Trianco Aztec Mini Guide

Aztec Mini
Combination & System Boiler
INSTALLATION, OPERATION AND
SERVICING INSTRUCTIONS
Please read these instructions carefully before installing
and operating this appliance
TO BE RETAINED BY HOUSEHOLDER

2
CONTENTS PAGE
HEALTH AND SAFETY 3
PRE-INSTALLATION NOTES 4
AFTER SALES SERVICE 5
IMPORTANT SAFETY NOTES 6
USER INSTRUCTIONS 7/8
FAULT FINDING 9
INSTALLATION - REGULATIONS 10
INSTALLATION – CLEARENCES & VENTILATION 11
INSTALLATION – WATER SYSTEM 12
INSTALLATION – EXPANSION VESSEL SIZING 13
INSTALLATION 14
INSTALLATION – PIPEWORK LAYOUT 15
INSTALLATION – WIRING-EXTERNAL CONTROLS 16
INSTALLATION – TECHNICAL DETAILS COMBI 17
INSTALLATION – TECHNICAL DETAILS SYSTEM 18
BOILER SPARES 19/20

3
HEALTH AND SAFETY
INFORMATION FOR THE USER, INSTALLER AND SERVICE ENGINEER
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 1998).
TR Engineering takes every reasonable care to ensure that its products are designed and constructed to meet these safety
requirements when the products are properly installed and used. To fulfil the requirements, products are comprehensively
tested and examined before despatch.
When working on the appliance, it is the responsibility of the user or engineer to ensure that personal protective clothing or
equipment appropriate to parts that could be considered hazardous or harmful is worn.
This appliance may contain some of the items below:
Insulation and Seals
Glass rope, mineral wool, insulation pads, ceramic fibre and glass insulation.
When handling, avoid inhalation and contact with eyes. These may be harmful and cause irritation to the skin, eyes, nose or
throat. Use disposable gloves, facemasks and eye protection.
After handling, wash hands and other exposed areas. When disposing of materials, limit dust and the risk of inhalation by using
water spray. Ensure materials are securely wrapped.
Seek urgent medical attention if inhaled or ingested. Exposure to eyes and skin should be followed by immediate cleansing of
the affected areas and medical attention if necessary.
Glues, Sealants and Paints
The glues, sealants and paints used present no known hazards when the appliance is used in the manner for which it is
intended.
Notes:
a) Electrical safety checks should be carried out by a competent person.
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.
Please read these instructions fully before installing this appliance.
If in doubt seek expert advice
These instructions should be kept in a place close to the appliance for easy reference.

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 can
circulate freely around the appliance keeping down the ambient temperatures. Refer to Ventilation requirements (Page 11)
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, consider 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 11) for clearance
dimensions. The boiler must be sited vertically and away from strong magnetic fields.
Power Supply and Wiring
The power supply to the premises 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.
System
Isolation valves must be fitted on both the flow and return pipe work. These are useful 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.
Ensure that any isolation valves are open before first use, and that the system is full of water.
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.

5
TR ENGINEERING LTD CUSTOMER AFTER SALES SERVICE INFORMATION
A step by step guide to reporting a fault with your appliance
A qualified field SERVICE ENGINEER is available to attend a breakdown or manufacturing fault occurring whilst the appliance
is under warranty.
The appliance must be made available for service during normal working hours, Monday to Friday (no weekend work or bank
holidays accepted).
A charge will be made where:
 Our Field Service Engineer finds no fault with the appliance.
 The cause of a breakdown is due to other parts of the plumbing/heating system or with equipment not supplied by
TR Engineering Ltd.
 Where the appliance falls outside the warranty period (see terms and conditions enclosed).
 The appliance has not been correctly installed, as recommended (see installation, operating and servicing
instructions.)
NOTE: Over 50% of all service calls made are found to have no appliance fault.
What to do in the event of an appliance fault or breakdown:
Step 1: Always contact your installer in the first instance, who must thoroughly check all his work PRIOR to requesting a
service visit from TR Engineering LTD.
Step 2: If your appliance has developed an in-warranty fault your installer should contact TR Engineering LTD for
assistance from site.
What happens if my Installer/engineer is unavailable?
Step 3: Contact TR Engineering LTD. We will provide you with the name and telephone number of our Service Agent.
However, a charge may apply if the fault is not covered by the appliance warranty (payment will be requested on site by our
independent Service Agent).
PLEASE NOTE: UNAUTHORISED INVOICES FOR ATTENDANCE AND REPAIR WORK CARRIED OUT ON THIS APPLIANCE BY ANY
THIRD PARTY WILL NOT BE ACCEPTED BY TR ENGINEERING LTD
SERVICE CENTRE AND TECHNICAL SUPPORT
Tel: [phone] Fax: [phone]
Hours of Business
Monday to Thursday 8.30am - 5pm
Friday 8.30am - 2.30pm

6
IMPORTANT SAFETY NOTES
INTRODUCTION
The Aztec Mini Electric Combination and System Boiler is a wall mounted electric central heating boiler
designed with smaller properties in mind. Access is required to the front 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 heat exchanger.
The boilers incorporate inverter constant temperature technology which automatically adjusts output to
match demand.
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 warranty will be invalidated.
We recommend that you keep these instructions in a place near your appliance for easy reference.
The Trianco Aztec Mini Combination and System Wall Mounted Boiler has been designed
to conform to
European Directive/Standards EN60335-1:2002 +A15:2011, EN60335-2-35:2002 inc Amd 1,
EN55014-1:2006 +A1:2009, EN55014-2:1997 +A2:2008.
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 POSSIBILITY THAT THE
WATER MAY BE FROZEN.
THE INSTALLATION OF THIS APPLIANCE MUST MEET THE REQUIREMENTS OF THE
CURRENT ISSUE FOR ELECTRICAL INSTALLATIONS IEE WIRING.

7
USER INSTRUCTIONS
The Trianco Aztec Combination 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.
IMPORTANT
DO NOT COVER OR BOX IN YOUR BOILER WITHOUT MAKING SUITABLE PROVISION TO ALLOW AIR TO
CIRCULATE FREELY AROUND THE APPLIANCE
WARNING: DO NOT ATTEMPT TO SWITCH ON THE BOILER IF THERE IS ANY POSSIBILITY THAT THE WATER
INSIDE THE HEAT EXCHANGER IS FROZEN
Before turning the boiler on, ensure the system is full of water and all valves fitted to the system are open.
Switch on the power supply, display will illuminate, and one audible tone should be heard. Observe any error
codes – Refer to table on Page 9.
Boiler Multi-Function Display
Press ON/OFF button to turn boiler on – Standby
In Standby Mode
Power and Heating symbol illuminated, no call from WIFI Thermostat.
Setting Boiler Thermostat
Press “UP” Once – Set Temperature Flashes, Use “UP” or “DOWN” to set Temperature between
30°C - 85°C Press “Confirm” to store.
Setting Domestic Hot Water (DHW) Temperature. Combination Boiler Only
Boiler OFF – Power symbol not illuminated
Press “UP” Once – DHW Temperature Flashes, Use “UP” or “DOWN” to set Temperature between
30°C - 55°C Press “Confirm” to store.

8
USER INSTRUCTIONS
In Standby Mode
Setting Day of Week
Press “Mode” Four times – Day of Week Flashes, Use “UP” or “DOWN” to set current Day Number
1 – 7 Press “Confirm” to store.
Setting Time
Press “Mode” Twice – Hours Flashes, Use “UP” or “DOWN” to set current time.
Press “Confirm” to store.
Press “Mode” Three times – Minutes Flashes, Use “UP” or “DOWN” to set current time.
Press “Confirm” to store.
In Run Mode
Pressing “Time” will cycle between Manual ON/OFF and Timed.
Programmed times must be set using the WiFi thermostat, see separate instructions supplied with the
thermostat.
Restore to Factory Settings
Press “MODE” for 5 Seconds, When the buzzer sounds Factory settings have been restored
Child Lock
Press “CONFIRM” for 3 Seconds, all keys are locked until “CONFIRM” is pressed again for 3 seconds
Frost Protection
In Standby the boiler will monitor the real time water temperature.
If the water temperature is < 5°C the boiler will run automatically until the water temperature has reached
15°C. The heating element will turn off, the pump will continue to run for 5 Minutes.
Cleaning Casings
Use hot soapy water applied with a damp 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.

9
FAULT FINDING
Information codes
Code Protection Function Description
E2
Current leakage Moisture on circuit board or the
boiler has condensation internally
Qualified engineer to remove
cover and dry/inspect circuit
board
E3
Water temperature
sensor
Sensor is short circuit or open circuit Check sensor connection. Check
sensor cable and replace if
required
E5
Indoor temperature
sensor
Sensor is short circuit or open circuit Check sensor connection. Check
sensor cable and replace if
required
F4
Low Water Pressure System is low on water Fill to correct pressure using
filling loop
F6
No water Flow Air in the system, no water or water
pump not working, pump is blocked,
water flow switch blocked, water flow
switch is faulty
Vent system. Check system
pressure. Check pump and flow
switch for blockage/operation
F1
Dry Fire Protection No water flow Fill system and vent
Press and hold TIME key for 6
seconds to re-set
The boiler has built in over temperature protection. If the water temperature exceeds 140°C the limit
thermostat will trip and the screen will be blank.
The thermostat will require re-setting by a qualified person.

10
INSTALLATION
INSTALLATION
Regulations
Installation of the boiler must comply with the following British Standards and Regulations:
BS5449 – Forced circulation hot water central heating systems.
BS7074-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 and 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 regulations.
IMPORTANT
ALL ELECTRICAL WORK MUST BE CARRIED OUT BY A QUALIFIED ELECTRICAL ENGINEER TO CURRENT IEE
WIRING REGULATIONS.
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.
SITING THE BOILER
IMPORTANT: NOT TO BE INSTALLED IN A SHOWER
COMPARTMENT OR BATHROOM
Ensure adequate clearance is allowed for making water connections. Access is required to the front of the
boiler for servicing. 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.
The front cover is held in position by four Phillips Head screws, two at the top and two at the bottom.
Clearance at the top and bottom of the boiler should be adequate to allow access with a small Phillips
screwdriver.
When removing the cover please unplug the cable between the display and main circuit board.
The boiler must be mounted on a suitable wall capable of bearing the weight of the boiler.
Utilise all 6 fixing points on top and bottom fixing brackets.

11
INSTALLATION
Clearances
Please allow adequate clearance in front of the boiler for servicing and end user access.
VENTILATION REQUIREMENTS
If the appliance is to be fitted in a confined space or compartment it is a requirement that adequate
ventilation is provided to prevent the overheating of the boiler controls. Aeration of 110 cm² will be required
To the compartment, in both high and low positions.

12
INSTALLATION
WATER 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 Water Systems.
BS 7593 Treatment of water in domestic hot water central heating systems.
Isolation valves must be fitted.
The water system must be thoroughly flushed out before adding inhibitor to BS 7593: 1992 treatment of water
in central heating boiler.
Fill the system. Vent all air from system. Vent Pump. Clear any air locks and examine the system for water
leaks.
IMPORTANT: ENSURE ALL SERVICE VALVES ARE IN AN OPEN POSITION.
IMPORTANT: THIS BOILER IS TO BE FITTED ON FULLY PUMPED SYSTEMS ONLY.
IMPORTANT: COMBINATION BOILER ONLY – ALL DOMESTIC HOT WATER OUTLETS SHOULD BE RESTRICTED TO
5L/M
SEALED WATER SYSTEM REQUIREMENTS
The installation must comply with the appropriate requirements of the current issue of BS4814, BS5449,
BS6798 and BS7074 Part 1 and 2.
Safety Valve
A 3-bar safety valve is fitted within the unit. The drain must be routed to the outside of the building. The drain
must not discharge 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.

13
INSTALLATION
Expansion Vessel Capacity
Note the internal 5 litre expansion vessel might not accommodate the entire system volume.
A second diaphragm type expansion vessel, conforming to the current issue of BS4814 might be required. 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 BS5449 and
BS7074 Part 1.
The water content of the boiler is given in the 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, which is the highest point of the
system above the expansion vessel.
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.
Capacity of Expansion Vessel
Where design information is not complete the following chart 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.
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 (litre) Vessel volume (litre)
25 2.3 3.3 5.9
50 4.7 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
System Temperature
The normal running temperature of the heating 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.
Pressure Gauge
A 0 to 4 bar pressure gauge is fitted within the unit.
Drain Tapping
A drain tapping is provided on the boiler. An additional tapping must be provided at the lowest point of the
system, which will allow the entire system to be drained.

14
INSTALLATION
System Makeup
Provision can be made by pre-pressurisation of the system via a temporary hose connection and through a
double check valve (non-return) and stop valve.
There must be no permanent connection to the mains water valve supply even through a non-return valve.
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 BS5449 and BS7593 on the use of
inhibitors in central heating systems.
Magnetic Boiler Filter
To be fitted in the return pipe work close to the boiler.
Scale Inhibitor
The Aztec Mini Combination boiler MUST be fitted with an inline scale inhibitor (not supplied) on the cold feed
inlet pipe.
Failure to do so will invalidate the warranty.
Water Connections

15
INSTALLATION
Pipe Work Layout
Combi
System – Heat Only – Sealed System

16
INSTALLATION
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 enough current and
voltage available for size of boiler fitted. Consider 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
NOTE: RCD unit can be used as the isolating switch if mounted close enough to the boiler.
Miniature circuit breakers MCB’s 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.
ELECTRICAL CONNECTIONS
WARNING: THIS APPLIANCE MUST BE EARTHED.
The mains connection block is located inside the boiler on a bracket at the top right-hand side of the boiler
which can be directly wired to the boiler supply MCB. Use the correctly rated cable.
IMPORTANT: CORRECT POLARITY MUST BE OBSERVED WHEN BRINGING THE MAINS SUPPLY INTO THE
BOILER.
External Controls
THP1002 Series Wi-Fi Thermostat
The boiler is supplied with a Wi-Fi wall mounted thermostat which allows the end user to control the heating
from a smart phone or tablet.
The thermostat requires a 230V supply and communicates with the boiler via a twin core cable.
Connect between terminals 1 & 2 and the twin core cable inside the boiler using the connections provided.
For further information on installing and using the thermostat please refer to the installation manual supplied.

17
TECHNICAL DETAILS
Combination Boiler
*¹ Electrical input for domestic hot water on all combination boilers equals 12kW.
*² With flow restrictors fitted to all domestic hot water outlets.
TECHNICAL DETAILS UNIT 8kW 10kW 12kW
Electrical Input kW*¹ 12 12 12
Supply Current Amp 51 51 51
RCD Rating Amp 63 63 63
Minimum Cable Size mm 10 10 10
D.H.W @45°C Ltr/min*² 5 5 5
Weight Kg 23
Water Content litres 0.8
Width mm 360
Depth mm 240
Height mm 580
Mains Supply 230V 50Hz
Max Operating Pressure 300 kPa / 3 bar
Test Pressure 600 kPa / 6 bar
Boiler Flow Temperature Adjustable between 30°C and 85°C
Limit Thermostats Factory set at 140°C
CH Flow & Return ¾ BSP Male
DHW Inlet & Flow ½ BSP Male
Maximum Flow Temp CH 85°C
Pressure Gauge 0 – 4 bar
Pressure Relief Valve 3 bar
Pump BGE15-10A
Expansion Vessel 5Ltr charge 1.5 bar
Available System Head 3m
Casing Finish Stove enamelled white

18
TECHNICAL DETAILS
System Boiler
TECHNICAL DETAILS UNIT 8kW 12kW
Electrical Input kW 8 12
Supply Current Amp 35 51
RCD Rating Amp 40 63
Minimum Cable Size mm 6 10
Weight Kg 23
Water Content litres 0.8
Width mm 360
Depth mm 240
Height mm 580
Mains Supply 230V 50Hz
Max Operating Pressure 300 kPa / 3 bar
Test Pressure 600 kPa / 6 bar
Boiler Flow Temperature Adjustable between 30°C and 85°C
Limit Thermostats Factory set at 140°C
CH Flow & Return ¾ BSP Male
Maximum Flow Temp CH 85°C
Pressure Gauge 0 – 4 bar
Pressure Relief Valve 3 bar
Pump 25/60
Expansion Vessel 5Ltr charge 1.5 bar
Available System Head 3m
Casing Finish Stove enamelled white

19
BOILER SPARES
ITEM DESCRIPTION QTY 8Kw
Combi
10Kw
Combi
12Kw
Combi
8Kw
System
12kW
System
1 Outer Cover - 1 1 225001 225001 225001 225001 225001
2 PCB 1 225002 225002 225002 225002 225002
3 Heat Exchanger 1 225003 225003 225003 225003 225003
4 Heating Flow Connection 1 225004 225004 225004 225004 225004
5 DHW Heat Exchanger 1 225005 225005 225005 NA NA
6 DHW Limit Thermostat 1 225006 225006 225006 NA NA
7 Pressure Switch 1 225007 225007 225007 225007 225007
8 Pressure Gauge 1 225008 225008 225008 225008 225008
9 Safety Valve 1 225009 225009 225009 225009 225009
10 Expansion Board 2 225010 225010 225010 NA NA
10 Expansion Board 1 NA NA NA 225011 225011
11 Display 1 225012 225012 225012 225012 225012
12 Display Cover 1 225013 225013 225013 225013 225013
13 Pump 1 225014 225014 225014 225014 225014
14 Heating Flow Sensor 1 225015 225015 225015 225015 225015
15 DHW Flow Sensor 1 225016 225016 225016 NA NA
16 Cable Gland 1 225017 225017 225017 225017 225017
17 Cable Gland 1 225018 225018 225018 225018 225018
18 Boiler Casing 1 225019 225019 225019 225019 225019
19 Cable Clamp 1 225020 225020 225020 225020 225020
20 Heating Limit Thermostat 1 225021 225021 225021 225021 225021
21 5L Expansion Vessel 1 225022 225022 225022 225022 225022
22 Control Box Cover 1 225023 225023 225023 225023 225023
23 DHW Pipe 1 225024 225024 225024 NA NA
24 Cold Water Inlet Pipe 1 225025 225025 225025 NA NA
25 Heating Flow 1 225026 225026 225026 225026 225026
26 Heating Return 1 225027 225027 225027 225027 225027
27 Expansion Vessel Connection 1 225028 225028 225028 225028 225028
28 Pressure Relief Pipe 1 225029 225029 225029 225029 225029
29 Brass valve set 1 225030 225030 225030 225030 225030

20
BOILER SPARES