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Celsius C 25 - 29 boiler system without buffer tank

Celsius C 25 - 29 boiler system without buffer tank
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Celsius C 25 - 29 system package content:

  • Celsius C 25 - 29 solid boiler
  • Celsius boiler anticondensing R-package
  • Celsius safety heat exchanger
  • 3-way motorized zone valve 1"
  • System controller (Euroster 813)
  • *(It need to check the boiler condition annually and every non eletric part annually.)


    Celsius C 25 - 29 solid fuel boiler



    The boilers are suitable for family houses, small apartments, foil and greenhouses, small factory halls and workshops gravity or pump heating.
    These boilers are easy and economical to operate. Their firebox is made of 5 mm thick steel by welding folded edges. These boilers have 3 steel plate doors that serve cleaning, filling, air control.
    Celsius C boilers are easier to clean because of the boiler width- door without sill.



    • Celsius heating system will provide even heat distribution in comparison to an open fire place or stove.
    • Able to produce drinkable hot water,
    • Firebox is 5mm thick resistant steel,
    • Operation is easy and economical,
    • It has big firebox for comfortable loading,
    • Able to connect with other heating sources (maximum 3 bar pressure) in the one heating system.
    • Suitable for radiator, underfloor or combined heating systems.


    Recommended fuels:

    • Firewood and other wooden waste


    • Boiler thermometer
    • Filling/draining trap
    • Fire grates (grills)

    Optional accessories:

    • Heating system controller
    • Celsius anticondensing reycling pump unit to 65 Kw [R]
    • Slag scrapper, ashpan
    • Celsius boiler cleaning package



    Modul C 25 - 29
    Firing door size (mm) 310*330
    Maximum heat output (kW) 29
    Heating-system dependant heatable air-space(m3) 300-500
    Fuel-dependant efficiency (%) 85
    Heating water connection (") 2
    Uptake connection (mm) 150
    Height (mm) 1140
    Width (mm) 555
    Depth (mm) 565
    Weight (kg) 188
    Water volume (l) 73
    Max. operating pressure (bar) 2
    Max. operating temperature (°C) 90
    Test pressure (bar) 4
    Draught demand (g/s) 31,8
    Firebox size (mm) (height*width*depth) 520*330*400





    Height of boiler


    Width of boiler


    Depth of boiler


    Cleaning door


    Firing door


    Secondary draught regulator slot


    Ash removal door (primary draught regulator)


    Forward water connection


    Return water connection


    Uptake connection


    Automatic draught regulator connection


    Manual and automatic draught regulator option


    Filling/draining tap connection


    Boiler thermometer connection






    R-Celsius anticondensing package to 65 kW




    Boiler protection unit to prevent condensation
    Condensation is an often experienced phenomenon during the use of the solid fuel boilers which is always harmful, will cause lifespan shorthening, efficiency drop, and higher heating costs.


    Content of equipment:

    • circulation pump (Grundfos UPM3 25-70 Hybrid)
    • pump hollander (ball tap) 1 piece
    • Celsius boiler protection valve
    • to 65kW KVS 7,2
    • tube thermostat
    • draught regulator


    Principle of operation:



    1. Starting the system (heating the boiler)
    After the launching of the boiler, the thermic valve is fully closed towards the user (gate A) and remains in this condition until the fluid is warmed up by the heating source, gets the opening temperature of the thermic valve (corresponding to the calibration value, f.i. 55°C). During this step the fluid sent by the boiler fully recycles through the by-pass (gate B) so the boiler temperature rises very quickly.



    2. Loading the system (heating the tank)
    Reaching the opening temperature (f.i. 55C), gate A proportionally starts to open while gate B proportionally starts to close. The boiler temperature slowly rises, giving energy to the end user, but the returning temperature will not decrease below the calibrated temperature (f.i. 55°C).



    3. System operation
    Starting from point 2, the flow temperature progressively increases to fully open gate valve A. This will correspondingly close gate valve B. This happens at approximately circa 10k higher than the calibration or opening temperature (therefore in this example at 65c). Now the installation is fully operational the supply fluid temperature can increase to set value.
    For example, if the valve opening temperature is 55°C, then it is totally opened in the direction of A → AB in case of +10°C.








    Celsius safety heat exchanger



    It protects the boiler and environment if the boiler is overloaded and the heating system can not heat distribute (There is not buffer tank and irregular usage).


    Content of equipment:

    • Celsius safety heat exchanger
    • Vent valve
    • Thermostatic security valve (opening temperature 98°C)
    • Pressure security valve (2bar)


    Applicable to the following boiler types:
    Celsius classic, Celsius C and Celsius Combi boiler







    Motorized 3-way zone valve



    Motorized 3-way zone valve with spring return for closed hydraulic systems.


    Technical features:

    • Area of use: heating, conditionning and solar thermal (glycol max. 50%).
    • Power supply 230 VAC, 50Hz, absorbed power: 6W
    • Protection IP22
    • Nominal pressure PN10
    • Room temperature Max. 60°C
    • Fluid temperature: 5÷120°C; short time: 150°C;
    • Nominal opening time: 20 s. Springclosing: 6 s.
    • Kvs value 12,6
    • Without power AB->B
    • Weight 1,3 kg/piece







    Euroster 813 controller



    Operating principle:
    The EUROSTER 813 control unit is a universal microprocessor controller with graphical display. The controller is responsible for the pump to operate on the basis of the difference between the set temperatures. It is possible to set up in the control an automatic disinfection function.


    The control is responsible to turn on the pump on the basis of the difference between the set temperatures to ensure that the container is warmed by only the surplus heat, thus making energy savings.
    The controller has a variety of automatic emergency circuit options.


    You can set the emergency value of solar ebullience. There's an automatic vacation mode available, which takes care of cooling the storage to the set value, overheated by the solar system. This mode is important, if the storage is not used on a daily basis and ebullience of the solar panel will be induced. The keyboard of the control unit is lockable in the purpose of protection of your set parameters, which can cause an error.


    The controller has a security sensor testing, if sensor sings, it will automatically trigger the pumps, preventing the ebullience. The controller has a sensor calibration mode, which allows you to avoid false temperature measurement by the long lines.


    Treatment of controller
    The graphics display of the EUROSTER 813 controller makes it easy to set up the controller. The options of setting the controller:
    - Pressing the +/- buttons at the same time you can reach the menu.
    - Pressing the -/ok buttons at the same time you can lock the keyboard.
    - Pressing the +/ok buttons at the same time you can reach the manual mode, pressing the /+ button you can select the manually accessible devices.


    After entering the menu you can set the following values:

    • time
    • disinfection (on/off)
    • modes
    • maximum emergency starting temperature of collector or boiler
    • minimal starting temperature of pump
    • maximum temperature of storage
    • starting and shutdown temperature of solar delta T
    • temperature of storage/hysteresis
    • calibration of solar sensor
    • calibration of storage sensor


    Controller can be applied to:
    In the case of Vacuum-tube control plane collector, mixed-fired boilers and buffers.
    The pump must not be interrupted by other equipment!






    Operating voltage

    230V, 50Hz

    Rated vattage


    Output load of circuit pump


    Emergency starting temp

    60-190 C

    Min. starting temperature of pump

    15-40 C

    Storage max. temperature

    0-100 C

    Delta T pump starting (on)

    3-20 C

    Delta T pump shutdown

    1-18 C

    Storage temperature

    10-100 C

    Storage hysteresis

    2-20 C






    Cables and sensors of E 813 controller:



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