hot water or central heating....................................25
3.1.2 Fault: No central heating, but hot water at taps.....................................26
3.1.3 Fault: CENTRAL HEATING BUT No hot water at taps..........................27
3.2 MAINTENANCE ......................................................................................30
Checking the pressure in the expansion vessel.............................................30
3.2.3 Checking the inline strainer...................................................................30
3.2.4 Checking the hot water blending valve..................................................30
3.2.5 Checking the concentration of corrosion inhibitor..................................31
3.2.6 Preventing pump seizure in summer.....................................................31
3.2.7Checking correct operation of electrical components.............................31
3.2.8 Low pressure switch.............................................................................31
3.2.9 Control and high limit manual re-set thermostats..................................31
3.2.12 Checking the heating elements...........................................................32
3.2.13 Checking circuit breakers....................................................................32
3.2.14 Checking the contactor.......................................................................32
3.2.15 Check the operation of the AQUA STAT.............................................32
IMPORTANT PRE-INSTALLATION NOTES
•Power supply and wiring
The power supply to the premises must meet the minimum requirements of the unit being
installed, with special attention given to the supply current, cable size and MCB recommendation.
The supply voltage to the appliance must never drop below 207 Volts.
Important
The electrical supply requirements:-
The 6 KW boiler meets the requirements of EN 61000-3-11
The equipment is intended for use only in premises having a service current capacity of ≥ 100A
per phase , supplied from a distribution network having a nominal voltage of 400/230 V, and the
user should consult the supply authority if necessary to determine if the service current capacity
at the interface point is sufficient for the equipment.

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0.1 Instructions General
A pressure reducing valve must be fitted to the cold water inlet if the incoming water pressure exceeds
300 KPA (3.0 Bar).
The primary operating pressure initial charge is 120 KPA (1.2 bar) this will increase to around 200 KPA
(2.0Bar) when the system has reached maximum temperature and will depend on system volume.
The primary expansion is internal and is formed when the vessel is initially filled. It has a volume of 18.5L
for the 210, 23L for the 250 and 28L for the 330 model.
The secondary expansion vessel pre-charge pressure is between 200-350 KPA (2-3.5 bar) and has a
volume of 0.5 litres.
The primary pressure relief valve is set to 300 KPA (3.0 Bar).
Thermaflow Model Number
TH6-210U M3
Primary storage capacity
200 Litres
Weight when Empty
70KG
Weight when Full
278KG
WARNING: BEFORE OBTAINING ACCESS TO TERMINALS, ALL SUPPLY CIRCUITS MUST
BE DISCONNECTED.
The TH6has 2heating elements fitted. Size 16” in length and are manufactured from Inc-alloy
EN60335.2.73.
The rated power input of the TH6 appliance is ~230- 240V, 50Hz, 5400-6000w
The elements fitted to the Thermaflow should NOT be replaced with elements which are not
approved for the Thermaflow boiler.

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0.2 Draining & Filling
CAUTION: THE THERMAFLOW BOILER WORKS IN A PRESSURISED SYSTEM WHICH MUST
ONLY BE DRAINED, REFILLED AND PRESSURISED BY A COMPETENT PERSON.
There is a drain tap fitted to the Thermaflow boiler to drain the primary circuit within the boiler it is located
at the bottom of the appliance.
Further drain taps should be fitted into the pipe-work at the lowest point of the potable water circuit and
the heating circuit and should terminate outside the dwelling in a suitable position.
0.3 Manual Handling Guidance
During the appliance installation it will be necessary to employ caution and assistance whilst
lifting as the appliance exceeds the recommended weight for a one man lift.
DO NOT LIFT THE APPLIANCE BY ATTACHED PIPE-WORK OR COMPONENTS
In certain situations it may be required to use a mechanical handling aid.
Take care to avoid trip hazards, slippery or wet surfaces.
IMPORTANT INFORMATION
0.4 TESTING & CERTIFICATION
The boiler is tested and certified for safety and performance. It is therefore important that no alteration is
made to the boiler, without permission, in writing, from Thermaflow Ltd.
Any alteration not approved by Thermaflow Ltd, could invalidate the certification, boiler warranty and may
also infringe the current issue of the statutory requirements, see section 2.1.2
The unit should be stored in a dry environment and should be handled with care to prevent attached
components being damaged or connections becoming loose. All connections should be checked for
leaks after installation.
0.5 THE UNIT LOCATION
The unit should be preferably located in a cupboard with a minimum dimension of;
W 675mm x D. 740mm x H. 2.4M
The floor to which the unit is placed upon should be capable of withstanding a load of:
278KG
The unit should be positioned in a manner that allows access to all components for future
maintenance.
If located in a cupboard the unit should be positioned with all components facing the entrance to
allow elements to be replaced if required or any of the other components.

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0.6 Water Connections
There are six water connections to be made when installing the Thermaflow.
They are as follows:
1) Flow and return connections to the heating system are 22mm compression.
2) Cold water inlet-22mm compression.
3) Hot water outlet -22mm compression.
4) Pressure relief valve- 15mm compression.
5) The pressure relief valve connection should be used for no other purpose.
6) The heating expansion vessel- 22mm compression.

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1 c
1a
11
2
3
4a
4b
1b
17a
a
13a
18
19
14
13b
16
17b
20
10,10a
10b
8
7
6
21
12
5
15
9
Unit Design (Protected by Design Rights)

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TABLE 1.8.1 [DATA]
TH6-210U M3
Lift Weight empty
70KG
Total Weight boxed
80KG
Weight Full
278KG
Heating Flow & Return
22mm Compression or push fit
Domestic Cold Water Inlet
22mm Compression
Domestic Hot Water Outlet
22mm Compression
Safety Relief Valve
PRESET 300 KPA (3.0 Bar)
Safety Relief Valve Discharge
15mm Compression
Water Content Primary
200
Water Content Domestic (Secondary)
2 Litres / 0.44 Gallons
Primary Expansion INTERNAL
22 Litres / 4.9 Gallons. 28 Litres 6.3 Gallons
Secondary Expansion Vessel
0.5 Litres/0.11 Gallons
CH Cold Fill Pressure Min/Max
90 KPA (0.9 Bar) minimum / 120 KPA (1.2 Bar) maximum
D.H.W Working Pressure
20 –300 KPA (0.2-3.0 Bar)
Max. CH system Content (Excluding unit volume)
100Litres
Electrical Mains Supply
~230-240V, 50Hz
Electrical Rating (Interrupted) & Supply Current
TH6/ 5400-6000w –25 amp
MCB Rating (amp)
6Kw (26amp) 32 A TYPE B MCB
Electrical Rating (24Hr) Control Circuit
95w, Fused 3amp or 6A Type B MCB

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PART 2 –INSTALLATION
2.1.1 Sheet metal parts
Warning: when installing or servicing this boiler care should be taken when handling the edges of metal
parts to avoid any possibility of personal injury.
2.1.2 Statutory requirements
The installation of this boiler must be carried out by a competent person in accordance with the current
rules in force in the countries of destination at the time of installation, and in accordance with the relevant
requirements of the current issue of:
The Building Regulations
The Local Water Company bye-laws
The Building Standards Regulations (Scotland)
The Health and Safety at Work Act
Manufacturer’s instructions, supplied
Manufacturer’s instructions must not be taken as overriding statutory requirements.
2.1.3 DATA
The data label is on the front case of the boiler.
2.1.4 ELECTRICAL SUPPLY
•Power supply and wiring
The power supply to the premises must meet the minimum requirements of the unit being installed, with
special attention given to the supply current, cable size and MCB recommendation. The supply voltage to
the appliance must never drop below 207 Volts.
Important:
The electrical supply requirements:-
The 9 KW and 12 KW boilers meet the requirements of EN 61000-3-11
The 12 KW boilers must be installed in premises having a service supply of ≥ 100A
per phase.
WARNING: This boiler must be earthed
WARNING: Means for disconnection must be incorporated in the fixed wiring in accordance
with the wiring rules
WARNING: Electrical work must be carried out by a person competent to do so
All system components shall be of an approved type.
The electrical installation shall be in accordance with the current rules in force in the countries of
destination at the time of installation.

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2.1.5 Electrical supply
Means of disconnection of the electrical supply to the boiler must be incorporated in the fixed
wiring in accordance with the wiring rules.
Two isolators are required at the boiler when using an interrupted off peak supply eg. E2000, one
for the 24hr supply, and the other for the interrupted supply (off peak if available).
If using Scottish & Southern Energy, only one isolator is required at the boiler.
Means of disconnection of the 24hr supply should be by a double pole switched fused spur (fuse rating
3 amp), having a minimum contact separation of 3mm in each pole. The fused spur should be readily
accessible and adjacent to the appliance. It should be identified as to its use.
Means of disconnection should not be fitted in a room containing a fixed bath or shower. The 24hr
mains supply cable and other cables for external controls must be heat resistant and flexible PVC type of
at least 0.75mm2 (24/ 0.20mm)
Means of disconnection of the interrupted supply (off peak) should be by a double pole switched
(63amp isolator with a 32 amp MCB Type B for the TH6/ model), having a minimum contact separation of
3mm in each pole. The switched isolator and MCB should be readily accessible and installed at the origin
of the supply to the boiler. It should be identified as to its use.
Means of disconnection should be readily accessible and adjacent to the appliance. It should be
identified as to its use.
The interrupted mains supply cable must have a cross sectional area of at least (6mm² for the
TH6/ model). The mains supply cable at the boiler location should be preferably encased by
flexible conduit.
2.1.6 Heating system controls
The heating system should have installed: A timer and room thermostat or a programmable room
thermostat controlling the central heating system or under-floor heating.
If an under-floor heating system is being installed it must have its own pump and blending valve.
Thermostatic radiator valves should be installed in addition to the room thermostat for better economy
and energy saving.
2.2.1 Boiler Position
The boiler must be installed in accordance with the rules in force in the countries of destination. This
boiler is not suitable for fitting outside.
Any electrical switch must be positioned so that it cannot be touched by a person using a bath or
shower.
The boiler must be positioned on a level base or floor which is sufficiently robust to take its weight, (Refer
to table 1, “Data”)
If the location of the boiler or any part of the system is subject to severe cold weather conditions, it is
recommended that a frost thermostat is fitted. Any part of the system that may be vulnerable to freezing
must be protected.

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2.2.2 Boilers in a compartment
Where the installation of the boiler will be in an unusual position, the current issue of BS 6798 gives
detailed guidance on these requirements.
An existing cupboard or compartment modified for the purpose may be used, providing minimum
clearances are maintained. Details of essential requirements for cupboards or compartment design are
given in the current issue of BS6798.
The doorway opening should be of sufficient size to allow for easy removal of the boiler.
Where the boiler is fitted in a cupboard or compartment, permanent ventilation is not necessarily required
and will depend on compartment size and airflow around the boiler.
Compartment ventilation is required to dissipate heat from any external heating circuit pipe-work,
to prevent overheating of the electrical components and wiring.
Any existing compartment air vents must not be removed or blocked off.

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2.2.3 Clearances allow for external primary heat transfer kit
The boiler should be positioned so that at least the minimum
operational and servicing clearances are provided, see diagram
2.2.3 additional clearances may be required around the boiler for
installation. A clearance of 600mm is required at the front of the
boiler for maintenance and installation.
2.3.1 General notes
The boiler is intended for use in a sealed system only.
2.3.2 Safety valve
The safety relief valve is an integral part of the boiler. It cannot
be adjusted but has a manual test device.
2.3.3 Pressure & Temperature Gauge
A pressure and temperature gauge is incorporated into the boiler to indicate the system pressure and
temperature. The gauge has a cold fill set pointer.
2.3.4 Pump
The circulation pump is integral with the boiler.
2.3.5 Expansion vessel
The 210L has 22 litres of internal expansion and If the water content of the
heating system exceeds the maximum quoted in table 1, [Data] an additional
expansion vessel should be connected into the system as close as possible
to the central heating return connection of the boiler. Ref. Diagram 2.3.5
The charge pressure shall not be less than the static head at the point of
connection, which is the height of the top point of the system above the
expansion vessel.
2.3.6 By- pass
An automatic by- pass valve should be incorporated in the system for maximum system
efficiency. (A By-Pass MUST be fitted to the system by the installer).
2.3.7 Filling sealed systems
The boiler has a filling loop incorporated within it, and pressure gauge to register the fill pressure.
There must be no permanent connection to the mains water supply; even though a non-return valve is
supplied. Disconnect filling loop and seal both valves with suitable caps.
2.3.8 Corrosion inhibitor
The maintenance of sufficient concentration of corrosion inhibitor in your Thermaflow system is vital to
prevent corrosion. We would recommend sentinel X100, or equivalent. Dose appropriately according to
the size of the Thermaflow boiler and central heating system volume combined.
Thermaflow ®
Expansion
Vessel
Diagram 2.3.5
front
675mm
740mm
Diagram 2.2.3 - Clearances
Thermaflow
Unit
600mm

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2.3.9 Draining
A draining tap must be provided at the lowest points of the system, which will allow the entire
system to be drained.
The boiler has a drain tap fitted for draining of the primary circuit.
2.4. Domestic hot water system
2.4.1 General
The domestic hot water service must be in accordance with the rules in force in the countries of
destination.
2.4.2 Water pressure
For the minimum and maximum, working pressures of the domestic hot water circuit of the boiler refer to
(“data” table 1).
If the cold water inlet pressure exceeds 300 KPA (3 bar) a pressure reducing valve must be fitted
to the inlet to the boiler.
2.4.3 HOT WATER FLOW RATE
The boiler is capable of flow rates of 14-16 litres per/min @ 35ºC ∆t (depending on model). Hot water
flow rate and pressure will be determined by the volume and pressure of the incoming cold water supply
and the primary store temperature.
2.4.4 Hard water areas
In areas where the water is “Hard” more than 200 mg / litre, it is recommended that a proprietary
scale reducer or water softener is fitted in the cold water supply to the boiler depending on what
is necessary to prevent lime scale build up in the heat exchangers, pipe-work or valves.
Consult the local water authority for additional advice.
A double check valve assembly must be fitted upstream of the scale reducer or water softener.
For the relative position of the scale reducer or water softener and pressure reducing valve if
required, refer to the Manufacturer’s instructions.
2.5. Installation, PREPARATION [water connections]
2.5.1 Water connections
See General Data Diagram 1.8.1 & table 1.8.1 for pipe work connections
It is recommended to flush out the domestic water and heating system before connecting to the
boiler.
While making the connections, do not subject any of the connections to heat as you may damage
the seals.

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2.5.2 SAFETY VALVE DISCHARGE
It must not discharge above an entrance or window or any type of public access.
The position of the discharge outlet shall be visible to the occupants and shall be positioned
away from any electrical devices.
The position of discharge pipes (Tundish) drain valves and motorised valves etc must be
positioned away from electrical components.
The water may drip from the discharge pipe of the pressure-relief device and must be left open to
the atmosphere.
The pressure relief device must be operated regularly to remove lime deposits and to verify that it
is not blocked.
The discharge pipe connected to the pressure-relief device must be installed in a continuously
downward direction and in a frost free environment.
The connection for the discharge is made at the bottom side of the safety relief valve.
This must be extended from the safety relief valve with not less than 15mm O.D. metal pipe, to
discharge, in a visible position, outside the building, facing downwards, preferably over a drain.
The pipe must have a continuous fall and be routed to a position so that discharge water,
possibly boiling or steam, cannot create any danger to persons, damage to property or external
electrical components and wiring.
2.6 ELECTRICAL INSTALLATION REQUIREMENTS
•Power supply and wiring
The power supply to the premises must meet the minimum requirements of the unit being installed, with
special attention given to the supply current, cable size and MCB recommendation. The supply voltage to
the appliance must never drop below 207 Volts.
IMPORTANT
THE ELECTRICAL SUPPLY REQUIREMENTS:-
The 6 KW boiler meets the requirements of EN 61000-3-11
The 6 KW boiler must be installed in premises having a service supply of ≥ 100A
per phase.

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2.6.1 ELECTRICAL SUPPLY
IMPORTANT
If the boiler is wired to the Scottish Power Domestic & Economy 200 tariff, it requires two separate ~230-
240V power supplies. A (24HR) supply for controls and an interruptible supply for the boiler. (Off Peak
power supply if it is available).
The off peak or interruptible mains supply is wired according to the following diagram 2.6.1, from the 63
amp double pole isolator by way of flexible 10mm² cable into the main terminals in enclosure marked No.
16 on the boiler schematic on page 9 of this instruction manual, see diagram 2.6.1b on page 18.
If the boiler is wired to a 24 hour tariff or Economy 10 tariff for wet electric central heating then a separate
3 amp supply is not required for the controls as the controls are supplied via the 6 amp MCB in the
control box marked No.16 on the boiler schematic on page 9 of this instruction manual, see diagram
2.6.1b on page 18.
A Local isolator may also be required at the boiler position.
diagram 2.6.1
CABLE SIZING
Boiler rating minimum Cable Size ~230-240V-50Hz, TH6/ 5400-6000w –25 amp –10mm²
MCB MUST BE TYPE B.
2.6.2
The mains supply into the boiler shown in the diagram on page 9, should be wired to the 24HR supply via
3 Amp fused isolating switch located at the boiler, ref. diagram 2.6.2b.
L
N
E
L
N
E
Supply
*
*
*
100A Double Pole
Isolating switch located in the
Thermaflow boiler control box
*25mm2COLOUR CODED METER TAILS
CONNECT TO METER / TELE-SWITCH
100A Double Pole
Isolating switch
With 40A or 63A Type B
MCB located at meter or
consumer unit
100A Double Pole
local Isolating switch
located at the Thermaflow
boiler position

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2.6.2b OFF-PEAK & 24 HR WIRING CIRCUITS
E
E
N
N
L
100A
ISOLATOR
6A
MCB
E1
16A
E2
16A
E3
16A
E4
16A
A1
1
E4
E3
E2
E1
~240VAC
SUPPLY
HEATING ELEMENTS
E3 not used on 9KW
models
N
1
2
4
3
13
5
11
16
14
12
15
10
9
8
7
6
17
C
N/C
N/O
C
L
N/C
C
N/C
C
2
1
HWP
C
N/O
CHP
C
3
4
C
C
2
2
1
1
C
IF E10 –Supply to
controls comes from
6A MCB in top control
box
IF Scottish Power
E2000 tariff –
External 3AMP 24hr
supply must be
taken to supply
controls as shown
NO NEUTRAL OR
EARTHS SHOWN FOR
CLARITY
Requires ~240v –3AMP
Supply when using
Scottish Power Domestic &
Economy 2000 tariff
LINK REMOVED
if E2000 Tariff
LOW PRESSURE SWITCH
1stDSTAGE HIGH LIMIT CUT
OUT MANUAL RESET
2nd STAGE HIGH LIMIT CUT
OUT MANUAL RESET
TAMPER PROOF CONTROL
THERMOSTAT SET TO 25°C
REMOVE LINKS AND FIT OFF PEAK CONTROL IF
E10 OR EXTERNAL PRIMARY HEAT SOURCES ARE
BEING LINKED TO THERMAFLOW BOILER
Programmable
Room
Thermostat
Ie. Danfoss
TP5000si or
equivalent
CONTROLS
ONLY
.
A
B
A1
A1
A2
14
11
A2
11
14
18
NEUTRAL SHOWN AS
DOTTED & SOLID
LINE SHOWS TWO
SEPARATE CIRCUITS
CONTROL STAT ON
E1 & E4
A2
2
A2
A1
4
4
1
3
2
A1
A2
3
1
2

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2.6.2c OFF-PEAK TIMER & WIRING CIRCUIT
The summer channel controls the
timing of the top element on a 6kw
Thermaflow boiler via contactor.
The winter channel controls the
timing of the bottom element on all
Thermaflow boiler models via
contactor 1 on the Thermaflow
boiler
Connections onto
main wiring terminal
on boiler.
The Off Peak Control allows you to time the boiler to charge during the
reduced rate periods on wet electric central heating tariffs
Off Peak Timer
required when using
E10 wet electric tariff
or similar
OFF PEAK TIMER
All Connections are
~240V AC
IMPORTANT
Use the piece of 5 core heat
resistant flex supplied with the
programmer.
The control allows you
to reduce running
costs substantially.
N
N
L
E
1
3
10
2
4
12
11
Off Peak Timer

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2.6.3 External Controls
External heating controls should be connected to the appropriate terminals numbered in diagram 2.6.2b.
WARNING: ALL EXTERNAL CONTROLS MUST NOT BE TAKEN FROM ANY OTHER POWER
SUPPLY OTHER THAN VIA THE
3 AMP FUSED ISOLATING SWITCH MENTIONED ABOVE.
ELECTRICAL CONNECTIONS
2.6.4 Supply cable connection [24 HR Supply]
Caution: To prevent an induced current from switching the central heating on when not required it is
important that the heating system control cables are separated from the other mains cables.
There is provided 1 or 2 heat resistant cables extending from the main panel situated between
both circulating pumps depending on the tariff being used. One cable has 3 cores. Live, Neutral
and earth to be connected to a 3 amp double pole fused isolator.
The other cable has 2 cores coloured brown and (blue core covered with brown sleeve) these are
both common live and switched live wires to be connected to external heating controls.
If the boiler is being connected to an E10 tariff the 3 core flex if already fitted, must be removed
and a link fitted between terminal 1 & 2 as shown in diagram 2.6.2b on page 18.
It is also advisable to fit the off-peak control when using a wet electric tariff other than Domestic
& Economy 2000 to enable a reduction in running costs.
IMPORTANT
If the boiler is connected to Scottish Power Domestic & Economy 2000 tariff it requires a
permanent mains supply through an external isolator (rated to 3amp) which must isolate any
heating system controls see diagram 2.6.2b
Any heating system controls must not interrupt the mains supply to the boiler.
Standard colours are Brown- Live, Blue- Neutral and Green and yellow- Earth. Make the earth cable
of a greater length so that if the cable becomes strained the earth would be the last to become
disconnected.
CAUTION: IT IS ESSENTIAL TO MAKE SURE THAT THE POLARITY IS CORRECT.
2.6.5 Heating system controls
All external controls and wiring are required to provide a minimum of reinforced insulation at 250 vrms
between the parts of those devices operating at mains hazardous voltage and the user accessible parts
of those devices.
Note: for further information, see the building regulations 1991- conservation of fuel and power, 1995
edition- appendix G, table 4B.
When any kind of external heating system controls are being used to regulate the heating system
connect a single pole type, to the appropriate terminals of the connector shown in diagram 2.6.2b, or (to
the 2 core cable provided).
If the installation requires protection by a “Frost Thermostat” connect a single pole type, between
terminals 6 and 9 shown in diagram 2.6.2b.