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Piazzetta MT 361 Installation, Use And Maintenance Instructions

  • Hello, I am your chat assistant. I have analyzed the provided 'Installation, use and maintenance instructions' for the Piazzetta Thermo boiler stove MT 361. This manual contains essential information on the safe and efficient use of the stove. I am familiar with its construction, heating features, safety devices and installation procedures. I can answer any questions you might have about the installation, operation, or maintenance of your device.
  • Can this appliance be used for cooking?
    What material should be used to create a lining wall around the appliance?
    What is the recommended minimum section for the fresh air intake?
    What is the minimum distance from the appliance front to flammable materials?
Dear Customer,
Thank you for having chosen one of our products, which is the result of years of experience and continuous research aimed at making a
superior product in terms of safety, reliability and performance.
This booklet contains information and advice for safe and efficient use of your product.
DT2010001-01
See the guarantee certificate enclosed with the product for the terms, limitations and exclusions.
In line with its policy of constant product improvement and renewal, the manufacturer may make changes without notice.
This document is the property of Gruppo Piazzetta S.p.A.; no part of it may be disclosed to third parties without the written permission
of Gruppo Piazzetta S.p.A.
All rights reserved by Gruppo Piazzetta S.p.A..
• This instruction booklet has been prepared by the manufacturer
and is an integral part of the product. In the event of sale or
relocation of the product make sure this booklet accompanies it,
since the information contained in it is addressed to the purchaser
and to anyone involved in the installation, use and maintenance
of the product.
• Read the instructions and the technical information contained in
this booklet carefully before proceeding with installation, use or
any repairs.
• The observance of the instructions and technical information in
this instruction booklet guarantees the safety of persons and
property; it also ensures more efficient operation and an increased
lifespan.
• Gruppo Piazzetta S.p.A. cannot be held responsible for damage or
injury due to failure to comply with the instructions for
installation, use and maintenance given in this booklet, or due to
unauthorised alterations or to the use of other than original spare
parts.
• Appliance installation and use must conform with the
manufacturer’s instructions as well as with European and national
legislation and local regulations.
• The wall against which the product is to be placed must not be of
wood or any other flammable material. For correct installation it
is also important to maintain safety distances (refer to the section
entitled “MINIMUM SAFETY DISTANCES”).
• Prior to completing installation of the surround, light the heating
appliance and when it has heated up check that the grate and that
the flue connection is correct.
• Check that the floor where the product is to be installed is
perfectly level.
• Do not fix the heating appliance in any way whatsoever, but simply
place it next to the surround.
• When handling the steel parts of the surround or the ceramic
parts it is advisable to use clean cotton gloves to avoid leaving
fingerprints that are difficult to remove at first time of cleaning.
• The fireplace/stove must be assembled by two persons.
• This appliance has been designed solely for heating. It is not
recommended for cooking foods.
• Stop using the appliance in the event of fault or malfunctioning.
• The product you have purchased may differ slightly from the one
illustrated in this booklet since the pictures are only given as an
indication and not an exact portrayal.
UNI EN 832 . . . . . . . . . . . . . . . . . . . . . . . .Thermal performance of buildings - Calculation of energy use for heating
UNI EN 13229 . . . . . . . . . . . . . . . . . . . . . .Inset appliances including open fires fired by solid fuels - Requirements and test methods
UNI 10683:2005 . . . . . . . . . . . . . . . . . . . . .Heating appliances fired by wood or other solid biofuels - Installation requirements
UNI EN 13384 . . . . . . . . . . . . . . . . . . . . . .Chimneys - Thermal and fluid dynamic calculation methods
UNI 7129 . . . . . . . . . . . . . . . . . . . . . . . . . .Gas plants for domestic use fed by network distribution
UNI 10847 . . . . . . . . . . . . . . . . . . . . . . . . .Chimneys for generators feeded with liquid and solid flues - Maintenance and inspection
EN 1856-1 . . . . . . . . . . . . . . . . . . . . . . . . .Chimneys - Requirements for metal chimneys - Part 1: System chimney products
EN 1856-2 . . . . . . . . . . . . . . . . . . . . . . . . .Chimneys - Requirements for metal chimneys - Part 2: Metal liners and connecting flue pipes
UNI EN 1443 . . . . . . . . . . . . . . . . . . . . . . .Chimneys – General requirements
DIN 18 895 . . . . . . . . . . . . . . . . . . . . . . . . .Fireplaces
DIN 51731 class of measurement HP2 . .Fuels
IMPORTANT INFORMATION DT2010139-00
REFERENCE STANDARDS DT2010140-02
H07025140 / DT2000666 - Rev. 02
40
English
CONTENTS DT2010187-01
SECTION TITLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .PAGE
1.0 GENERAL RULES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
1.1 SINGLE FLUEWAY OR CHIMNEY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
1.2 SOOT INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
1.3 CHIMNEY STACK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
1.4 FRESH AIR INTAKE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
1.5 INSTALLATION ENVIRONMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
1.6 CAPACITY LOAD OF THE FLOOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
1.7 HEATING CAPACITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
1.8 SUITABLE HEAT INSULATING MATERIALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
1.9 MINIMUM SAFETY DISTANCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
1.10 CONNECTION TO THE FLUEWAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
1.11 LINING WALL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
1.12 HOOD GRILLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
1.13 WOOD MANTEL PROTECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
1.14 PREVENTION OF DOMESTIC FIRES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
2.0 TECHNICAL DATA AND SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
2.1 DESCRIPTION OF THE APPLIANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
2.2 FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
2.3 TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
2.4 PRODUCT IDENTIFICATION DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
2.5 ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
2.6 DIMENSION MT 361 OPEN TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
2.7 DIMENSION MT 361 CLOSED TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
3.0 SAFETY DEVICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
3.1 TEMPERATURE/PRESSURE RELIEF VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
3.2 EXPANSION TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
3.3 VENT AND EXPANSION PIPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
3.4 SELF-OPERATED SAFETY VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
4.0 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.1 HANDLING - UNPACKING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.2 PREPARATIONS FOR INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
4.3 INSTALLATION OF THE SMOKE DAMPER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
4.4 PLUMBING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
4.5 FILLING THE SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
5.0 USE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
5.1 FUEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
5.2 SMOKE DAMPER REGULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
5.3 COMBUSTION AIR REGULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
5.4 LIGHTING FOR THE FIRST TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
5.5 LIGHTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.6 OPENING THE DOOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.7 OPERATION UNDER ADVERSE WEATHER CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . 71
5.8 OVERHEATING AND EXTINGUISHING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
6.0 MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6.1 PERIODIC CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6.2 CLEANING THE CERAMIC CLADDING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6.3 CLEANING THE STEEL PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6.4 CLEANING THE PAINTED METAL PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6.5 CLEANING THE GLASS (DAILY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
6.6 CLEANING THE GRATE AND THE ASH DRAWER (EVERY DAY) . . . . . . . . . . . . . . . . . . . 73
6.7 DISPOSAL OF ASHES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
6.8 CLEANING ALUKER® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
6.9 CLEANING THE SMOKE BAFFLE PLATE AND BOILER . . . . . . . . . . . . . . . . . . . . . . . . . . 74
6.10 MAINTENANCE OF THE WATER SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
6.11 WHEN THE BOILER STOVE HAS NOT BEEN USED FOR SOME TIME . . . . . . . . . . . . . . . 75
6.12 DOOR CLOSING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
7.0 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
H07025140 / DT2000666 - Rev. 02 41
English
This booklet code H07025140 / DT2000666 - Rev. 02 - (12/2010) comprises 80 pages.
1.0 GENERAL RULES DT2011911-00
Before proceeding with installation, choose the most suitable position for your fireplace according to the indications given in the section
“MINIMUM SAFETY DISTANCES” and to all the indications below.
DT2033152-00
FLOOR
PROTECTION
CHIMNEY STACK
FLUE
CONNECTION TO FLUE
SAFETY DISTANCES
SOOT REMOVAL
INSPECTION HOLE
FRESH AIR INTAKE
CHECK FLOOR
LOAD-BEARING CAPACITY
FIXED OPENING
SMOKE DAMPER
ADJUSTMENT
LINING WALL
HOOD GRILLE
PROTECTION FOR
ORNAMENTAL LEDGE
Fig. 1
H07025140 / DT2000666 - Rev. 02
42
English
DT2010169-00
1.1 SINGLE FLUEWAY OR CHIMNEY
Every appliance must have a vertical flue pipe operating by natural
draught to discharge the combustion gases outdoors.
The flue must:
- comply with regulations in force in the place of installation of the
appliance;
- be tight to the products of combustion, waterproof, suitably
insulated and made with materials resistant to corrosion by the
gases and to stress;
- be connected to just one stove, fireplace or extraction hood;
- be properly sized, with constant free internal section, equal to or
greater than the diameter of the flue pipe of the stove and at least
3.5 m in length;
- be mainly in a vertical position with a deflection from the axis of no
more than 45° (Fig. 2);
- be at a suitable distance from combustible or flammable materials,
ensured by an air gap or suitable insulating material;
- be of uniform internal section, preferably round. Square or
rectangular sections must have rounded corners with a radius of at
least 20mm and a maximum ratio between the sides of 1.5
(Fig. 3-4-5);
- have smooth walls if possible and without narrowing. Bends must
be regular and without discontinuity (Fig. 6).
It is forbidden to make fixed or mobile apertures on the flue
to connect appliances other than the one to which it is already
connected.
It is forbidden to pass other air ducts or service pipes inside
the flue, however large it is.
If the flue is an incorrect size or installed other than in
compliance with the above instructions, Gruppo Piazzetta
S.p.A. cannot be held liable for malfunctioning of the
appliance, damage to property or injury to persons or
animals.
DT2010031-01
1.2 SOOT INSPECTION
We recommend that the flue have a chamber for collecting solid matter and any condensate located below the connection and which may
be easily inspected by means of an airtight door. (Fig.1)
DT2030258-00
DT2030050-00
Fig. 2
Fig. 3
MAX 45° NO
X
MINIMUM 3.5 M
Ø
DT2030188-00
Fig. 4
R (min. 20)
Deposit of creosote
DT2030189-00
Fig. 5
P
R (min. 20)
L (<_ 1.5 x P)
Deposit of creosote
DT2030190-00
Fig. 6
NO
NO
X
Minimo 3,5 m
MAX 45°
H07025140 / DT2000666 - Rev. 02 43
English
The chimney stack is a device fitted on the top of the chimney that is
designed to aid dispersion of the flue gas into the atmosphere.
The chimney stack must comply with the following requirements:
-it must have an internal section and shape the same as the flue (A);
- it must have a useful outlet section (B) of not less than twice that of
the flue (A);
- the part of the chimney that emerges from the roof or remains in
contact with the outside (e.g. in the case of a flat roof), must be
covered with brick or tile elements and in any case be well insulated;
- It must be built in such a way as to prevent the penetration of rain,
snow and foreign matter into the flue and to ensure that in the event
of winds from all directions and angle, discharge of the combustion
products is assured (chimney stack with down-draught cowl).
Recommended distances for correct chimney operation.
To ensure trouble-free operation of the chimney and allow correct
dispersion of the flue gas in the air, the chimney stack must be
installed at the distances given below:
- 6-8 metres from any buildings or other obstacles that are higher
than the chimney stack;
- 50 centimetres higher than any obstacles located at a distance less
than 5 metres away;
- outside the reflux area. The size and shape of this area differ
according to the angle of inclination of the roof and it is therefore
necessary to adopt the minimum heights shown below.
Example: Check the slope of the roof (column
α
), and the
anticipated distance of the chimney stack from the axis of the ridge (column A); if the distance is greater than “A” the height of the chimney
stack may be read in (column H); if the distance is less than “A” the chimney stack must rise above the ridge by 0.5 metres.
6-8 m
A
B*
* B is
double A
FLAT ROOF
SLOPING ROOF
0.50 m
0.50 m
0.50 m above the ridge
height of reflux
area Z
ridge axis
distance more than A
α
H min.
distance
less than A
over 5 m5 m
or less
5 m
or less
FLAT ROOF
SLOPING ROOF
0.50 m
0.50 m
0.50 m above the ridge
height of reflux
area Z
ridge axis
distance more than A
α
H min.
distance
less than A
over 5 m5 m
or less
5 m
or less
Pitch of the roof Horizontal width of reflux
area from ridge axis
Minimum height of
outlet from roof Height of reflux area
ααA Minimum H Z
15° 1.85 m 1.00 m 0.50 m
30° 1.50 m 1.30 m 0.80 m
45° 1,30 m 2.00 m 1.50 m
60° 1.20 m 2.60 m 2.10 m
Fig. 7 Fig. 8
Fig. 9
Fig. 10
Fig. 11
DT2030051-00
DT2030052-00
DT2030053-00
DT2030192-00
DT2030191-00
1.3 CHIMNEY STACK DT2010025-03
H07025140 / DT2000666 - Rev. 02
44
English
To ensure trouble-free operation the stove/fireplace must have the
necessary air available for combustion and this is provided through
the fresh air intake.
The fresh air intake must:
- have a total free cross section at least equal to the size given under
“TECHNICAL DATA”;
- be protected by a grille or suitable guard provided it does not
reduce the minimum recommended section;
- be in a position where it cannot be obstructed.
The airflow necessary for the fire may be obtained in different ways:
- through a fresh air intake direct into the room of installation (it is
advisable to place the air intake behind the appliance so that the air
warms up before flowing into the room through the hood grille);
- with ducting through pipes direct to the room of installation,
increasing the recommended minimum free cross section by at
least 15%;
- from an adjacent room to the place of installation provided this air
flows freely through permanent apertures communicating with the
outside.
The pressure in the adjacent room from which air is taken
must not be lower than the exterior pressure because of a
counter draught caused by the presence in that room of
another appliance in use or of a suction device.
The permanent apertures in the adjacent room must comply
with the requirements given above.
Combustion air must not be taken from adjacent rooms used
as a garage or a combustible materials store or for activities
posing a fire hazard.
1.4 FRESH AIR INTAKE DT2010170-01
H07025140 / DT2000666 - Rev. 02 45
English
Fig. 13
DT2030260-01
Fresh air
intake
Hood
grille
Fig. 12
DT2030259-01
Fig. 14
DT2030261-01
DT2010033-01
1.5 INSTALLATION ENVIRONMENT
The appliance must be installed in a location which allows safe and convenient use as well as easy maintenance. If the appliance being
installed requires an electrical socket, the room must also be provided with an earthed power supply in accordance with current regulations.
The room where the appliance is to be installed must comply with the following requirements:
it must not be used as a garage, store for combustible material or for activities posing a fire hazard;
it must not be in a vacuum in relation to the outside environment due to the effect of contrary draught caused by the presence in
the room where the appliance is installed of another appliance or an extractor device.
Do not use two stoves, a fireplace and a stove, a stove and a wood-fired cooking range, etc. in the same environment, since the
draught of one could affect the draught of the other.
- Devices suitable for cooking food with relative hoods without an extractor fan may only be used in kitchens.
- Gas appliances of type C are allowed (refer to current legislation and regulations in the place of installation)
Gas appliances of type B are not allowed (refer to current legislation and regulations in the place of installation)
The heating appliance must not be used simultaneously with collective type ventilation ducts with or without extractor fan, other
devices or other appliances such as: forced ventilation systems or other heating systems using ventilation to change the air. Such
systems could cause a vacuum in the environment of installation even if installed in adjoining or communicating rooms.
The appliance must not be used: in stairwells except in buildings with no more than two apartments; in corridors for common use;
in bedrooms; in bathrooms or shower-rooms.
DT2010171-00
1.6 CAPACITY LOAD OF THE FLOOR
Check the load-bearing capacity of the floor by adding together: the weight of the protection (lining walls), insulating materials, surround (given
in the surround instruction booklet) and the appliance (given under “TECHNICAL DATA”).
If the floor has an unsuitable load-bearing capacity, take adequate countermeasures.
DT2010130-01
1.7 HEATING CAPACITY
Check the heating capacity of the appliance by comparing the rated power given under
“TECHNICAL DATA”
with the power required by the
environment to be heated.
The energy requirement may be calculated approximately by multiplying the square metres of area by the height of the ceiling; the result is
then multiplied by a coefficient, which depends on the degree of insulation of the building, that is, on internal and external factors of the
dwelling, as described below.
a) Internal factors: type of window and door frames, thickness of the insulation and walls, type of building materials, presence of stairwells,
walls with extensive glazing, high ceilings, position of the rooms to be heated in relation to other adjacent heated or unheated rooms, …
b) External factors: geographical position, average outdoor temperature, exposure, wind speed, latitude, altitude, …
Example of approximate calculation of the energy requirement to heat a fixed volume to 18/20° C
The coefficient that is normally used is determined according to the real conditions as they occur case by case.
- From 0.04 to 0.05 kW per cubic metre in a well insulated environment
- From 0.05 to 0.06 kW per cubic metre in a poorly insulated environment
3 rooms measuring 20m2 X (H ceiling) 2.7m = 162 m3(volume)
In an environment with a good degree of insulation, an average value (coefficient) of 0.045 kW may be taken
162 (volume) X 0.045 (kW) = 7.3 kW necessary (6300 kcal/h)
Conversion 1kW = 860 kcal/h
Consult a heating technician or engineer for a correct check and calculation of the requirement of the environments to be heated
(see “REFERENCE STANDARDS”).
H07025140 / DT2000666 - Rev. 02
46
English
English
DT2010173-01
1.8 SUITABLE HEAT INSULATING MATERIALS
Type of suitable heat insulating materials.
Material: mineral fibre; ceramic fibre; rock wool.
Form: sheets; mat; shells.
Specifications: specific weight of at least 245 kg/m³ with working temperature limit of at least 1000°C.
Thermal conductivity λ(400°C) ≤ 0.1 W/mK
Thickness: as shown in the figures under “MINIMUM SAFETY DISTANCES”.
If the insulating material is not lining the walls, it must be fixed all over the surface of the walls with anchorage points every
30cm.
Material coded “AGI Q132” or “DIN 18895” is allowed for heat insulation.
DT2011906-00
1.9 MINIMUM SAFETY DISTANCES
WALLS
- FLAMMABLE WALLS: the heating appliance may be installed near
flammable walls provided suitable protection consisting of
insulating and non-combustible material is inserted.
To insulate the appliance and to install the surround correctly,
construct a lining wall in non-flammable material (e.g.
plasterboard) and insert a thick layer of insulating material “C”
between the two walls.
Always leave a gap “A” between the appliance and the lining wall.
(Fig. 15 - 16)
- NON-FLAMMABLE WALLS: always leave a gap of 5 cm between
the heating appliance and the lining wall.
CEILING
- FLAMMABLE CEILING: create an 8 cm false ceiling of non-
flammable material.
The minimum distance between the false ceiling and connection to
the flueway must be 20 cm, while the flue connection must be
insulated with at least 3 cm thick non-flammable material that is
resistant to high temperatures. (Fig. 15-16)
If the surround canopy and the flue connection are metal, the
minimum distance from the false ceiling may be reduced to 10 cm,
but the insulation of the connection to the flueway must be at least
6 cm thick.
- NON-FLAMMABLE CEILING: the minimum distance between the
ceiling and connection to the flueway must be 20 cm.
FLOOR
If the floor is made of flammable material, it must be protected with
a layer of insulating material of thickness “E” while an air space “D”
must be left between the heating appliance and the floor. (Fig. 15)
For insulation, use insulating material with the
characteristics given under “SUITABLE HEAT INSULATING
MATERIALS”.
H07025140 / DT2000666 - Rev. 02 47
English
A C
B E D
Flammable
wall
Insulating
material
Flammable
floor
R
8 cm20 cm min.
Fig. 15
DT2032811-00
A
C
R
Flammable
wall
Insulating
material
Fig. 16
DT2032812-00
DANGER AREA FOR RADIATION
There is a radiation area in front of the stove which must be kept free of any flammable element, such as: carpets, curtains, wood furnishings,
ornaments, flammable liquids, fire-lighting products or firewood, etc.
This area is defined by the distance “R”. (Fig. 15 - 16)
Failure to comply with the above could cause a fire!!!
The minimum safety distances to be observed are given in the table below:
H07025140 / DT2000666 - Rev. 02
48
English
MODELS
MT 361
Aclearance from appliance to flammable wall at the side cm 10
Bclearance from appliance to flammable wall at the rear cm 10
Cthickness of insulating material for wall to side/rear cm 12
Dclearance from appliance to flammable floor cm 26 (foot height)
Ethickness of floor insulating material cm 4
Rminimum clearance from appliance front to flammable material cm 150
DT2011907-00
1.10 CONNECTION TO THE FLUEWAY
Connection to the flueway must be done using pipes as short as
possible without narrowing or restrictions and with a maximum slope
of 45°.
Flexible metal or asbestos-cement pipes must not be used
Pipes and bends or elbows must be made in compliance with current
regulations
WARNINGS WITH REGARD TO FLAMMABLE WALLS OR CEILING:
If the connection has to go through elements or walls in heat-
sensitive flammable materials, create a layer of at least 20 cm
insulation around the pipe. (Fig. 17)
After having drilled a hole in the wall to insert the pipe through into
the flueway, the air gaps must be filled with non-flammable, resilient
materials with a reduced capacity of heat transmission (e.g.
lightweight concrete). Fig. 18
Check that the connection to the flueway is gas/smoke-tight, since
the appliance operates in a vacuum.
It is recommended that the connector pipes be insulated with
insulating material having the characteristics given in the
section “SUITABLE HEAT INSULATING MATERIALS”.
Check that the pipe does not penetrate too far into the flueway,
thereby choking the pipe for the passage of smoke and combustion
gases.
45°
FLUE
20
20
Insulation
Wall to be protected
Insulation
Maximum
Fig. 17
DT2030269-01
FLUE
Air gaps
Wall connection
flange
Fig. 18
DT2030270-00
DT2011912-00
English
H07025140 / DT2000666 - Rev. 02 49
English
DT2011913-00
1.11 LINING WALL
The surround or the lining wall of the fireplace must be self-supporting regardless of the materials with which it is made and under no
circumstances must it come into contact with the heating appliance. Furthermore, the surround must be made with non-flammable materials
in compliance with regulations.
For Gruppo Piazzetta S.p.A. surrounds, follow the instructions enclosed with the product.
Testing and lighting for first time
Only a visual inspection can be made in the intermediate stage for heating appliances that must be assembled or clad with brickwork or require
the use of cement binders. In this case operation of the whole installation must be tested after all the building works directly connected with
the “LIGHTING FOR THE FIRST TIME” test have been completed, following the instructions given in the booklet.
DT2010177-00
1.12 HOOD GRILLE
The hood grille has the function of allowing air to pass from inside
the hood to the environment or vice versa if the Multifuoco system
is installed.
Warm air comes out of the hood grille with the natural convection
system and it is therefore necessary to maintain the safety distances
from flammable materials such as: flammable ceilings or walls,
ledges/beams, furniture, curtains, etc.. The hood grille must be
installed at least 50cm from the ceiling and with at least 30cm safety
distance to the sides.
For the hood grille size, see “TECHNICAL DATA”.
A non-closable hood grille must be installed without
connecting it to the stove so that the warm air that has
stratified inside the lining wall can flow out.
With a ceiling over 3 metres high, a NON-CLOSABLE hood
grille must be installed on the hood lining at a height of 30cm
from the ceiling to allow the stratified air to flow out.
MIN. 30 CM MIN. 30 CM
MIN. 30 CM
FLAMMABLE MATERIALS
FLAMMABLE MATERIALS
CEILING IN FLAMMABLE MATERIAL
Fig. 19
DT2030271-00
DT2010178-00
1.13 WOOD MANTEL PROTECTION
Wooden finishes, e.g. wood mantels, may be mounted on the
surround.
Wood mantels must be:
- installed outside the heat radiation area;
- self-supporting;
- installed with 1cm air gap from the surround or from the heating
appliance;
The expansion joint is in ceramic fibre, which has the
function of insulating the surround from the metal structure of
the appliance.
1 cm
Appliance
Hood or surround
1 cm
Surround
Expansion joint
Load-bearing axis
Wood
mantel
Fig. 20
DT2030272-00
English
50 H07025140 / DT2000666 - Rev. 02
DT2010027-02
1.14 PREVENTION OF DOMESTIC FIRES
The appliance must be installed and used in compliance with the manufacturer’s instructions and European and national standards as well
as local regulations.
When a flue pipe passes through a wall or a ceiling, special installation methods must be applied (protection, thermal insulation,
distances from heat-sensitive materials, etc.) See “CONNECTION TO THE FLUEWAY”
- It is also recommended that all elements made of combustible or flammable material, such as beams, wooden furniture, curtaining,
flammable liquids, etc. be kept outside the heat radiation range of the appliance and at a distance of at least 1.5m from the actual firebox.
-For other information, see “MINIMUM SAFETY DISTANCES” and “CONNECTION TO THE FLUEWAY”.
- The flue, chimney stack, chimney and fresh air intake must always be free of obstructions, clean and checked periodically, that is, at least
twice during the seasonal period from the lighting of the stove and during its use. When the stove has not been used for some time it is
advisable to carry out the checks mentioned above. For further information, consult a chimneysweep.
- Only use recommended fuels (See “FUEL”).
English
51
H07025140 / DT2000666 - Rev. 02
2.0 TECHNICAL DATA AND SPECIFICATIONS DT2012202-00
DT2012189-00
2.1 DESCRIPTION OF THE APPLIANCE
The Thermo boiler stove has been specially designed to produce hot water for the central heating system.
The peculiarity of this product lies in the fact that there is a true boiler fitted inside the actual appliance. The boiler is a tank where the
circulating water “receives” heat both directly from the flame and from the smoke.
Efficiency is also optimized by the structure of the grate with perforated grid to ensure even distribution of the primary air, which is heated
before arriving in the firebox.
Once the water has reached the set temperature, it flows into the system and starts to circulate, becoming a source of heat for the heating
system or, through a boiler, for the hot water system.
1
4
5
5
6
7
8
8
9
9
10
11
12
2
3
13
MT 361
DT2033106-00
No Description . . . . . . . . . . . . . . . . . . . . . . . . . .Qty
1) Enamelled stove MT 361 . . . . . . . . . . . . . . . . . . . . . .1
2) Left grate MT 361 . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
3) Right grate MT 361 . . . . . . . . . . . . . . . . . . . . . . . . . .1
4) Aluker rear panel 538x140 MT . . . . . . . . . . . . . . . . . .1
5) Aluker rear side panel 190x140 MT . . . . . . . . . . . . . .2
6) Aluker right side panel 237x140 MT . . . . . . . . . . . . . .1
7) Aluker left side panel 237x140 MT . . . . . . . . . . . . . . .1
8) Aluker front panel 485x170 MT 361 . . . . . . . . . . . . . .2
9) MT grate grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
10) Ash drawer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
11) Fireguard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
12) Smoke baffle plate . . . . . . . . . . . . . . . . . . . . . . . . . . .1
13) Swivelling smoke baffle plate . . . . . . . . . . . . . . . . . .1
DT2012190-00
2.2 FEATURES
The constructional features of the THERMO MT 361 wood-fired boiler stoves/fireplaces with heat-transfer water are:
- stainless steel stove complete with boiler.
- firebox interior in Aluker.
- grate in Aluker.
- rise n’fall door in ceramic glass heat resistant up to 750°C.
- boiler (4 mm steel).
- manually adjustable primary air.
- calibrated secondary air.
- swivelling smoke baffle plate.
Criteria and devices have been used in designing and making the THERMO MT 361 boiler stoves that satisfy the essential safety
requirements laid down by the Directives: CPD 89/106 EEC.
H07025140 / DT2000666 - Rev. 02
52
English
Fig. 21
DT2011543-00
2.4 PRODUCT IDENTIFICATION DATA
DT2030945-00
PRODUCTION
IDENTIFICATION AND
RATING PLATE
Fig. 22
Product name
Serial number DT2030944-00
DT2012191-00
2.3 TECHNICAL DATA
These data are obtained using beech wood with moisture content below 20% and with intervals between stoking-up of approximately one hour.
Appliance for intermittent use.
Technical data for flue calculations.
U.M. MT 361
Rated heat output kW 26.0
Heat output to the water kW 18.0
Heat output to the room kW8.0
Consumption at rated heat output kg/h 8.0
Thermal efficiency % 76
CO content (with 13% O2) % -
Approved in accordance with standard - EN 13229
Test report No. - -
Boiler capacity l 95
Maximum working pressure bar 1.5
Flue diameter cm 25
Firebox opening (WxH) cm 79x55
Firebox surface area cm23024
Weight (dry – without water) kg 315
Size with packaging (WxDxH) cm 97x76x190
Fresh air intake (recommended minimum section) cm2250
Combustion air flow rate with open intake m3/h -
Convective air inlet/outlet (recommended minimum section) cm2350/350
U.M. MT 361
Rated heat output kW 26.0
Flue gas flow rate g/s 25.1
Average flue gas temp. in the flue °C 278.0
Maximum flue gas temperature °C 318.0
Minimum draught Pa 12
The above values correspond approximately to a flue with section: Ø 30 cm up to 4.5 m in length and Ø 25 over 4.5 m.
Every product is identified by a rating plate showing the model and
the performance of the appliance as well as a plate giving the serial
number.
Both plates are located on the bottom shield below the ash drawer.
A label bearing the serial number is also applied on the back cover of
the “Installation, operation and maintenance” booklet.
Always give the information shown on these plates to the dealer or
the Service Centre when requesting service or spare parts.
H07025140 / DT2000666 - Rev. 02 53
English
DT2012194-00
2.5 ACCESSORIES
Standard accessories
- Front fireguard.
-Removable ash drawer.
- Smoke damper with control.
- Hood grille.
- Fresh air intake with manual control.
- Pipe fittings
-Sensor pocket/holder
Optional accessories
- Rapid heat exchanger / circulation pump kit
- Safety unit kit with open tank
- Safety unit kit with closed tank
- Self-operated valve kit for safety relief system with closed tank
- Heat control kit
1) RAPID HEAT EXCHANGER / CIRCULATION PUMP KIT (optional) consisting of:
- Circulation pump
- Rapid heat exchanger
- Diverter valve
- Ball valves
- Ball check valve
- Water flow switch
- Heat regulator
N.B. Consult a plumbing and heating technician to assess your hot water requirement.
Circulation pump characteristic curves provided with the kit.
Quantity of hot water ΔT 30°C with boiler water at an average temperature of 65°C Litres/min 9.7
Connection Ø “ ¾
Hot water connections Ø “ ½
DT2033005-00
H07025140 / DT2000666 - Rev. 02
54
English
Water flow switch Diverter valve
Heat regulator
Heat exchanger
Circulation pump
Cold domestic
water inlet Ø 1/2 ”
Boiler return
pipe Ø 3/4"
Hot domestic
water outlet Ø 1/2 ”
Delivery to heating
system Ø 3/4"
Inlet for hot water
from fireplace
boiler Ø 3/4"
49
4 8,5 8 156,5 7
49
7,5
12
19,5
53
54
Alimentation
DT2033120-00
DT2033122-00
DT2033121-00
Fig. 24
Fig. 25
2) SAFETY UNIT KIT WITH OPEN TANK (optional) consisting of:
- Temperature/pressure relief valve 90° C / 3 bar
- Safety valve 1.5 bar
- Pressure gauge
- Automatic air valve
- Fittings for connection to the Thermo appliance.
Refer to “TEMPERATURE/PRESSURE RELIEF VALVE”.
3) SAFETY UNIT KIT WITH CLOSED TANK (optional) consisting of:
- Safety valve 2.0 bar
- Pressure gauge
- Automatic air valve
- Fittings for connection to the Thermo appliance.
The RAPID HEAT EXCHANGER – CIRCULATION PUMP is enclosed in a box so that it can be positioned according to available space and needs.
Operation
When a tap is opened to draw off hot water the diverter valve automatically ensures that the hot water leaving the boiler passes into the heat
exchanger instead of going to the heating system, thereby allowing faster heating of hot water.
Rapid heat exchanger – circulation pump kit diagram
Fig. 23
English
H07025140 / DT2000666 - Rev. 02 55
English
4) SELF-OPERATED VALVE KIT FOR SAFETY RELIEF SYSTEM WITH CLOSED TANK (optional) consisting of:
- Self-operated relief valve
- Self-operated valve sensor pocket/holder
5) HEAT REGULATOR KIT (optional) consisting of:
- Heat regulator
- 3 sensors
- 3 pockets/holders
Sensor specifications
• Sensor: NTC 10K @25°
• Operating limits: - 50°C / 130°C
• Measurement limits: 0 – 99°C
• Precision: ±1°C
SUBSTITUTE CIRCULATION PUMP
If the optional kit is not used, the minimum requirements for the substitute circulation pump must be:
- Maximum input: 90 W
- Supply voltage: 230 V a.c.
- Frequency: 50 Hz
- Minimum protection rating: IP 44
- Temperature: 110 °C
- Insulation class: F
- Conformity with standard: CEI EN 60335-2-51
It is also important to check that the relative characteristic curve corresponds as closely as possible to the one given in the diagram on
page 53.
English
56 H07025140 / DT2000666 - Rev. 02
DT2033123-00
2.6 DIMENSIONS MT 361 OPEN TANK
79.4
30
54.8
135.5
39.2
26.7
MM
M
R
R
M
4.5
13
55.5
67.5
9.5
5.7 79 5.7
65.5
16
49 .5
3.3 90.4 3.3
RR
26
171.5
M= MANDATA 1"
R= RITORNO 1"
33
32.5
Ø 25
DT2033124-00
2.7 DIMENSIONS MT 361 CLOSED TANK
79.4
30
54.8
135.5
39.2
26.7
MM
M
R
R
M
4.5
13
55.5
67.5
9.5
5.7 79 5.7
65.5
16
49 .5
3.3 90.4 3.3
RR
26
171.5
M= MANDATA 1"
R= RITORNO 1"
CS= CIRCUITO SICUREZZA 3/4"
CS CS
CS CS
50.5
33
32.5
7
Ø 25
58.5
M = DELIVERY Ø 1”
R = RETURN Ø 1”
M = DELIVERY Ø 1”
R = RETURN Ø 1”
CS = SAFETY CIRCUIT Ø ¾”
English
57
H07025140 / DT2000666 - Rev. 02
3.0 SAFETY DEVICES DT2012195-00
It is very easy to use the closed boiler fireplace, but the minimum safety requirements laid down by standard UNI 10412-2:2009 and the laws and
regulations in the country of installation must be observed.
Devices for installation with OPEN TYPE EXPANSION TANK
- Open type expansion tank
- Vent and expansion pipe
-Filler pipe
- Circulation pump control thermostat (except for systems working with natural circulation)
- Circulation system (except for systems working with natural circulation)
- Warning buzzer activation device
- Warning buzzer
- Temperature indicator
- Pressure indicator
- Automatic thermal cutout (shutdown thermostat– for boilers with automatic fill valve only – in our case useless)
It is also advisable to install a temperature/pressure relief valve, which, upon reaching an upper water temperature limit (90°C),
discharges a minimum flow of water (40 l/h for a direct output of 1000 kcal/h).
Devices for installation with CLOSED TYPE EXPANSION TANK
- Safety valve
- Circulation pump control thermostat
- Temperature indicator
- Pressure indicator
- Automatic temperature control device
- Safety heat exchanger with visible open drain (already mounted and tested inside the boiler fireplace)
- Self-operated valve connected to the safety heat exchanger
- Warning buzzer activation device
- Warning buzzer
- Circulating system
- Closed type expansion tank
When designing the closed boiler fireplace, Gruppo Piazzetta has ensured that it complies with current laws and regulations and has fitted
the actual product with some important safety systems. DT2012196-00
DT2010945-00
3.1 TEMPERATURE/PRESSURE RELIEF VALVE
Supplied with safety unit kit
Device that acts by discharging water from the boiler when the boiler reaches a preset temperature. The supplied temperature/pressure relief
valve activates at 90°C and is coupled to a safety valve that activates at 1.5 bar.
The valves must be connected to a pipe that takes the water to the drains of the dwelling.
H07025140 / DT2000666 - Rev. 02
58
English
DT2012197-00
3.2 EXPANSION TANK
As already indicated, an expansion tank is compulsory when using a closed boiler fireplace.
The function of this device and its importance must be emphasised.
The expansion tank has a dual function: for heating and for plumbing purposes.
From a heating point of view its function is to allow the water, which is an incompressible fluid, to expand or contract. For this to happen the
fluid must be in contact with a gas that can compensate the dilations and contractions of the actual fluid.
Three arrangements are possible:
tank open to the air;
closed tank, containing water and air (or another inert gas) without any separation (self pressurised or pressurised with air or gas under
pressure put in from the exterior);
closed tank, diaphragm type tank with membrane that separates the water from an inert gas (e.g. nitrogen).
The tank open to the air is generally installed at the highest point of the system, since it also has the job of keeping the actual system at a
certain pressure, while the other 2 types can be installed anywhere in the system.
For this reason the ideal location for an open tank is in the loft of a dwelling and therefore requires meticulous protection against freezing:
if the water inside the tank freezes, the tank would no longer be able to cope with the expansion of the water.
The open expansion tank must have a breather pipe 1” minimum dia. which should be positioned at a minimum height of 3 metres
above the highest point of the radiators.
Example of OPEN TYPE EXPANSION TANK sizing
a) Water content in the system: 140 l
b) Water coefficient of expansion: 0.035
Expansion volume: 140 x 0.035 = 4.9 l
Tank geometric volume: 4.9 x 3 = 14.7 => 15 l
Example:
water heated from 10 to 90°C increases in volume by 3.5%: this
means that in a system containing 140 l water, at 90°C there are
another 4.91 litres.
The tank volume must be approx. 3 times the expansion volume.
The volume of the expansion tank for a system containing 140 l must
therefore be at least 15 l.
Example of CLOSED TYPE EXPANSION TANK sizing
a) Water content in the system: 140 l
b) Water coefficient of expansion: 0.035
Expansion volume: 140 x 0.035 = 4.9 l
Tank geometric volume: (Ve ) / [1-(Pi / Ps)] => (140 x 0.035) / [1-(2 / 2.5)] = 24.5 l
Where:
Ve = Expansion volume
Pi = Lower absolute pressure that can be reached [bar]: this is the pre-load pressure of the filling unit or the established minimum limit (e.g.
1 bar) to which the atmospheric pressure must be added (= 1 bar)
Ps = Upper absolute pressure that can be reached [bar]: this is the maximum allowed pressure in the system, guaranteed by the safety
valves (=1.5 bar), to which the atmospheric pressure must be added (=1 bar).
Example:
water heated from 10 to 90°C increases in volume by 3.5%: this means that in a system containing 140 l water, at 90°C there are another
4.91 litres.
The tank volume must be appropriate in relation to the absolute pressure values.
The volume of the expansion tank for a system containing 140 l must therefore be at least 24.5 l.
OPEN TANK
0
10
20
30
40
0 100 200 300
Water content of system (l)
Tank geometric volume (l)
QUICK SELECTION DIAGRAMS FOR EXPANSION TANK
Fig. 26
/