Ariston microGENUS 23 MI User manual

User’s
Manual

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Dear Customer,
Thank you for choosing an ARISTON
boiler.
We guarantee that your boiler is a reliable
and technically sound product.
This User's Manual provides detailed
instructions and recommendations for
proper installation, use and maintenance.
Remember to keep this manual in a safe
place for future reference i.e. by the gas
meter.
Your local MTS Servicing Centre is at your
complete disposal for all requirements.
The guarantee on this appliance is
valid for 24 months from the first
day of installation.
Repairs to the electric, hydraulic
or gas circuits may be carried out
only by your local authorised MTS
Servicing Centre.
Every attempt has been made to avoid
errors of any kind
in this User's Manual, the Management
invites customers to inform
of any inaccuracies which they may find.
This will help to improve our service
GROUP

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TABLE OF CONTENTS
1. GENERAL INFORMATION page 4
Technical Information page 5
Control Panel page 6
2. OPERATING INSTRUCTIONS page 8
3. USEFUL INFORMATION
AND TROUBLESHOOTING page 14
4. MAINTENANCE page 16
5. CHANGE OF GAS TYPE page 16
6. TIME CLOCK page 17
IMPORTANT!
Please read this manual carefully.
For additional information, please consult the “Installation and Servicing
Instructions.”
Make sure to keep the manuals provided with the appliance so that they
can be used by the end-user, installer or our authorised engineer.

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1.GENERALINFORMATION
MTS (GB) Limited support the
initiative.Your installer will give you, and
show you how to use, a logbook which will
give you important information about your
boiler, and heating system.Please have
this logbook to hand whenever you
contact a service engineer or us.
All CORGI Registered Installers carry a
CORGI ID card,and have a registration
number.Both should be recorded in
your boiler logbook.You can check
your installer is CORGI registered by
calling CORGI direct on :- (01256)
372300.
This is a combined appliance for the
production of central heating (C.H.) and
domestic hot water (D.H.W.).This
appliance must be used onlyfor the
purpose for which it is designed.The
manufacturer declines all liability for
damage caused by improper or negligent
use.
Do not allowchildren or inexperienced
persons to use the appliance without
supervision.
If you smell gas in the room, do not turn
onlight switches, use the telephone or
any other object which might cause
sparks.
Open doors and windows immediately to
ventilate the room.
Shut the gas mains tap (on the gas meter)
or the valve of the gas cylinder and call
your Gas Supplier immediately.
If you are going away for a long period of
time, remember to shut the mains gas tap
or the gas cylinder valve.
Before any intervention within the
boiler it is first necessary to cut off the
electrical power supply by turning the
external switch to “OFF”.
This manual may be kept in the front
panel of the boiler.

TECHNICAL INFORMATION
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GENERAL DATA
Heating input max-min
Heating output max-min
Efficiency at Maximum Thermal Capacity (see
installation instructions)
CENTRAL HEATING
Operating Temperature max-min
Maximum-Minimum Heating Pressure
Built-in expansion vessel - Total capacity
DOMESTIC HOT WATER
Maximum-Minimum Temperature of
Water for Domestic Use
Working pressure max-min
Flow rate ∆T 25°C
Flow rate ∆T 35°C
Minimum flow rate
ELECTRICAL DATA
Electrical Supply/ Frequency
Power Consumption
Protection of Electrical System
CATEGORY
Nominal Pressure/Methane Gas (G20-G25)
Nominal Pressure/Liquid Gas (G30-G31)
kW
kW
%
°C
bar
litres
°C
bar
l/min
l/min
l/min
V/Hz
W
IP
mbar
mbar
25.6-11.0
23.8-9.7
92.9
82-42
3-0.7
6
56-36
8-0.2
13.6
9.7
2.6
230/50
140
X4D
20-25
30-37
23 kW 29.8-12.0
27.8-10.5
93.5
82-42
3-0.7
6
56-36
8-0.2
?
?
2.6
230/50
155
X4D
20-25
30-37
27 kW

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CONTROL PANEL
23 MI
23/27 MFFI

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LEGEND:
A - On/Off knob
B - Domestic hot water temperature
adjustment knob
C - Central heating selection
(winter) and temperature
adjustment knob
D - On/Off L.E.D. (green)
E - Fume sensor L.E.D. (yellow)
F - Ignition failure (lockout)
L.E.D. (red)
G - “Economy/Comfort”mode
selection knob
H - Ignition failure (lockout) and/or
overheat reset button
I - Overheat L.E.D. (red)
J - Low system water level
L.E.D. (red)
K - Central heating temperature
L.E.D (yellow)
L - Time clock
M - Heating system pressure gauge

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2. OPERATING INSTRUCTIONS
CAUTION
Installation, start-up, adjustments
and maintenance must be performed
by a competent person only, in
accordance with the current Gas
Safety (Installation & Use)
Regulations and the instructions
provided. Improper installation may
cause damage or injury to
individuals, animals and personal
property, for which the manufacturer
will not be held liable.
To ensure efficient and safe
operation it is recommended that
the boiler is serviced annually by a
competent person.
If it is known or suspected that a
fault exists on the appliance, it must
not be used until the fault has been
corrected by a competent person.
HELPFUL SUGGESTIONS
To get the most out of your boiler, we
have provided you with some useful
advice on proper use and
maintenance:
- Periodically check the system
pressure using the pressure gauge
“M”, make sure that the pressure is
between 1.0 and 1.5 bar (the blue
part on the gauge) when the system
is off and cool. The warning L.E.D.
“L”will indicate if the pressure is
below the minimum recommended
M

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value. Consult your installer for
checking and refilling the system.
- The outer panels of the unit's case
must only be cleaned with a damp
cloth. Do not use abrasive cleaners.
The control panel can be wiped with
either a damp or dry cloth. Spray
polishes must not be used on the
control panel surface or knobs. Care
must be taken in preventing any
liquid entering the appliance.
PRACTICAL TIPS
- If the water is very hard, it is
recommended that a water softener
be added to the system so as to
reduce the formation of limescale in
the boiler exchangers. This will
ensure that the efficiency of the unit
remains the same over time,
reducing gas consumption and
maintenance costs.
- If the boiler should be out of use for
a prolonged period, it is
recommended that the electrical
power supply be disconnected and
that the external gas cock be closed.
If low temperatures are expected,
the boiler and system pipe work
should be drained in order to prevent
frost damage.
- To improve comfort and take full
advantage of the heat produced by
the boiler, it is recommended that an
external (room) thermostat be
installed.
- It is good practice to clean and
service the appliance and central
heating system every year.
Call an Authorised Service Centre.

IGNITION PROCEDURE
Turn the selector knob “A”to the “J”
position. The green L.E.D. “D”will
illuminate indicating that the boiler is
ready to operate. The centralised
electronic control unit will ignite the
burner, without any manual intervention
but in response to the request for
domestic hot water or heating. If, after
approximately 10 seconds, the burner
has not ignited, the boiler safety
devices will shut off the gas and the red
L.E.D. “F”illuminates. To reset the
ignition system, the reset “H”must be
pressed and released. Should the
boiler fail to ignite a second time, check
that the external gas cock is open.If the
problem persists, contact an
Authorised Service Centre.
WINTER AND SUMMER
OPERATING MODES
In the ‘winter operating mode’, the
boiler will produce both central heating
and domestic hot water. In the ‘summer
operating mode’, the boiler will produce
only domestic hot water.
Using the knobs on the control panel,
10
F
DAH