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Why does the flexible pipe from the feeder on the pellet boiler turn dark?

The flexible pipe will become dark if the flue gases backflow into the fuel feeder. The reason for fumes backflow to the feeder can be insufficient flue draught, lack of boiler room air duct, overfilled and dirty burner or dirty boiler exchanger.

Do I have to have a "Z - aeration" after all, I have a ventilation grille in the flue? Is it not the same?

Air is needed to burn fuel. For every cubic metre of exhaust gas that exits through the flue, a cubic metre of air must enter the boiler room from outside the building. The ventilation grid is the inlet opening of the ventilation exhaust duct. The boiler room must be equipped with an intake system, this is the so-called aeration of the boiler room, that is air intake to the boiler room from outside the building. The intake technological system is usually made in the form of so called "Z".

Why can't the boiler temperature be set lower than 60 degrees.

A solid fuel boiler should operate at a boiler temperature of 65-75 degrees C. The combustion process proceeds properly then, the fuel consumption is the lowest. Boiler temperature that is too low lowers the temperature in the combustion chamber and prevents proper burning of fuel. As a result of improper combustion, harmful gases and dust are emitted into the environment and the boiler quickly becomes dirty, the amount of consumed fuel increases.

When changing fuel (pellets), do I have to reweigh the fuel?

Due to the variety of pellet types, mainly pellet diameter, density, humidity and length, we recommend verifying the fuel feed rate. With extremely different pellets, differences in feeding capacity can reach up to 70%. The most significant difference is in feeder efficiency when changing the diameter of the pellets from 6 to 8 mm.

Is a "Z" necessary? After all, I have a window in the boiler room (what is the diameter of the Z?)

A constant supply of air is needed to burn fuel. The room where the boiler is fitted must be equipped with an air intake system which supplies air from outside the building (this is defined by building law). The supply duct should have a flow area of not less than 200 cm2 (but not less than 5 cm2 per 1 kW boiler output). Inlet ducts in small buildings are usually made in the form of the so-called "Z". The window does not perform the function of air supply (it may be closed - modern windows are tight), the window performs the function of natural lighting of the room

How often should I clean the boiler?

The frequency of cleaning can be determined by observing the operation of the boiler for several weeks and depends on the quantity and quality of the fuel burned. When heating individual flats and houses, due to low fuel consumption, the principle of replenishing the fuel tank once a week is often applied, and burner and boiler cleaning should be performed with the same frequency. For larger boilers where fuel consumption is higher, it is recommended to clean the boiler and burner every time the fuel is loaded into the tank. If the fuel is of lower quality, the frequency of cleaning must be determined individually.

I have a flue with a diameter of less than 150 what to do to make the boiler work properly.

The boiler must be connected to a self-contained flue pipe. The flue duct must have a minimum diameter of 150 mm or a cross-sectional dimension of 140 X 140 mm. The dimensions of the flue duct are in accordance with building law. The correct operation of the boiler is also contingent on other elements resulting from the design of the flue, its quality and tightness The flue should be fitted with thermal insulation and be routed at least 60 cm above the highest edge of the roof. Proper operation of the boiler is also affected by the way it is connected to the flue. The boiler connection to the flue should not be longer than 1.5 m and have maximum two elbows. It is recommended to provide thermal insulation of the flue connection. In the boiler manual (DTR) there is specified minimal flue draught which must be met for the appliance to work properly.

Why does the hopper feeder not feed pellets?

There may be contaminants in the fuel which will cause the fuel feed to stop. Check if there are any large impurities in the feeder pipe - usually paper or foil - which block the fuel feeding. Check the bottom of the fuel tank, where the feeder operates, for dust and small sawdust, but also other contaminants that restrict pellets from entering the feeder's feeding spring. It is also necessary to check the operation of the geared motor and that the screw connecting the spring to the geared motor has not come loose.

I have bought or want to buy a room thermostat ... can I connect it to the Heiztechnik boiler? What can it control?

Any voltage free ON/OF type thermostat can be connected to the boiler automatics. Automatics enables two thermostats to be connected. One can control the operation of the heating system pump, the other one the operation of the valve pump and, depending on the settings and equipment, the operation of the mixing valve.

How do I adjust the boiler after a fuel change?

If you purchase a new batch of fuel and notice changes in the burner operation, check the amount of fuel fed through the main feeder. Due to the variety of pellet types, the amount of fuel fed by the feeder may vary. Checking consists in determining the feeder capacity per time unit, i.e. how many kilograms of pellets the feeder feeds per hour of operation. Determining the feeder output is a simple operation and consists in performing the following actions: Switch the boiler off with the controller from "Boiler off" operation. Disconnect the bottom part of the flexible connector from the burner and direct the outlet towards a specially prepared, by way of illustration empty container, into which pellets will be poured. Next, enter the "Output test" menu, search for "Main feeder" and switch it on. The main feeder starts working, pellets are poured into the prepared container. The feeder will switch off automatically after 10 minutes of operation. Weigh the poured in fuel. Thefigure from the scales is multiplied by 6 (because 6 x 10 min = 60 min = 1 hour). In this way, we have determined the feeder capacity at hourly operation - how many kg of pellets it feeds per hour of operation. Enter the resultant figure into the controller operating parameters as per the scheme: "Service menu", password 3456, "Burner menu", "General", "Feeder capacity". Enter the obtained result in this item. Check if the result was saved. The boiler is automatically configured for proper operation by the automatic functions.

What do I need to buy to control the three mixing valve actuators, the circulation pump and the buffer pump?

By default, the automatics controls one mixing valve servo. In order to extend the system control, the automatics should be equipped with two additional modules.
HT-tronic M-Z2 valve module which controls two mixing valve actuators and HT-tronic M-BC module which controls a circulating pump and a buffer pump.

What power boiler should I buy?

A correctly selected boiler minimises the amount of fuel consumed. At present, in new buildings, energy audits specify the thermal energy demand and the heating capacity of the appliance. If there is no such document and it may not be produced, we can calculate the power of the boiler ourselves. The basic element that needs to be determined is the power demand per m2 of heated surface. The power demand is mainly affected by the thermal insulation of the building (thickness and quality of materials) and the number and quality of doors and windows. The following values of boiler power demand are assumed for individual boiler estimation:

- Energy efficient buildings (very thick insulation, modern doors and windows) - power demand factor 30 - 50W/m2

- Standard buildings (average wall and roof insulation 10-15 cm) - power demand indicator 50 - 80W/m2

- Energy-intensive buildings (no insulation or up to 8 cm) - power demand indicator 80 -120W/m2

- Very energy-intensive buildings (thin walls without insulation) - power demand above 120W/m2 .

Based on the above parameters we qualify our building and determine the indicator of power demand. For example, we have defined our building as a standard building, due to the thickness of insulation the type of doors and windows we choose the demand indicator - 80W/m2, we have a house with a heating area of 140m2 to be heated. Calculation of the boiler capacity: 80W/m2 X 140 M2 = 11 200W. In order to heat a building, a boiler of 11.2 kW is needed and to heat domestic water, the boiler capacity is increased by 3 kW. In order heat the building and DHW a boiler of approx. 15 kW is needed.

Why does my boiler burn so much?

The amount of fuel consumed results from the amount of energy received by the house utility systems. Burning 1 kg of pellets produces approx. 5 kWh of heating energy. When the boiler works to reach the set temperature and shuts down automatically (pellet boilers), the boiler stops consuming fuel. In order to determine the reason for excessive fuel consumption, it is necessary to check the proper operation of the boiler burner and the heating system. The boiler burner should work by modulating its output, adjusting itself to the heating system demand and at the same time ensuring that the preset boiler temperature is reached. It is important that the operation in power modulation mode is as long as possible. The boiler should operate with a preset temperature of 65 - 750C. The boiler achieves an energy efficiency of 90%. It is important to set the operation parameters of the heating system. The heating medium of appropriate temperature should be transferred to individual circuits of the heating system through control elements (e.g. mixing valves) - e.g. floor heating system supply temperature 28 - 32 C, radiator systems 40 - 60 C (most commonly used). Precise regulation of the system supply temperature should result from the heating curve of the automat operating in the weather mode. Room thermostats or thermostatic heads should switch off the power supply when the room temperature is reached. The most frequent causes of excessive fuel consumption are: incorrect temperature setting on mixing valves, thermostats and heads, or failure to install these elements on the system. Excessive fuel consumption results from excessive transfer of heat energy from the system to the heated object - overheating of rooms. The boiler burns a lot, probably because it produces a lot of heat energy, which is taken away by the technological system of the facility.

For what reason it melt my flexible pipe?

The flexible joint is a fuse between the burner and the fuel tank. Its melting proves effective operation before the flame penetrates from the burner to the hopper. The reason for fumes backflow to the feeder can be insufficient flue draught, lack of boiler room air duct, overfilled and dirty burner or dirty boiler exchanger. These causes may combine and accumulate - it is absolutely necessary to remove them, so as not to cause another melting of the connector.

The pellet boiler does not reach the set temperature, what to do.

The boiler does not come up to temperature due to operation at too low an output in relation to the heat consumption of the heating system. The first step is to check whether the heat consumption of the heated facility is correct and whether there are no excessive temperatures in the heated rooms. A parallel action is increasing the boiler capacity. In the controller MENU BURNER settings, in the MAXIMUM POWER function, increase the boiler capacity to an appropriate level which will ensure reaching the pre-set temperature.

Why does the controller display a power interruption alarm, after all there was no power interruption.

The alarm is displayed if the voltage drops below 140V, which is the minimum required voltage for proper operation of the automatic control system. There was no interruption in the supply of electricity, and the voltage drop caused an interruption in the operation of the automatics and was the cause of the message display.