SOLZAIMA SZM W 35 kW User manual

Wood Fired Boiler
Instruction Manual
English
Model
Wood Fired Boiler SZM W 35 kW
Carefully read these instructions before installing, using and servicing the unit.
This instruction manual is provided with the product.
Mod. 515-D

Thank you for purchasing a SOLZAIMA appliance.
Please read this manual carefully and retain it for future reference.
* All products detailed herein meet the requirements of the EU Construction Products
Regulation UE 305/2011), and bear the EC compliance marking;
* This Wood Fired Boiler is designed in compliance with the EN12809:2001 standard;
*SOLZAIMA disclaims any responsibility for damages to the unit if installed by non-
qualified personnel;
* SOLZAIMA is not responsible for any damage to units not installed and used in
compliance to the instructions included in this manual;
* All local regulations, including but not limited to national and European standards,
must be observed when installing, operating and servicing the unit;
* For assistance, please contact your unit's supplier or installer. Please note that you
need to be ready to provide the serial number of your unit, detailed on the
identification plate located on the back panel of the unit and on the sticker attached to
the plastic cover of this manual;
*The technical service must be performed by the unit Installer or Supplier, except on
situations where the assessment performed by the installer or service engineer
determines that SOLZAIMA should be contacted, when required.
Contacts for technical support:
www.solzaima.pt
[email protected]
Tel. [phone]
Address: Rua dos Outarelos; nº 111;
3750-362 Belazaima do Chão
Águeda –Portugal

Table of Contents
1. Package content.................................................................................... 2
1.1 Unpacking the boiler ..................................................................... 2
2. Safety precautions ......................................................................... 2
3. Technical specifications......................................................................... 4
4. Installing the wood fired boiler............................................................... 7
5. Installation requirements........................................................................ 7
6. Installation of ducts and fume extraction systems:................................ 9
7. Hydraulic installation............................................................................ 10
7.1 Calculting the minimum volume for the inertia deposit................11
7.2 Calculation method for the expansion vessel volume................. 12
8. Fuel...................................................................................................... 13
9. First time use....................................................................................... 15
10. Lighting............................................................................................ 15
11. Maintenance and cleaning ........................................................ 16
12. Installation diagrams ....................................................................... 17
13.Life cycle of the wood fired boiler.................................................... 20
14. Sustainability ................................................................................... 20
15. Glossary .......................................................................................... 21
16. Warranty.......................................................................................... 23

1
Solzaima
Solzaima's vision has always been to provide a clean, renewable and most cost-
effective energy. This is why for more than 35 years we've been dedicated to
manufacturing biomass heating units and solutions.
As a result of the persistence and unconditional support from our partner network,
Solzaima is currently the leader manufacturer of biomass heating solutions, in the
back boiler fire for central heating segment, and with its range of free standing fires
and wood fired boilers.
We provide annually approximately 20,000 households with biomass heating
solutions. This effectively demonstrates consumers' interest in more ecological and
economic solutions.
Solzaima has an ISO 9001:2008 quality certification and an ISO 14001:2004
environmental certification.

2
1. Package content
Solzaima ships this unit with the following components:
- Wood Fired Boiler SZM W 35kW;
- Instruction manual;
- Poker.
1.1 Unpacking the boiler
To unpack the boiler, please remove the retractable plastic bag and wrapper that
protect the unit.
2. Safety precautions
Solzaima is not liable for any damages to the unit if the specified precautions,
warnings and operating procedures are not followed.
The units manufactured by Solzaima are easy to operate, and include components
carefully designed to protect both the user and the installer against possible
accidents.
The unit must be installed by authorised personnel only. A declaration of conformity
of the installation must be provided by the installer to the client, stating that the
installer takes full responsibility for the final installation and, consequently, for the
smooth operation of the unit.
This unit is designed for its intended use only. Any contractual and extra-contractual
obligations of the manufacturer are hereby excluded regarding injuries caused to
people or animals or damages to property resulting from faulty installation,
maintenance or misuse of the unit.
After removing the packaging materials, inspect the package contents for integrity
and completion. If the package contents does not match the items listed under 1.
Package contents, please contact your local reseller from whom you purchased the
unit.
All the components that make up the unit and that guarantee its operability and
energy efficiency should only be replaced with original parts, provided by an
authorised technical support centre.

3
The unit must be subjected to maintenance at least once a year, by a qualified
engineer.
This manual is provided with the product. Please make sure you keep it beside the
unit at all times.
For your safety, we provide the following recommendations:
This wood fired boiler is a biomass heating appliance. Please make sure you
read and understand the instructions in this manual before using it.
Before turning on the Wood Fired Boiler, please make sure its hydraulic circuit is
properly connected to the water supply.
The boiler is not intended to be used by children, mentally and physically
challenged people, people with sensory disability or inexperienced users, except
under proper supervision and instructions.
Do not touch the boiler when barefoot, or when any part of your body is wet or
humid;
Do not modify the boiler features without the manufacturer's previous consent.
Do not cover or reduce the size of the vents at the installation area.
The Wood Fired Boiler unit requires an adequate fresh air supply for proper
combustion, so the air tightness of the room or simultaneous operation with other air
extraction devices may prevent the unit to work properly.
A proper combustion requires the availability of ventilation holes. This appliance
must be installed in a well air-ventilated area to guarantee adequate air exchange. Air
vents should be placed at locations where they do not become obstructed, to provide
for an adequate fresh air supply and ensure a proper draught.
Do not leave the packing materials near children.
During normal operation, the unit's door must be kept closed at all times and may
only be opened for supplying wood.
Avoid direct contact with parts of the unit that tend to become hot during
operation.
Check for the existence of any obstructions on the fume duct before turning on
the unit after a long period of inactivity.
This Wood Fired Boiler is designed for residential use in a protected environment.

4
3. Technical specifications
The Wood Fired Boiler SMZ W 35 kW is intended for heating water for domestic use
and to provide central heating. This requires the pre-installation of a central heating
system and a hot water tank equipped with a heat exchanger (if you wish to use the
appliance to supply domestic hot water).
The Wood Fired Boiler W35 is equipped with a large wood capacity combustion
chamber (Fig. 1a and 1b), sturdy and user-friendly. This is an atmospheric (natural
draught) boiler.
The boiler is equipped with three doors:
- Lower door: provides access to the area where the ashes fall through the
grids, for cleaning purposes. It is equipped with a lid for the connection of
the combustion auto-regulator. This regulator controls de water temperature
inside the appliance, preventing it to become too hot when the removed
heating power is lower than the produced heating power.
- Mid door: provides access to the wood supply channel and it is where the
combustion occurs.
- Upper door: provides access to the fume outlet pipe for periodic cleaning.
a) b)
Figure 1 –Section views of the combustion chamber of the wood fired boiler

5
Features
Wood Fired Boiler
W 35 kW
Units
Weight
301
Kg
Height
1280
mm
Width
604
mm
Depth
950
mm
Diameter of the fume discharge pipe
140
mm
Maximum heating capacity
727
m³
Wood log maximum length
700
mm
Maximum thermal power (water)
32
kW
Fuel consumption
10,5
Kg/h
Thermal yield at rated thermal power
77
%
Max. gas temperature
256
ºC
Max operating pressure
3
bar
Draught in the chimney
25
Pa
Water volume
80
W
Table 1 –Technical specifications
Tests were performed using beech wood with a energy density of 4.2 kWh/kg. The
information above are the findings of product certification tests performed by
independent laboratories accredited to perform biomass combustion appliance
testing.

6
Front Back Side Top
Figure 2 –Dimensions of the Wood Fired Boiler
Figure 3 –Hydraulic circuit connections of the wood boiler

7
4. Installing the wood fired boiler
Before installing, please perform the following steps:
Upon reception, check the product for completeness and to determine that it
does not show any sign of damage. Any damages or defects should be checked
and accounted for before the unit is installed.
Remove the instruction manual from the package and hand it over to the client.
Connect the combustion gas outlet and the external fume exhaust system (for
instance, a flue) using a pipe with a diameter of at least 140 mm.
Perform the hydraulic connection (see section 12).
5. Installation requirements
See figure 4 to obtain the minimum separation distance between the wood fires boiler
and any neighbouring flammable surface.
The top of the boiler must be at a distance of at least 100cm from the ceiling,
especially in rooms with ceilings made of flammable materials.
The base supporting the boiler cannot be made of flammable material, and requires
adequate protection at all times.
a) b)
Figure 4 –Minimum separation distance between surfaces: a) top view of the unit
installation; b) side view of the unit installation

8
Figures 5, 6a and 6b illustrate the basic requirements for installing the boiler flue. The
bottom part of the tube installation must include a T fitting to facilitate periodic
inspection and maintenance operations, as shown in the figure below. Double-walled
stainless steel insulated pipes must be used and properly attached to avoid
condensation.
Figure 5 –Side view of the installation, showing the inspection point.
Figure 6 –Example of standard installations.
WARNING!
Keep combustible and flammable materials at a safe distance.

9
6. Installation of ducts and fume extraction systems:
The exhaust pipe must be designed for this specific purpose, in compliance with
local requirements and applicable regulations.
Important notice! The outlet end of the wood fired boiler exhaust pipe must
be attached to a T-pipe with hermetic lid, to allow for the periodic inspection or
discharge of heavy dust and condensates.
The exhaustion path must have inspection points fitted along the duct to facilitate
any required periodic cleaning and maintenance operations.
In normal operating conditions, the combustion gas flow should create a draught
of 25 Pa, at 1,5 m above the chimney neck.
The chimney should be used to exclusively service the boiler, and not shared with
other appliances.
External chimneys must be made of stainless steel double-walled insulated pipes,
with an inner diameter of 140 mm.
The fume exhaust pipe may generate condensation, so we recommend that
the appropriate systems for collecting condensates are installed.
Failure to comply with these requirements may prevent the proper operation of
the unit. Be sure to follow all the instructions presented on the diagrams.
The boilers operate with the combustion chamber in depression, which is why it
is absolutely necessary that they include a fume exhaust pipe to adequately extract
combustion gases.
Fume duct material: The tubing must consist of 0.5 mm thick rigid stainless steel,
with fastening joints attaching the different sections and accessories.
Insulation: The fume ducts must be double-walled and insulated to make sure the
fumes do not cool down going outwards, which could cause an inadequate circulation
and condensation that may damage the unit.
Output “T-tube”: Always attach a regulator "T-tube" to the output of the boiler.

10
Wind shield terminal: A wind shield terminal must be installed to avoid fume back
flow.
Chimney draught: The installation must ensure the generation of a draught of 25 Pa
(0,25 mbar) when the unit is hot and operating at its maximum power.
7. Hydraulic installation
* Chapter 12 (installation diagrams) contains the optional connection diagrams for
central heating installation, with or without hot water system for domestic use;
*The minimum temperature at which the circulator pump is activated should be
60°C. We recommend that an anti-condensation valve is installed to prevent the risk
of condensation build up inside the chamber;
*The pump must be mounted at the recirculation circuit where the temperature is
lower;
*A boiler thermostat, or aquastat, should be used and mounted at the hot water
outlet pipe, as with the combustion regulator;
*Solzaima recommends that the installation uses an open expansion vessel, with a
20-cm diameter pipe as a minimum, to connect the vessel to the boiler's recirculation
circuit. No vents are required;
*If the installer chooses to perform the installation using a closed expansion vessel,
the vessel dimensions must consider the size of the installation, using 3-bar safety
valves (adequate for temperatures up to 90°C). Additionally, we recommend the
additional installation of a pressure and temperature safety valve (3bar / 90°C).
*To drain the boiler, a tap should be attached to one of the outlets provided for this
purpose at the bottom of the unit;
*The heat transfer fluid to be used should be water with an additive corrosion
inhibitor, non-toxic product, in the quantity recommended by the product
manufacturer;
*The combustion auto-regulator prevents the water temperature inside the appliance
to get too hot, when the removed heating power is lower than the produced heating
power. This is achieved by reducing the primary air admission which reduces the
combustion speed. This is an important safety feature that prevents the water to boil
and/or the pressure to get too high, by triggering the emergency safety features. The
regulator must be attached to the screw thread provided for this purpose, as shown

11
in the diagram, and should be set to close the primary air admission door when the
temperature reaches 80°C –for an optimal performance of any of the appliances
mentioned in this manual, the installation of the combustion auto-regulator is
required.
*If the room where the unit is installed or the transfer fluid piping presents the risk of
reaching a freezing temperature, the installer must add anti-freezing fluid in the
proportion recommended by the manufacturer to prevent freezing at the minimum
absolute temperature expected.
*Before turning on the boiler, make sure the hydraulic circuit is filled with fluid and in
full operation.
*It is critical to be able to access the different components of the hydraulic
installation throughout the life span of the unit, to facilitate periodic maintenance,
assistance and replacement operations of the required parts over time.
7.1 Calculting the minimum volume for the inertia deposit
Pursuant to the EN-303-5:2012 standard, the calculation of the minimum volume for
the inertia deposit is based on the following formula:
VSP = 15*TB*QN*(1-0,3*QH/Qmin)
where:
VSP = inertia deposit minimum volume (l)
TB= combustion time (h)
QN= rated power (kW)
QH= installation requirement (kW)
Qmin= minimum power for the boiler (kW)
Inertia deposit example:
Combustion time: 2 h (time required for the combustion of a firewood load)
Boiler's rated power: 32 kW
Boiler's minimum power: 32 kW
Building's heat load: 25 kW
Minimum volume required =15*2*32*(1-0,3*25/32) ≈ 735 l

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7.2 Calculation method for the expansion vessel volume
The volume for a closed diaphragm (membrane) expansion vessel for heating
system installation is calculated as follows:
where:
V = vessel's volume (l);
e = water expansion ratio. Calculated based on the maximum difference between the
water temperature when idle and the maximum working temperature. Typically, for a
heating system, the standard value of 0,035 should be used;
C = the total water contents of the installation (l);
Pi= initial absolute pressure (bar), at the vessel installation height, represented by the
hydrostatic pressure + 0,3 bar + atmospheric pressure (1 bar). Typically, this is the
pre-charge pressure of the vessel plus 1 bar;
Pf= final absolute pressure (bar) represented by the maximum working pressure of
the installation + atmospheric pressure (1 bar). Typically, this is the safety valve
setting plus 1 bar.
Table 2 –Water expansion rates
The expansion vessel should be sized for a heating system installation with the
following characteristics:
C =water content = 600 l
Phid = hydrostatic pressure at the installation location = 1 bar
Pseg= safety valve pressure setting = 3 bar

13
Solution:
The above formula applies, where:
e =0,035 standard value
Pi = Phid + 0,3 + Patm = 1 + 0.3 + 1 = 2.3 bar
Pf = Pseg + Patm = 3 + 1 = 4 bar
therefore: V = (0.035 · 600) ÷ [1 - (2.3 ÷ 4)] ≈ 49.41 l
You need to check the expansion vessel manufacturer's catalogue to chose a vessel
with a volume similar or higher than the calculated volume.
8. Fuel
Notice:The installation of this unit needs to meet the requirements of all applicable
standards and regulations.
* This appliance uses dry firewood ONLY. It may not be used as an incinerator, nor
should use other materials such as coal, painted wood, varnishes, thinners, liquid
fuels, glues or plastics. Also avoid burning common combustible materials such as
cardboard and straw.
* The firewood should have a low water content (less than 20%) to ensure efficient
combustion, avoid creosote build-up in the smoke duct, and reduce oxidation of the
overall equipment;
* See Table 3 (on the next page), to get the list of some of the types of wood that can
be used in these units;

14
Table 3 –List of types of firewood to be used with SOLZAIMA appliances, their geographical location and
calorific value/behaviour.
Common
name
Scientific
name
Distribution
(total: 18
districts)
Notes
Features
Smoke
Heat
Lighting
Combustion
Speed
Hardness
Pine
Pinus
Bragança, Castelo
Branco, Coimbra,
Guarda, Leiria,
Viana do Castelo,
Vila Real and
Viseu
Predominant
species
Little
High
Easy
Fast
Soft
Cork Oak
(+)
Quercus
suber
Évora, Faro,
Portalegre,
Santarém and
Setúbal
Predominant
species
Little
Very
High
Easy
Regular
Hard
Eucalyptus
Eucalyptus
Aveiro, Porto and
Lisbon
Predominant
species
Alot
Regular
Difficult
Slow
Hard
Holm Oak
(+)
Quercus
ilex
Beja and Évora
Predominant
species
Little
Very
High
Difficult
Slow
Hard
Olive tree
Olea
Entire country
except
mountainous
regions
Less predominant
than above
Little
Very
High
Difficult
Slow
Hard
Oak
Quercus
Entire country,
with range of
subspecies
Less predominant
than above
Little
High
Difficult
Slow
Hard
Ash
Fraxinus
Riverbank areas
(Lower Vouga)
Small numbers
distributed around
the country
Regular
High
Difficult
Slow
Hard
Birch
Betula
High ground
(Serra da Estrela)
Smaller numbers
distributed around
the country
Little
Very
High
Easy
Fast
Soft
Beech
Fagus
Cold and very wet
regions (North of
Portugal –Serra
do Gerês)
Smaller numbers
distributed around
the country
Little
High
Difficult
Slow
Hard
Elm
Ulmus
Entire country
except mountain
regions (wet
regions)
Smaller numbers
distributed around
the country
Regular
High
Difficult
Slow
Hard
Maple
/Sycamore
tree -
Plane tree
Acer
Minho, Beira
Litoral and Serra
de Sintra
Smaller numbers
distributed around
the country
Little
Regular
Regular
Slow
Soft
Poplar
Populus
Entire country, but
mainly in the
Centre
Smaller numbers
distributed around
the country
Little
High
Easy
Fast
Soft
Chestnut
Castanea
Northern and
centre part of
Portugal, and
mountain regions
Smaller numbers
distributed around
the country
Regular
High
Difficult
Slow
Hard
(+): mostly available from firewood sellers
WARNING!
This appliance may NOT be used as an incinerator.

15
9. First time use
Before starting up the unit, please check the following:
* Ask the installer to light up the unit to ensure its overall proper operating conditions;
* When the unit is used for the first time, the paint goes through a curing process
which may generate additional fume in the room. If this happens, you should allow for
a fresh air supply by opening external windows and doors.
The boiler's combustion chamber and panel doors are made of iron plate
painted with high temperature resistant paint which releases fume during the initial
burn due to the paint curing process.
Ensure that the hydraulic circuit is correctly assembled and connected to the water
supply;
You must make sure the room where the unit is installed has adequate air circulation;
otherwise, the unit will not work properly. To make sure the unit operates properly,
you should refrain from using any other air-consuming appliances existing in the
same room (e.g. gas appliances. diesel boilers, etc.), simultaneously with this unit.
10. Lighting
* Open the mid door of the unit;
* Lay a few pine cones (preferred) or fire lighters on the ash grate;
* Put kindling on the top of the pile;
* The firing period is completed when the unit chassis reaches a stable temperature -
the air admission setting is automatically controlled by the combustion regulator;
* The combustion air is retrieved from the room where the unit is installed, therefore
consuming oxygen from the room. You should ensure that any ventilation grids or
other fresh air intake mechanisms remain unobstructed at all times.

16
11. Maintenance and cleaning
The main concern with this appliance is to periodically clean the ashes that
accumulate inside the unit and fume duct. To access the interior of the combustion
chamber, you need to open the doors (Fig. 7a and 7b ). For the fume duct, you need
to scrape the chamber´s inside surface using the poker (Fig. 7c). The ashes are
collected at the bottom of the unit (Fig. 7d).
a) b)
c) d)
Figure 7 –Cleaning the combustion chamber.
Note: However, before startint to clean, you must allow the unit to cool down
completely to prevent a burning accident.

17
12. Installation diagrams
Central heating installation diagram
Figure 8 –Central heating installation diagram.
Central heating installation diagram and RHW
Figure 9 –Central heating and RHW installation diagram