Trianco CLASSIC 2KW, CLASSIC 6KW, CLASSIC 11KW, CLASSIC 9KW, CLASSIC 12KW Operating And Service Instructions

1

CLASSIC 2, 6, 9, 11 & 12kW BOILER

INSTALLATION, OPERATION AND

SERVICING INSTRUCTIONS

Please read these instructions carefully before installing

and operating this appliance

2

CONTENTS PAGE

HEALTH AND SAFETY 3

PRE INSTALLATION NOTES 4

AFTER SALES INFORMATION 5

INTRODUCTION 6

USERS INSTRUCTIONS 7

SIMPLE FAULT FINDING 8

INSTALLATION INSTRUCTIONS 9

Regulations 9
Health and safety 9
Siting the boiler 9
Fixing to the wall 9
Dimensional details 9
Ventilation 10
Water systems 11 - 12
Multiple boiler installation 12
Wiring instructions 14 - 19

SERVICE INSTRUCTIONS 20

Parts replacement 20 - 21
Fault finding 22 - 26
Spares list 27 - 28

IMPORTANT:
General Information:

To keep your boiler running efficiently DO NOT OBSTRUCT OR COVER any ventilation air inlet on the appliance
or the compartment where it is installed.

To keep the casing clean, switch ‘OFF’ the boiler at the electrical supply, and simply wipe with a damp cloth.

DO NOT use abrasive cleaning fluids as this may damage the stove enamel paintwork.

Important

The electrical supply requirements:­The 2kW boilers and 6kW boilers meet the requirements of EN 61000-3.3.
The 9kW and 11kW boiler must be installed in premises having a service of ≥100A per phase.
The 12kW boiler must be installed in premises having a system impedance of not more than 0.1939 + 0.1939Ω.

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11 - 12
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14 – 19

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20 – 21
22 – 26
27 - 28

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HEALTH AND SAFETY

INFORMATION FOR THE INSTALLER AND SERVICE ENGINEERS

Under the Consumer Protection Act 1987 and the Health and Safety at Work Act 1974, it is a requirement to
provide information on substances hazardous to health (COSHH Regulations 1988).

The Company takes every reasonable care to ensure that these products are designed and constructed to
meet these general safety requirements, when properly used and installed.

To fulfil this requirement products are comprehensively tested and examined before despatch.

This appliance may contain some of the items below:

When working on the appliance it is the Users/Engineers responsibility to ensure that any necessary personal
protective clothing or equipment is worn appropriate to parts that could be considered as being hazardous to
health and safety.

INSULATION AND SEALS

Mineral Fibre, Insulation.

May be harmful if inhaled. May be irritating to the skin, eyes, nose or throat. When handling avoid inhalation
and contact with eyes. Use (disposable) gloves, face masks and eye protection.

After handling wash hands and other exposed parts. When disposing, reduce dust with water spray, ensure
parts are securely wrapped.

GLUES, SEALANTS & PAINT

Glues, Sealants and Paints are used in the product and present no known hazards when used in the manner for
which they are intended.

Notes:

a) Electrical safety checks should be carried out by a competent.

b) It is a requirement of the guarantee and any extended warranty that an annual service is carried out by a

competent person.

Installation Engineers Signature

Company Name (if applicable)

Company Address

Company Tel. No.

4

IMPORTANT PRE-INSTALLATION NOTES

Before installation, it is imperative that the following guidelines are heeded to ensure the trouble-free and
efficient operation of the boiler:

Ventilation and Siting

When siting the boiler in a confined space it is essential that adequate ventilation be provided. This will ensure
that air is allowed to circulate freely around the appliance keeping down the ambient temperatures. Refer to
Ventilation Requirements (page 10) for further details.
Ensure that the area surrounding the boiler is kept free of items which would impede the good ventilation of
the appliance (e.g. Towels, linen, etc).
When siting the boiler, take into account the potential requirement for future servicing. Enough space should
be provided at the front of the boiler to enable an engineer to adequately service and/or replace items such as
the PCB or heat exchanger. Space should also be available for the removal of the front casing panel. Please
refer to siting information (page 9) for clearance dimensions.

Power Supply and Wiring

The power supply to the must meet the minimum requirements of the unit being installed, with special
attention paid to the supply current, cable size, and RCD recommendation. The supply voltage to the appliance
must never drop below 207 volts.
When fitting external controls, such as a room thermostat or programmer, particular consideration should be
given to the wiring of these secondary items into the appliance. Please refer to the wiring instructions (pages
14 to 22) for full details. Any breakdown attended to by T R Engineering Ltd which is found to be caused by an
incorrectly wired appliance will be chargeable.
It is important that the pump is wired back to the boiler as shown in the wiring diagram.

System

Isolation valves must be fitted on both the flow and return pipe work of each boiler to be installed. These are
useful as – as from time to time – the boiler may require draining of water, and the lengthy drawing-off
process can be avoided by the astute placement of these valves. Please refer to page 11 for further details.
Ensure that any isolation valves are open before first use, and that the system is full of water.
The boiler can be fitted only in an upright position, with the flow connection to the top of the boiler.

5

A qualified field service engineer is available to attend a

breakdown occurring during the boiler’s guarantee

period.

The boiler must be made available for attendance during
normal working hours, Monday to Friday.

How to report a fault

Step 1

Contact your installation or service engineer, who
should assess the unit and works carried out on the
appliance prior to requesting the attendance of an
engineer from T R Engineering Ltd.

Step 2

Please note that upon attendance by a T R
Engineering engineer, a charge will be made
where:

-The engineer finds no fault with the boiler.

-The cause of the breakdown is due to parts of the
system not manufactured or supplied by T R
Engineering.

-The cause of the breakdown is due to incorrectly fitted
spare parts, or third-party spares not designed for use
with the boiler.

-The boiler has not been installed in accordance with
these instructions.

-The boiler has not been commissioned by a qualified
engineer.

-The boiler has not been serviced annually since
installation.

-The breakdown occurs outside the guarantee period.

-The appliance has not been maintained correctly.

-The breakdown occurs due to use of the boiler not
sanctioned by these instructions.

-The breakdown occurs as a result of work on the
appliance by an unauthorised third-party.

Important:

Invoices for attendance and repair work by any third
party will not be accepted unless authorised in advance
by T R Engineering Ltd.

Technical Assistance

A team of trained technical advisors are available to
discuss any problem with the appliance. In many cases,
the problem may be solved over the telephone,
eliminating the need for an engineer’s visit.

Before making contact, please have the following
information ready:

-The appliance serial number or your unique customer
identification number (issued upon registration of the
appliance with T R Engineering Ltd).

-A description of the fault and any unusual behaviour by
the boiler before the failure occurred.

-The installation and commissioning dates, and the
details of any annual services.

After Sales Service Information

Appliance Serial No: t

Cust. ID No: t

Installation Date: / / t

Service Centre and Technical Support

Tel: [phone] Fax: [phone]

Hours of Business

Monday – Thursday 8:30am – 17:30pm

Friday: 8:30am – 14:30pm

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1. INTRODUCTION

The Aztec Electric Boiler is a wall mounted electric
central heating boiler designed with smaller properties
in mind. Fitted vertically only and requiring access to the
front and the right hand side of the boiler for servicing.
Once the boiler is switched on it is fully controlled by an
automatic management system which monitors the
safety and running functions of the boiler. Designed to
work on a fully pumped wet system only. The boiler
produces hot water by passing water over electric
heating elements housed in an insulated stainless steel
heat exchanger.

There are five boilers in the range with outputs ranging
from 2kW (6825 Btu/hr) to 12kW (41,000 Btu/hr).

IMPORTANT SAFETY NOTES

Read these instructions before installing your boiler.

The heating system must comply with the latest editions
of British Standards 5449 and The Building Regulations,
and Electrical Wiring Regulations BS 7671.

1. Always switch OFF the electrical supply before

removing the cover.

2. If any part of the boiler is modified, then the

guarantee/warranty will be invalidated.

We recommend that you keep these instructions in a
place near your appliance for easy reference.

The Trianco Aztec Wall Mounted Boiler has been designed to conform to European

Directive/Standards.

EN60335-1:1994/A16:2001, EN60335-2-35:1998/A1:2000, EN55014-1:2000, EN55014-

2:1997, EN61000-3-2:2000 and EN61000-3-3:1995.

THE PERSON(S) WHO INSTALLS THIS APPLIANCE, SERVICES OR CARRIES OUT ANY

REMEDIAL WORK, I.E. ELECTRICAL FAULT FINDING, MUST HAVE SUITABLE ENGINEERING

QUALIFICATIONS.

WARNING: DO NOT SWITCH ON THIS APPLIANCE IF THERE IS ANY POSSIBILTY THAT THE

WATER HEAT EXCHANGER IS FROZEN.

THE INSTALLATION OF THIS APPLIANCE MUST MEET THE REQUIREMENTS OF THE

CURRENT ISSUE FOR ELECTRICAL INSTALLATIONS IEE WIRING

REGULATIONS

7

2. USERS INSTRUCTIONS

The Trianco Aztec boiler has been designed and
constructed to give years of trouble free service and
these instructions are provided to assist you in obtaining
the best performance with the least trouble and cost.

The boiler is fully automatic in operation and requires
little attention other than the setting of the thermostat
and any external system controls such as a room
thermostat and time switch.

IMPORTANT

DO NOT COVER OR BOX IN YOUR BOILER, ALLOW AIR
TO CIRCULATE FREELY AROUND THE APPLIANCE

WARNING: DO NOT ATTEMPT TO SWITCH ON THE
BOILER IF THERE IS ANY POSSIBILTY THAT THE WATER
HEAT EXCHANGER IS FROZEN

Before firing the boiler, ensure the system is full of
water and any valves fitted to system are open.

 Check that the time switch/programmer (if fitted) is

ON and the room thermostat is calling for heat.

 Switch on the electrical supply to the boiler and

after a few seconds the boiler’s green and amber

light should illuminate.

 Set the boiler thermostat to the required

temperature using the control buttons.

 Set the time switch/programmer (if fitted) to the

times and programmers required.

 The boiler will now operate automatically, cutting

in and out according to heat demand.

TO TURN OFF THE BOILER

 Switch off the boiler at the time

switch/programmer (if fitted).

 If the boiler is to be switched off for any length of

time it is recommended that the mains supply to
the boiler is switched OFF.

BOILER CONTROL THERMOSTAT

The boiler control thermostat enables you to select the
temperature of the water leaving the boiler. It is
calibrated between 35°C and 75°C.

Using a small screwdriver set the temperature by
turning the knob to the required setting or when the
case is fitted use the buttons to switch between low and
high (35°C and 75°C in 5 degree increments).

BOILER INDICATOR LIGHT

There are three LED indicator lights on the boiler fascia
panel these are:

LED 1 – GREEN – Power on to the boiler
LED 2 – AMBER – Illuminated- in run mode
Flashing – Temperature satisfied
LED 3 – RED – Boiler fault
LED 4-12 – RED – Temperature lights

If the red LED light flashes, this means a fault has
occurred. This would result in the boiler continuing to
operate at a reduced output.
If the red LED is permanently on, this indicates a fault
has occurred. (See simple fault finding chart on page 8).

ROOM THERMOSTAT

The room thermostat should not be positioned near a
source of heat such as a radiator or exposed to the sun
as this will cause the central heating to switch off before
the room is up to temperature. Follow the
manufacturer’s instructions for best siting position for
the thermostat.

FROST PROTECTION

If the boiler and central heating is shut down for many
hours during very cold weather, the water may be in
danger of freezing. The boiler incorporates a frost
thermostat.
If the system is shut down for a long period during very
cold weather, it is advisable to completely drain the
system. However, frequent draining should be avoided,
especially in hard water areas, as this could lead to
scaling of the boiler waterways.

WARNING: DO NOT SWITCH ON THIS APPLIANCE IF
THERE IS ANY POSSIBILITY THAT THE WATER HEAT
EXCHANGER IS FROZEN.

BOILER PUMP OVERRUN

The pump will overrun for a short period of time after
boiler turns off.

TIME SWITCH/PROGRAMMER

When choosing the operating times for your boiler, it is
useful to remember that central heating usually takes
between half an hour to an hour before it becomes
effective.
It is suggested that the time switch/programmer is set to
bring on the heating about an hour after boiler
shutdown. The timer can therefore be switched off
earlier as an economy measure.

Cleaning Casings

Use hot soapy water applied with a damp dry cloth for
the enamel, then dry with a soft dry cloth.

Simple Maintenance

Ensure that the natural ventilation around the boiler is
not obstructed. If fitted in a compartment ensure all
ventilation grilles are clear.

8

SIMPLE FAULT FINDING

If the boiler fails to start for no apparent reason make
the following checks before calling your service
engineer.

1. Is the green LED light illuminated?

NO

2. If the red LED is permanently illuminated

contact your service engineer.

3. Flashing red LED indicates an open circuit. The

boiler can still be operated. Service engineer
should be contacted.

3. TECHNICAL SPECIFICATION

MODEL

AZTEC

2KW

AZTEC

6KW

AZTEC

9KW

AZTEC

11KW

AZTEC

12KW

ELECTRICAL INPUT

2kW

6kW

9.15kW

11kW

12kW

SUPPLY CURRENT (amp)

8.5A

25A

39A

45A

51A

RCD RATING (amp)

13A

32A

40A

50A

63A

MINIMUM CABLE SIZE (mm)

1 4 6

10

16

WEIGHT (kg)

7.0

8.1

10.6

10.8

10.8

WATER CONTENT (litres

1.0

2.1

3.2

3.2

3.2

WIDTH (mm)

164

164

164

164

164

DEPTH

130

130

130

130

130

HEIGHT

550

823

1073

1073

1073

MAINS SUPPLY

230v 50Hz

MAX OPERATING PRESSURE

3bar

43.5 psi

TEST PRESSURE

6 bar
87 psi

BOILER FLOW TEMPERATURE – Adjustable between 35°C and 75°C, located on the front casing

LIMIT THERMOSTAT – Factory set at 100°C

CASING FINISH – Stove enamelled white

4. Checks to see if all external controls i.e. programmer

or room thermostat are calling for heat.

Resetting the Boiler

If a fault has occurred and the red LED is illuminated but
the pump continues to run, then switching the power off
for 30 seconds and then on again should reset the light.
This may be caused by the ambient temperature around
the boiler being too high. Check to ensure that any boiler
ventilation is not obstructed. If the fault reoccurs contact
your engineer.

IMPORTANT: Electrical safety checks should be carried
out by a qualified electrical engineer.

9

2kW

6kW

9 – 12kW

A

566

839

1089

B

586

859

1109

C

550

823

1073

D

107

107

107

E

164

164

164

4. Installation

Regulations

Installation of the boiler must comply with the following
British Standards and Regulations:
BS 5449 – Forced Circulation Hot Water Central Heating
Systems.
BS 7074 – Part 1 – Code of Practice for Sealed Water
Systems.
The Building Regulations
Part ‘L’ (Northern Ireland)
Current I.E.E. Regulations
Local water undertaking By-Laws

Health & Safety at Work Act

The installer should be aware of his responsibilities under
the Act and provide where necessary, appropriate
protection for persons carrying out the installation. In the
interests of safety a competent engineer should install the
boiler and all wiring must be carried out in accordance with
current IEE wiring regulations.

ALL ELECTRICAL WORK MUST BE CARRIED OUT BY A
QUALIFIED ELECTRICAL ENGINEER TO CURRENT IEE WIRING
REGULATIONS.

SITING THE BOILER

IMPORTANT: NOT TO BE INSTALLED IN A SHOWER
COMPARTMENT OR BATHROOM

The boiler is designed to be fitted in an upright position
only. Ensure adequate clearance is allowed for making water

connections as the boiler can be fully serviced from the
front. The boiler must also be fitted in a dry well ventilated
position, which is not subject to adverse temperature
conditions. (See Ventilation Requirements)

Care should be taken when siting the appliance to make sure
adequate access is available for future servicing of the
appliance. Please note that the PCB and heat exchanger
assembly may require removal during such times.

When installed in a compartment with a hot water cylinder
(see. Fig. 1), we recommend that the boiler is fitted in
position 1; if fitted in position 2, provision should be made at
the front of the boiler to enable the removal of the front
casing. In both cases, where any additional equipment like a
hot water cylinder or system controls are to be fitted after
the boiler has been installed, attention should be given to
ensure that they do not restrict access to the boiler for
servicing.

IMPORTANT

UNPACKING THE BOILER

Carefully open the boiler carton, remove boiler and place in
a safe place until required.

NOTE – ALWAYS STORE THE BOILER IN A DRY PLACE
PRIOR TO FITTING. DO NOT ALLOW THE BOILER TO BE
STORED WITH THE CASING REMOVED.

FIXING BOILER TO WALL

IMPORTANT:
DO NOT CUT FLOW AND RETURN PIPES

1. The boiler should be fitted to a suitable wall in an

upright position. Flow tapping must be at top of boiler.

2. Using fixing dimensions supplied work out position of

boiler, mark four mounting holes and drill 6mm
diameter to a depth of 38mm.

3. Fit plastic wall plugs into holes and fit bottom two

mounting screws.

4. Hang on bottom two screws and push the boiler back

towards the wall and secure in position with top two
fixing screws. The flow tapping must be at top of the
boiler. (continued, page 10)

FLOW ᴓ 22

A B C D E

RETURN ᴓ 22
Fig. 3

MINIMUM CLEARANCES:
FRONT – 150mm
FROM OTHER FIXED EQUIPMENT
TOP – 100mm
BOTTOM – 100mm
L/H SIDE – 50mm
R/H SIDE – 100mm
NOTE: APPROXIMATELY 750MM WILL BE
REQUIRED AT THE FRONT OF THE APPLIANCE
TO ENSURE ADEQUATE ACCESS BY AN
ENGINEER DURING ROUTINE SERVICING.

10

5. Removing four casing screws and washers will allow

casing to be removed.

6. Slide top casing cap upwards this will allow front casing

to slide forward.

7. With the front casing removed fit three strain relief

bushes into base of back panel.

8. Fit pipe sealing grommet into top casing panel and cut

off end to allow pipe to slide through (see diagram)

IMPORTANT: TOP CASING PANEL WITH GROMMET MUST
BE RE-FITTED BACK IN POSITION BEFORE MAKING TOP
PIPE CONECTION. ALTERATION OR FAILURE TO COMPLY
WILL INVALIDATE THE WARRANTY.

9. When re-fitting casings slide front casing back into

position ensure small temperature adjuster on PCB
passes through the hole on the control panel. Slide the
top-casing panel down into position and secure panels
into position using the four screws.

VENTILATION REQUIREMENTS

If the appliance is to be fitted in a confined space or
compartment with a potential ambient temperature of 60°C
or above, it is strongly recommended that adequate
ventilation is provided to prevent the overheating of the
boiler controls. Aeration of 100cm2 will be required to the
compartment, in both high and low level positions.

100cm

2

100cm

2

AZTEC
ELECTRIC
BOILER

11

MODEL

MIN FLOW RATE / Min

AZTEC 2 kW

4 LTRS

AZTEC 6 kW

8 LTRS

AZTEC 9 kW

10 LTRS

AZTEC 11 kW

11 LTRS

AZTEC 12 kW

12 LTRS

WATER SYSTEM

IMPORTANT: USE ONLY COMPRESSION FITTINGS WHEN
CONNECTING THE BOILER TO THE CENTRAL HEATING
SYSTEM

The installation must comply with the requirements of the
following codes of practice.
BS 5449 Part 1 Forced Circulation Hot Water Systems.
BS 7074 Part 1 Code of Practice for Sealed System Water
Systems.
BS 7593 Treatment of water in domestic hot water central
heating systems.

The water system must be thoroughly flushed out with
cold water without the pump in position. Refit the pump
and fill the system. Vent all air from the system. Clear any
air locks and examine the system for water leaks.

IMPORTANT: ENSURE ALL SERVICE VALVES ARE IN OPEN
POSITION.

Ensure boiler is fitted with flow pipe at top and return
pipe at bottom.
The boiler is supplied with 22mm tail pipes top and
bottom for connection to system.
The boiler must be installed using 22mm compression
fittings both top and bottom.
The AZTEC ranges of boilers are low water content boilers
so require a good flow rate at all times (see chart).

AZTEC boilers are approved for use on fully pumped open
vented systems and sealed systems. When fitting on a
sealed system a 3 bar safety valve must be fitted to
system, where thermostatic radiator valves are fitted it
will be necessary to fit a bypass to obtain min flow rates.

IMPORTANT: IF MIN FLOW RATES ARE NOT OBTAINED
THE BOILER MAY GO TO LOCK OUT ON HIGH LIMIT
THERMOSTAT.

Where more than 1 boiler is fitted refer to multiple boiler
instructions.
System must be flushed out before adding inhibitor to BS
7593: 1992 treatment of water in central heating boiler.

IMPORTANT: THIS BOILER IS TO BE FITTED ON FULLY
PUMPED SYSTEMS ONLY.

SEALED WATER SYSTEM
REQUIREMENTS

The installation must comply with the appropriate
requirements of the current issue of BS 4814, BS 5449, BS
6798 and BS 7074 Part 1 and 2.

THE INSTALLATION ENGINEER MUST BE REGISTERED AS
A COMPETENT UDHWSS INSTALLER.

Safety Valve

A safety valve set at 3 bar must be fitted with the drain routed
to the outside of the building. The drain must not discharge

Expansion Vessel Capacity

A diaphragm type expansion vessel, conforming to the current
issue of BS 4814. The expansion vessel must be connected to
the systems at a point close to the inlet side of the circulating
pump. The expansion vessel volume depends on the total
water system volume and the initial system design pressure.
For any system an accurate calculation of vessel size is given in
the current issue of BS 5449 and BS 7074 Part 1.
The water content of the boiler is given in Technical
Specification. Note a higher initial design pressure requires a
larger volume expansion vessel.

The charge pressure must not be less than the static head of
the system that is the highest point of the system above the
expansion vessel.

Capacity of expansion vessel

Where design information is not complete the following chart
(page 12) can be used for selecting the size of the vessel, it
should be noted that the size given in the table take account of
fault conditions.

System Temperature

The normal running temperature of the system is 75°C, if a
fault was to occur then the safety device would allow the
system temperature to rise to 100°C. It is recommended that
this figure be used in the calculations of vessel size.

Connection of the expansion vessel

The expansion vessel should be connected in the neutral part of
the system this being the return pipe work close to the boiler,
refer to sealed system pipe work layout drawing. (Fig. 12)

Pressure Gauge

A pressure gauge must be permanently fitted in the system
covering a range from 0 to 4 bar. Position where it can be
seen when filling system.

Inhibitor

If using an existing system, take care to drain down the entire
system including the radiators then thoroughly clean out before
fitting the boiler. Attention is drawn to the current issue of BS
5449 and BS 7593 on the use of inhibitors in central heating
systems.

Drain Tapping

A drain tapping must be provided at lowest point of the
system, which will allow the entire system to be drained.

NOTE: Failure to ensure the correct vessel size could result in
premature failure of the expansion vessel which in turn may
adversely affect other components in the system i.e,
circulating pump and diverter valve.

System Makeup

Water loss from the system should be replaced from a
makeup vessel connected to the system. This vessel should be
higher than the top of the system. Alternatively provision can
be made by pre-pressurisation of the system via a temporary
hose connection and through a double check valve (non­return) and stop valve. There must be no permanent
connection to the mains water supply even through a non­return valve.

above an entrance or a window or any public access area, be
clear of any electrical fittings and positioned so that any
discharge can be seen.

12

Safety valve setting (bar gauge)

3 bar

Vessel charge and initial system pressure (bar gauge)

0.5

1.0

1.5

Total water content of system

Vessel Volume

Litre

Litre

Litre

Litre

25

2.3

3.3

5.9

50

4.4

6.7

11.8

75

7.0

10.0

17.7

100

9.4

13.4

23.7

125

11.7

16.7

29.6

150

14.1

20.1

35.5

175

16.4

23.4

41.4

200

18.8

26.8

47.4

MULTIPLE BOILER INSTALLATIONS

Important

Where a greater output is required, more than one
boiler can be used in the same system. However, if
installing a circulating pump with a higher power
demand, the PCB circuit protection fuse may not be
adequate. The pump could be wired using a relay.
See wiring instructions (page 15 Fig. 14) for further
details.

The boilers must be fitted side by side using common
flow returns. For each additional boiler fitted, it is
recommended that the pipe work is increased in size
and the pump set to deliver the combined flow rates.
The circulating pump will be connected to one of the
boilers or via the relay.

We strongly recommend the positioning of
isolation valves on the flow and return pipe work
of each boiler, as there may be a need to isolate
one or more during servicing. (see Fig. 10)

Please contact the Technical Support team for
further information.

13

Auto

Auto

14

WIRING INSTRUCTIONS

ALL ELECTRICAL WORK MUST BE CARRIED OUT IN
ACCORDANCE WITH CURRENT IEE WIRING
REGULATIONS.

BEFORE COMMENCING INSTALLATION CHECK
POWER SUPPLY TO PROPERTY TO ENSURE THAT
THERE IS SUFFICIENT CURRENT AND VOLTAGE
AVAILABLE FOR SIZE OF BOILER BEING FITTED. TAKE
INTO ACCOUNT REQUIREMENTS OF OTHER
ELECTRICAL APPLIANCES. THE BOILER MUST BE
CONNECTED TO THE MAINS SUPPLY BY MEANS OF A
DOUBLE POLE LINKED SWITCH WITH 3MM CONTACT
GAP IN BOTH POLES.

IMPORTANT: After completing electrical installation

work preliminary safety checks should be carried out
as described in BS 7671:2001.

IMPORTANT:

The electrical supply requirements:­The 2 kW boilers and 6 kW boiler supplies should
meet the requirements of EN 61000-3.3.
The 9kW and 11kW boiler must be installed in
premises having a service supply of ≥ 100A per phase
and meet the requirements of IEC 60417-5855.
The 12kW boiler must be installed in premises having
a system impedance of not more than 0.1939 +

0.1939Ω.

A double pole RCD with trip level sensitivity of 30ma
Can be used capable of breaking full load current to
BS EN61008: 1994.

NOTE RCD UNIT can be used as the isolating switch if
mounted close enough to the boiler.
Miniature circuit breakers MCB MUST be fitted
between RCD unit and boiler and RCD and any
external controls. Refer to technical specification. For
MCB ratings refer to wiring diagram.

It is important the correct size MCB is used in the
supply from the RCD to the boiler. An additional MCB
rated 6 A will be required to supply the external
controls.

ELECTRICAL CONNECTIONS

WARNING: THIS APPLIANCE MUST BE EARTHED.

The mains connection block is located inside the
boiler on a bracket at top left hand side of the boiler
which can be directly wired to the boiler MCB. Use
the correctly rated cable.

Where the pump is wired directly back to the boiler
both live and neutral connection must be used with
the earth being wired back to the earth post. This is
important as the pump is controlled by a switched
neutral. This also applies to pumps being controlled
by a relay.

IMPORTANT: CORRECT POLARITY MUST BE
OBSERVED WHEN BRINGING THE MAINS SUPPLY
INTO THE BOILER.

15

WIRING INSTRUCTIONS
(CONTINUED)

3 PHASE SUPPLY CONNECTIONS FOR 2 OR
MORE BOILERS

MAINS SUPPLY CABLES
Connect each boiler to each phase.

CONTROLS SIGNAL
Wire as shown in wiring diagram.

PUMP CONNECTIONS
The pump to be connected to one boiler only.

See wiring diagram.

IMPORTANT: ALL ELECTRICAL CONNECTIONS
SHOULD BE CHECKED, LOOSE CONNECTIONS CAN
CAUSE PROBLEMS.

WARNING: THIS APPLIANCE MUST BE EARTHED

1. Any exposed pipe work must be earthed in

accordance with IEE regulations.

2. On completion of installation all electrical; work

must be tested to IEE regulations and NICEIC
inspection and completion certificate must be
issued.

IMPORTANT: When a 3-phase supply, a warning
notice MUST be placed by the boiler to indicate a
voltage in excess of 250V.

16

WIRING DIAGRAM FOR HEATING ONLY

17

WIRING DIAGRAM FOR S PLAN CONTROL SYSTEM

18

WIRING DIAGRAM FOR Y PLAN CONTROL

SYSTEM

19

ELEMENT 1

ELEMENT 3

ELEMENT 4

This link needs to be left connected on

installation.

20

5. SERVICING

To ensure reliable operation of your Aztec electric boiler,
it is recommended that you have your boiler serviced
once a year.

The person(s) who services or carries out any remedial
work, i.e. electrical fault finding, must have suitable
engineering qualifications.
Isolate mains supply before carrying out any service
work.

1. Check all electrical connections on PCB and electric

elements to ensure they are secure and clean.

2. Check electrical insulation on wiring.

3. Ensure all air grilles are clean and free from

obstructions.

4. Inspect seals around elements and also the heat

exchanger top and bottom flanges.

PARTS REPLACEMENT

Casing removal

IMPORTANT

Isolate mains electrical supply to the boiler before
carrying out any maintenance work.

1. Isolate electrical supply to boiler.

2. Remove 4 fixing screws securing front casing in

position.

3. Slide top casing upwards this will allow front casing

to slide forward.

FIXING SCREWS
TOP AND BOTTOM

4 FIXING
SCREWS

PCB
CONTROL
UNIT

IMPORTANT: All electrical connections should be
checked. Loose connections can cause problems.

This boiler is fitted with a manual reset high limit
thermostat. Before replacing any part, ensure that the
thermostat does not require re-setting.

PCB Assembly Replacement

1. Ensure electrical supply is isolated to boiler.

2. Remove the 4 fixing screws and washers (2 at top/2

at bottom), lift up the top-plate and carefully slide
off the front casing panel.

3. Disconnect the pump + Call plug, the thermistor

plug and the high limit stat plug.

4. Disconnect all element cables apart from the rear

element. N.B. Take note of wiring arrangement
before disconnecting.

5. Now remove the grey pipe insulation, it is now

possible to disconnect the remaining element.

6. With all elements disconnected, again taking note

of wiring arrangement, carefully disconnect and
remove the element cables from the PCB.

7. Important: Care MUST be taken when handling the

PCB.

8. For ease of access disconnect from the main

terminal block both the red + black cables and also
the power input cables, leaving the earth cable
connected.

9. Free both the pump and call terminal blocks by

removing the terminal block fixing screws.

10. Finally remove the 4 fixing screws holding the PCB

to the bracket.

21

HIGH LIMIT THERMOSTAT REPLACEMENT

1. Ensure electrical supply is isolated to boiler.

2. The high limit thermostat can be found fixed to

top front face of boiler.

3. Remove 2 terminal connectors from high limit

thermostat loosen retaining straps and slide
thermostat out from behind.

4. Important when replacing the thermostat ensure

a heat sink compound is used between back of
thermostat and face of boiler. (see diagram for
positioning)

5. Inspect retaining straps and replace where

necessary.

THERMISTOR REPLACEMENT

1. Isolate electrical supply to boiler.

2. Thermistor is located fixed to top front of

boiler above high limit thermostat.

3. Disconnect from PCB board and slide out from

behind retaining strap.

4. Important when replacing thermistor ensure a

heat sink compound is used between
thermistor and boiler body. (see diagram for
positioning)

5. Inspect retaining strap and replace where

necessary.

6. When replacing front casing, ensure the

thermostat control shaft passes through hole in
front control panel.

FIG. 23

ELEMENT REPLACEMENT

1. Isolate electrical supply to boiler.

2. Drain down system.

3. Disconnect terminal connectors from high

limit thermostat.

4. Remove thermistor from behind retaining

strap.

5. Disconnect electrical elements and earth wire.

6. Disconnect compression fitting top and bottom

of boiler.

7. Remove securing bracket on bottom of boiler

then carefully remove top bracket.

8. Boiler unit can now be carefully removed.

9. Remove eight fixing screws on top flange and

withdraw element assembly.

10. Remove bottom element positioning bracket.

11. Remove damaged element.

12. Refit in reverse order, ensure element seals are

fitted.

13. Check for continuity through two terminals on

each element.

IMPORTANT

Inspect all seals and change where necessary.

22

FAULT FINDING

Red LED permanently illuminated
indicates one of the following faults.

High limit thermostat has operated or faulty
electrical connections

The high limit thermostat is fitted to the front top of the
copper heat exchanger and secured in position with 2
retaining clamps.
Check electrical connections on thermostat and PCB to
check thermostat has not failed using multi meter check
continuity across terminals of thermostat.
To reset press red button in centre of thermostat.
Thermostat may have tripped due to one of the
following:-

1. Faulty circulation pump.

2. Isolation valve on system closed.

3. Air trapped in system.

4. Out of calibration limit thermostat.

5. Temperature settings on PCB incorrect.

6. No water in system.

Thermistor

The thermistor is fitted to the front top of the heat
exchanger and secured in position with a clamp; the
other end terminates with a white connector that plugs
on to the PCB.
Check the connections on the board to make sure it is
correctly fitted; also inspect the thermistor for any
broken wires.

Mains Inlet Wiring

If the mains supply to the boiler is wired incorrectly on
the inlet terminal block. Check polarity.

PCB Board Damage

Inspect the LED lights and the boiler temperature control
adjuster for any damage to connections to PCB
controller.

Voltage Drop

If the voltage drops below 207 volts.

Red LED flashes indicates one of the
following faults.

Poor electrical connection

Check the electrical connections to the elements and the
PCB controller, a poor controller would show up a fault.

Element Failure

To check elements for failure, disconnect each individual
element and check continuity through the element, if
there is continuity between the two terminals the
element is ok. Check each element individually replacing
the electrical connectors after testing.

Element Cables

If there is a break in the element cable, this would show
up as a fault. Check all element cables and connections.

Jumpers

Are the jumpers set correctly.

Green LED

If the green LED is illuminated but the boiler is not
functioning, check that any external controls fitted are
calling for heat.

Blown Fuse on Board

If there is power to the boiler but no LED illuminated
then the fuse on the PCB may have blown. The fuse is
located at the top edge of the PCB. (fuse type 20mm 1A
anti-surge Bessman type S560)
The fuse may have blown due to one of the following:-

1. When multiple boilers are fitted and a larger pump

is used.

2. If the call terminal is used to supply power to

ancillary controls.

RCD UNIT TRIPS

Check that the RCD unit is correctly rated for boiler size.
If under size change.
Inspect mains terminal block wiring for short-circuiting.
Check electrical elements for earth continuity, if element
is found to be faulty fit new element.

Thermistor Values

Temperature

Resistor Value

0

32554

5

25339

10

19872.2

15

15698.5

20

12487.7

25

10000

30

8069.1

35

6534.7

40

5329.9

45

4371.7

50

3605.3

55

2988.7

60

2490

65

2084.4

70

1753

75

1480.9

23

IS THE

PROGRAMMER

TURNED ON I.E.

CALL SIGNAL?

CHECK EXTERNAL

CONTROLS ARE

CALLING FOR

HEAT

IS CALL WIRE LIVE I.E. LINE

VOLTAGE?

CHECK

ELECTRIC

SYSTEM

CICIRCUIT

NO

NO

YES

IS THE HEAT EXCHANGER

GETTING UP TO

TEMPERATURE – AMBER ON

OR FLASHING?

YES

YES

ARE ISOLATING

VALVES OPEN?

NO

OPEN

ISOLATING

VALVES

YES

NO

CHANGE PCB

IS THE PUMP

RUNNING?

YES

CHECK SYSTEM

PRESSURE & PIPE

WORK FOR AIR

LOCKS

NO

CHECK LIVE &

NEUTRAL TO PUMP

LIVE & NEUTRAL

OK?

CHANGE PUMP

NO HEAT – PERMANENT GREEN LIGHT

24

REPLACE

CABLES

ARE CABLES AND

CONNECTIONS

OK

NO

YES

IS THERE POWER

TO ALL

ELEMENTS

NO

ARE JUMPERS

SET CORRECTLY

YES

CHANGE PCB

YES

IS THERE
CONTINUITY
ACROSS THE

ELEMENTS

NO

REPLACE ELEMENT

OR HEAT

EXCHANGER

CHANGE PCB

DOES THE

PUMP GIVE

CORRECT FLOW

YES

YES

FLASHING RED LIGHT

25

IS INCOMING POWER

SUPPLY OK?

PERMANENT RED LIGHT

ARE THE LIMIT

STAT

CONNECTIONS

IS THE SYSTEM

PRESSURE

SUFFICIENTLY

CHARGED?

HAS THE HIGH LIMIT

STAT TRIPPED?

DOES THE BOILER

GO STRAIGHT TO

RED LIGHT?

DOES THE BOILER GO

FROM GREEN TO

AMBER THEN RED?

IS THE THERMISTER

CABLE FAULTY?

YES

CHANGE PCB

REPLACE

THERMISTER

CABLE

REPLACE FAULTY

CABLES OR

CONNECTIONS

CHANGE PCB

REFILL TO 1 BAR

& CHECKS FOR

LEAKS

NO

YES

YES

RE-SET HIGH LIMIT

STAT

YES

NO

NO

YES

NO

NO

26

IS THERE POWER TO THE

BOARD?

RESET RCD

NO GREEN LIGHT

CHANGE PCB

CHANGE FUSE

AND CHECK

PUMP

CHECK SYSTEM

WIRING

HAS THE RCD

TRIPPED?

IS THERE

POWER TO LIVE

AND NEUTRAL?

HAS THE FUSE

BLOWN ON THE

PCB?

YES

YES

NO

NO

NO

NO

27

20

7

19

18

27 2 17

24 25

26

28 4 3

6

16

1

15 8 12

11

10 9 13/14

22/23

28

ITEM

DESCRIPTION

QTY

2kW

6kW

9kW

11kW

12kW 1 Heat Exchanger Assembly

1

221881

221882

221883

221884

221880 2 PCB Assembly

1

211559

211559

211559

211559

211559

3

Element

1

222641 - - - -

3 - 221802 - - - 3 - -

221850 - -

3 - - - 221850

-

1 - - - 221802

-

4 - - - -

221850 4 Thermistor

1

221824

221824

221824

221824

221824 6 Tube Insulation

1

221863

221826

221843

221843

221843

7

Back Casing Assembly

1

221865

221830

221845

221845

221845

8

Front Casing Assembly

1

221867

221821

221847

221847

221847 9 Bottom Pipe Bracket

1

221815

221815

221815

222093

222093

10

Pipe Bracket

1

221814

221814

221814

221814

221814

11

High Limit Thermostat

1

221825

221825

221825

221825

221825

12

Jubilee Clip

2

95256

95256

95256

95256

95256

13

Cable Gland

1

210796

210796

210796

210796

210796

14

Locknut

1

210797

210797

210797

210797

210797

15

Gasket

1

221807

221807

221807

221807

221807

16

22mm Pipe Insulation

1

99285

99285

99285

99285

99285

17

Duct Top

1

221793

221793

221793

221793

221793

18

Top Pipe Bracket

1

221796

221796

221796

221796

221796

19

Top Cap

1

221791

221791

221791

221791

221791

20

Snap In Protection Grommet

1

221787

221787

221787

221787

221787

22

Cable Gland

1

210796

221825

221887

221887

221887

23

Locknut

1

210797

221886

221888

221888

221888

24

Label Call

1

221965

221965

221965

221965

221965

25

Label Pump

1

221964

221964

221964

221964

221964

26

Terminal Block

1

96278

96278

96278

96278

96278

27

Fuse 1A

1

211563

211563

211563

211563

211563

28

Switch Assembly

1

211562

211562

211562

211562

211562

29

30

T R Engineering Ltd

Unit 7 Newton Chambers Way

Thorncliffe Industrial Estate

Chapeltown

Sheffield

S35 2PH

United Kingdom

Tel: [phone]

Fax: [phone]

E-mail: [e-mail]

Web: www.trianco.co.uk

© TR Engineering Ltd

Copyright in this brochure and the drawings and illustrations contained in it is vested in TR Engineering Ltd and neither the brochure or

any part thereof may be reproduced without prior written consent.

TR Engineering Limited’s policy is one of continuous research and development. This may necessitate alterations to this specification.

Item No. 221827 December 2013 Revision 16