Technical field

The present disclosure relates to a chimney control assembly for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney and a method for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney. More specifically, the disclosure relates to a chimney control assembly for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney and a method for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney as defined in the introductory parts of claim 1 and claim 16.

Background art

A problem with the solutions of the prior art is that a chimney fan is arranged to increase the draft continuously or at startup of a furnace in a heating device, and since there are a variety of heating devices, of chimneys and of fan products, and the fact that a furnace not necessarily produce best output in relation to heating efficiency and pollution at a maximum draft output delivered by an installed fan. Specifically problematic is this when it comes to particle emissions. It is a problem to provide for optimal heating efficiency and the least amount of pollution/particles to be emitted. Even if there is a timer installed on the fan, it is a problem to find an optimal relationship between particle emission, draft and heat at any time, and the problem increases when installing heating devices and connect those to old chimneys of unknown dimension and status.

Maintaining optimal draft in a heated chimney is also a challenge, and when inhabitants continuously alter the content of the fuel in the furnace it is a problem to optimize the settings of the fan. There is no relation between high draft and efficiency and low particle emissions of a combustion process, specifically not in the case where the fuel is firewood or coal.

The industry has lately provided temperature sensors for regulating fans installed in the exhaust path for mitigating problems with optimized use of the fan to provide optimal draft conditions. When increasing the draft in a fireplace connected to a chimney, the inflow of air to the room where the fireplace is located increases. This adds to the problems that may arise from setting the draft too high; to high emission, to high temperature, to high inflow of cold air to the room, the latter lowering the heating efficiency of the fire operation.

It is an object of the present disclosure to mitigate, alleviate or eliminate one or more of the above-identified deficiencies and disadvantages in the prior art and solve at least the above mentioned problem. Thus it is in present disclosure explained how the novel features of using one or more sensors for a variety of measurements and detection of user actions and controlling a fan and an optional ventilation unit for dynamically adjusting the pressure in the chimney for optimal individual combustion cycles for a fireplace in question. According to a first aspect there is provided a chimney control assembly for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney, comprising: a fuel burning heating devices comprising a combustion air inlet, a chimney comprising a hollow interior, wherein the fuel burning heating device having an exhaust gas outlet connected to the interior of the chimney via an exhaust inlet arranged in the lower portion of the chimney, and the assembly further comprising: two or more sensors, a top mounted fan, and a controller, wherein the controller comprise: a set of parameters reflecting the specified pressure requirements of the fuel burning heating device, input connected to, for reading, the one or more sensors, and output connected to, for controlling, the top mounted fan such that the pressure requirements of the fuel burning heating device 1 can be achieved.

It has been discovered that using the pressure measurements in the chimney, and/or in the fuel burning device/exhaust gas outlet, to regulate the top mounted fan improves the control over the draft considerably compared to fans controlled by temperature and temperature changes.

It is an option to connect more than one fireplace to a chimney, bearing in mind that this complicates the optimization process, and specifically if the fireplaces have different specified pressure requirements of the fuel burning heating device.

Using two or more sensors to provide input data for the controller enables a variety of data to be considered for controlling the fan and draft, the fan being mounted at, close to, or in the upper portion of the chimney, or at least above the uppermost exhaust inlet from a heating device. The goal is to provide a device and method that will optimize the draft according to the vendors pressure requirements of the individual fuel burning heating device independent on fan vendor or chimney type, size or status.

According to some embodiments, the two or more sensors comprise at least one thermocouple sensor at the outlet of exhaust gases from the one or more heating devices.

A furnace burns at different temperatures, and each burning material has different ideal burning temperature at which the pollution/particle emission is lowest. Thus, adding a temperature sensor close to the furnace will enable the controller to adjust fan to optimize the negative pressure in the chimney and the burning sequence continuously, and thus optimize the temperature of the exhaust gases. Each fireplace will have individual emission profiles related to negative pressure, temperature and material to be used for fuel.

According to some embodiments, the two or more sensors comprise at least one pressure sensor for measuring the pressure in the chimney.

The temperature is an indication on how clean the individual furnace may burn, and when a fan is operating at the top of the chimney the negative pressure inside the chimney may indicate the volume of air that may be drawn through the furnace in the burning process. The sensors enables the controller to optimize the action of the fan, and adjusting the negative pressure inside the chimney and furnace temperature in accordance with a preset burning phase setting and the fireplace vendor parameter settings.

According to some embodiments, each of the fuel burning heating devices may comprise a furnace door for accessing and feeding a furnace inside the heating device, and a furnace door opening sensor for detection of the furnace door open/close status.

According to some embodiments, each of the fuel burning heating devices may comprise a combustion air inlet which may comprise a sensor for detection of the furnace combustion air inlet pressure/flow/mass flow.

When opening the furnace door to inspect the furnace, and/or to feed more fuel, for example dried firewood, this action of opening the door is a critical maneuver considering the negative pressure inside the chimney, and the draft through the fireplace. Additionally the state of the furnace is directly affected by the open/close position of the door. It is also right to assume that when the door is opened it is for adding more fuel to the furnace, and if this is the case, the furnace enters into a new burning phase. In the latter event, the door sensor may thus be an indication that the burning phase is changing. According to some embodiments, a ventilation unit is arranged to provide a controllable cross section opening of a duct between the outside of the chimney and the inside of the chimney, and the ventilation unit is arranged at a point below the exhaust inlet from the fuel burning heating device for increasing the pressure inside the chimney when top mounted fan is not operating, and the pressure in the chimney is below the specified pressure requirements of the fuel burning heating device.

In combination with the above sensors and controller arrangements, it may be advantageous to be able to enable the pipe configuration comprise additional means for altering the pressure status along the inside of the chimney. This may be achieved by providing an additional air inlet through a controllable duct, opening and closing a conduit between the lower portion of the chimney and the ambient air, the conduit then being arranged below the exhaust inlet from the fuel burning heating device. As an alternative the conduit may be coupled to a gas/air supply at a higher pressure than inside the chimney. This will add a further dimension to the controllers ability to quickly adapt the pressure inside the chimney on a very short response time. Thus, it may be advantageous to combine the alteration of the fan operation speed and the controllable duct state.

According to some embodiments, the top mounted fan is arranged in the upper portion of the chimney interior to provide a controllable suction effect in the chimney interior relative the pressure outside on the peripheral side of the fan.

According to some embodiments, the controller is provided with controlling schemes individually adapted a furnace operation phase of the fuel burning heating source in the heating device.

Thus it is possible to easy and quickly modify the controlling schemes according to vendor recommendation both for the product type of fuel burning heating devices and of the chimney properties.

According to some embodiments, the furnace operation phase of the fuel burning heating source is one of: Lighting a fire, Stand by, Boost, Normal operation, Burnout, and Tuning.

These are examples, and may certainly be more specific, and is recognized for its requirements to specific optimal pressure and draft settings for the fuel burning heating device. According to some embodiments, the controlling schemes for each furnace operation phase comprise an activation condition defined by readings above/below preset thresholds of the one or more sensors.

According to some embodiments, the controller is provided with a timer unit for timing the controlling schemes furnace operation phases.

The timer is used to provide delays and predefined timing for pressure and/or draft increase, and other.

According to some embodiments, the timer unit comprises individual controlling timing schemes for each transition between furnace operation phases.

According to some embodiments, the chimney comprises one or more sensors for measuring: particles, CO, 02, CO2, flow, and mass flow.

According to some embodiments, each furnace operation phase is associated with a pressure and particle/CO/O2/CO2 emission rate relationship established individually for the chimney and the fuel burning heating device configuration.

According to some embodiments, the one or more thermocouple sensors are arranged in one or more of: a duct arranged between the heating device and the chimney interior, and in the lower interior portion of the chimney interior, and the one or more thermocouple sensors are connected to the controller.

It is considered that the closer the thermocouple sensor sits the furnace, the better control it is possible to facilitate, although a sensible lookup table may fairly quickly be defined by running a few burning sequences, and program the controller according to the findings. This process may also advantageously be including a training scenario for a deep learning actions, and provision of a trained Al (Artificial Intelligence) module to define the correct setting of the assembly.

According to some embodiments, the controller controls the ventilation unit and/or the top mounted fan to establish a pressure profile optimized for heating efficiency and/or emission of particles/CO/O2/CO2 of the fuel burning heating source.

According to a second aspect there is provided a method for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney, the method comprising the steps: providing a chimney control assembly according to the first aspect, configuring the controller with a set of predefined configuration parameters optimized for a fuel burning heating device, starting a fire in the fuel burning heating device, increasing the draft in the fire startup phase by increasing the speed of the top mounted fan for shortening the ignition time and quickly reaching the operating temperature of the heating source, reading the thermocouple sensor and the at least one pressure sensor and regulating the draft induced by the top mounted fan to maintain required pressure and/or temperature.

According to some embodiments, the method further comprises the steps: when the furnace door sensor detects that the furnace door is opened:

- increasing the chimney draft by increasing the speed of the top mounted fan, and thereby eliminating of the backdraft-effect when opening the furnace door.

Effects and features of the second aspect are to a large extent analogous to those described above in connection with the first aspect. Embodiments mentioned in relation to the first aspect are largely compatible with the second aspect.

The present disclosure will become apparent from the detailed description given below. The detailed description and specific examples disclose preferred embodiments of the disclosure by way of illustration only. Those skilled in the art understand from guidance in the detailed description that changes and modifications may be made within the scope of the disclosure.

Hence, it is to be understood that the herein disclosed disclosure is not limited to the particular component parts of the device described or steps of the methods described since such device and method may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only, and is not intended to be limiting. It should be noted that, as used in the specification and the appended claim, the articles "a", "an", "the", and "said" are intended to mean that there are one or more of the elements unless the context explicitly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, and the like. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.

Terminology The term "top mounted" is to be interpreted to at least encompass: mounted at, close to, or in the upper portion of the chimney, or at least above the uppermost exhaust inlet from a heating device.

The term "negative pressure" is used to denote a pressure state for example inside the chimney that is lower than the ambient pressure outside the fireplace and/or the chimney outlet, and is a result of ho air rising inside the chimney, and/or a fan mounted in the chimney pulling air/gas up and out of the chimney.

Brief of the

The above objects, as well as additional objects, features and advantages of the present disclosure, will be more fully appreciated by reference to the following illustrative and non-limiting detailed description of example embodiments of the present disclosure, when taken in conjunction with the accompanying drawings.

Figure 1 shows a principle drawing of a fuel burning heating device coupled to a chimney and comprising a chimney control assembly for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney according to an embodiment of the present disclosure.

Figure 2A shows a block diagram of the control assembly for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney according to an embodiment of the present disclosure connected to a cloud/remote service provider.

Figure 2B show a block diagram of one embodiment of a fuel burning heating device according to an embodiment of the present disclosure

Figure 3A shows a diagram visualizing pressure/time readings from a test run using 6 pressure sensors.

Figure 3B presents a table comprising time/temperature readings from the positions of sensor 1-5 of the test run described in figure 3A.

Figure 4 shows a flow diagram illustrating one embodiment of controlling a complete fireplace burning session as discussed in present disclosure Detailed description

The present disclosure will now be described with reference to the accompanying drawings, in which preferred example embodiments of the disclosure are shown. The disclosure may, however, be embodied in other forms and should not be construed as limited to the herein disclosed embodiments. The disclosed embodiments are provided to fully convey the scope of the disclosure to the skilled person.

Figure 1 shows a fuel burning heating device coupled to a chimney and comprising a chimney control assembly for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney according to an embodiment of the present disclosure. However, in the illustrated test setup there are a plurality of sensors arranged along the chimney and heating device. In a practical real life implementation, there sensor arrangement probably will be less, and as discussed below for the test run an initial fire sequence may be sufficient to establish that it may be enough for one or two pressure sensors to provide the required input for analysis and find the optimal draft and pressure condition for a specific heating device. Thus, the implementation of the assembly of present disclosure may be custom fitted to install sensors at most convenient locations along the draft path of the heating device and chimney.

It is further described various embodiments wherein one heating device 1 is provided with a chimney 2, and a controller 5 and a top mounted fan 4 as illustrated in the figures. It shall be understood that, although not optimal, two or more heating devices 1 may be arranged and connected to the same chimney 2 (not shown). Typically where there are more floors/levels in a building and a heating device 1 in each floor/level is connected to the same chimney 2. Thus the controller 5 may receive input from sensors arranged in the chimney, and in the vicinity of each or some of the heating devices 1 coupled to the chimney 2. The controller logic/SW may then be provided with computing resource able to find a best negative pressure characteristics inside the chimney 2 to optimize the draft and furnace operation phase in the one, or more, or most of or all of the coupled heating devices 1.

The first aspect of this disclosure shows a chimney control assembly for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney, comprising: a fuel burning heating device 1, a chimney 2 comprising a hollow interior, wherein the fuel burning heating device 1 having an exhaust gas outlet 6 connected to the interior of the chimney via an exhaust inlet 7 arranged in the lower portion of the chimney 2, and the assembly further comprising: two or more sensors 11,12,13,14,15,16, a top mounted fan 4, and a controller 5, wherein the controller comprise: a set of parameters reflecting the specified pressure requirements of the fuel burning heating device 1, input connected to, for reading, the one or more sensors 11,12,13,14,15,16, and output connected to, for controlling, the top mounted fan 4 such that the pressure requirements of the fuel burning heating device 1 can be achieved.

It has been discovered that using the pressure measurements in the chimney, and/or in the fuel burning device/exhaust gas outlet, to regulate the top mounted fan improves the control over the draft considerably compared to fans controlled by temperature and temperature changes. Using pressure alone, or in combination with other sensor input, provides the ability to quickly react to pressure changes, and to optimize the draft/negative pressure in the chimney imposed by the fan speed.

One example where a pressure driven fan has been shown to excel over a temperature driven fan is for example when a door in the fuel burning heating device 1 is opened, and the inrush of cold air instantly changes the negative pressure conditions in the chimney. Since the temperature and the temperature sensor will be a lot slower in responding to the changed pressure conditions than the pressure sensor(s), the draft may be much more quickly set to compensate for the changed pressure conditions when driven by pressure sensors rather than temperature sensors.

The set of parameters reflecting the specified pressure requirements of the fuel burning heating device is individually specified by the vendor of the fuel burning heating device. The parameters may define one or more of but not limited to: exhaust air temperature, negative pressure , air flow (draft), parameters for one or more burning phases, chimney characteristics (cross section and/or length), fuel type, and other.

The controller is programmed/selected for the specific fireplace arranged and connected to the chimney upon installation, and the parameters should be chosen as close to the vendors settings as possible.

The sensors 11,12,13,14,15,16 provides data sampled from the exhaust path and chimney from the fuel burning heating device 1 and/or bottom of the chimney 2 to the top mounted fan 4, the top mounted fan4 being mounted at, close to, or in the upper portion of the chimney, or at least above the uppermost exhaust inlet from a heating device, and the controller reading the sensor data and processing these for optimizing the furnace (98) operation phase.

The two or more sensors 11,12,13,14,15,16 may comprise at least one thermocouple sensor 13 at the outlet of exhaust gases from the heating device, and/or at least one pressure sensor 12,14,15 for measuring the pressure in the chimney 2.

Thus, the controller may receive data for instant pressure measurement from the internal of the chimney 2, and typically the controller comprise an ambient pressure sensor 18 for measuring ambient pressure outside the chimney 2, and comparing the sensor readings outside and inside the chimney 2 enables the controller to control negative pressure in the chimney and the draft through the fuel burning heating device 1 to control the furnace 98 to optimize efficiency of the heating process and operation phase according to the vendor specific requirements.

In an alternative embodiment wherein the chimney is part of a more complex exhaust system and/or the chimney outlet is not leading to the ambient air, the controller may substitute the reading from an ambient pressure sensor 18 with a preset pressure value, or a reading from a further pressure sensor on the far side of the chimney or the far side of the fan, or in a next exhaust system portion.

By facilitating an initial burning sequence of the furnace 98 inside a fuel burning heating device 1, as exemplified in figure 3A and 3B for an individual heating device 1 and chimney 2, a relation between pressure and temperature may be established for each operation phase, and used to set thresholds and levels for the top mounted fan 4 operation. Such as for example when the pressure change due to a furnace door 20 is opened or the operation phase change, the top mounted fan 4 may be controlled to mitigate such pressure change. If the furnace 98 burns too fierce the controller may slow or stop the fan to decrease pressure inside the chimney 2.

When the fuel burning heating device 1 further comprises a furnace door 20 for accessing and feeding a furnace inside the heating device 1, and a furnace door opening sensor 17 for detection of the furnace door 20 open/close status.

The furnace door opening sensor 17 may feed the controller 5 with information when the door 20 is opened, and this may signal that the negative pressure change inside the chimney 2 within short. Typically the opening of the door will also signal that additional fuel such as firewood may be added to the furnace. The controller may upon reading the signal from the door opening sensor 17 change the fan 4 operation speed level. In one embodiment the controller may activate a timer 50 which will be used for controlling the duration of the changed fan 4 operation speed. In one example the fan speed change may be delayed 2 seconds and fan speed may then be ramped up/down during a second time period, for example 3 seconds, to reach fan speed setting for the specific operation mode. The new speed may then be maintained until a new operation mode is detected, or the set duration ends, and previous or new speed is set.

The controller 5 may further, as illustrated in the block diagram in figure 2B, comprise a communication module 51 provided for communicating sensor data and computations to a remote computer device 70, such as a cloud server program 70. The communication may be organized to be sent in batches, and a local storage device 52 may be provided to store sensor data and computations made by the controller 5. The remote computer 70 may also be a smartphone or similar. The communication medium 60, 60' may be provided over any adequate wired and/or wireless communication protocol, such as a cloud network, alone or in combination, for example, but not limited by: WAN, LAN, Wi-Fi, Bluetooth, NFC, GSM, GPRS, UMTS, HSPA, CDMA and others. In any implementation the sensors themselves may be set up to communicate directly with remote services as illustrated in figure 2A. One such may be an overheating alarm sensor arranged to signal directly to for example a fire department, or a service organization services.

A ventilation unit 3 may be comprised for providing a controllable cross section opening of a duct between the outside of the chimney and the inside of the chimney 2, and the ventilation unit 3 may be arranged at a point below the exhaust inlet 7 from the fuel burning heating device 1 for increasing the pressure inside the chimney 2 when top mounted fan 4 is not operating, and the negative pressure in the chimney is higher the specified pressure requirements of the fuel burning heating device 1.

Thus using the ventilation duct 3 for facilitating a quick pressure change when the draft is becoming too high, and/or the draft into the furnace is too high. Typically a fierce burning furnace creates a self-amplifying draft and increasing negative pressure inside the chimney 2. This may happen even if the fan is at a standstill. Being able to mitigate the too high negative pressure inside the chimney then may be achieved by increasing/providing an opening through the ventilation duct 3. The opening feature in the ventilation duct 3 may be an analogue variable opening control, or a stepwise opening device, or a digital open-close feature. The ventilation duct opening control typically is controlled by the controller 5. The top mounted fan 4 may advantageously be arranged in the upper portion of the chimney 2 interior to provide a controllable suction effect in the chimney interior relative the ambient outside, or preset, or readings from other sensors, pressure. Alternatively the fan may be arranged in a lower portion of the chimney. When arranged in the upper portion of the chimney 2 it is possible to use the fan to control the pressure along the complete exhaust path 99 inside the heating device 1 and chimney 2.

The controller 5 may be provided with controlling schemes individually adapted to a furnace 98 operation phase of the fuel burning heating source in the heating device 1. The initial test run in the initial setup fire sequence may be used to establish and configure the controller 5, and comprise the various pressure thresholds that may apply for controlling and activating/disabling the top mounted fan 4 and/or the ventilation duct 3. For known chimney configurations and heating devices the controller threshold configuration may be preset before installation, and the test run may be skipped.

The controller 5, the fan 4, and the sensors 11, 12, 13, 14, 15, 16, 16' may be provided in a retrofit format for mounting in existing fireplace and chimneys. Typically the sensors then are of a wireless type.

The furnace operation phase of the fuel burning heating source may be, but is not limited to, one of: Lighting a fire, Stand by, Boost, Normal operation, Burnout, and Tuning.

Examples for setup of the controller is illustrated in table below.

Table 1 : Controller operation phase activation condition configuration

Pressure sensor may provide input to the controller such that processing unit in controller 5 may establish proper fan 4 and/or ventilation unit 3 operation state, such as fan speed or ventilation opening.

The flow diagram of figure 4 may illustrate one embodiment of controlling a complete fireplace burning session as discussed in present disclosure.

The controlling schemes for each furnace operation phase may comprise an activation condition defined by readings above/below preset thresholds of the one or more sensors 11,12,13,14,15,16, as illustrated in Table 1 above.

The controller 5 may comprise a timer unit 50 for timing the controlling schemes furnace 98 operation phases.

The timer unit 50 the chimney may further comprise individual controlling timing schemes for each transition between furnace operation phases.

The timer feature may further be used to ramp up/down fan 4 and/or ventilation unit 3 operation state, such as fan speed or ventilation opening during any furnace operation phase.

The chimney may further comprise one or more particle/CO/O2/CO2 sensors 16, which may be used for additional analysis by the controller. The particle/CO/O2/CO2 sensors may be used to adjust fan 4 and/or ventilation unit 3 operation state, such as fan speed or ventilation opening during any furnace operation phase independent on pressure and temperature readings. The particle/CO/O2/CO2 sensor 16 data may then under certain operation conditions override the preset configuration of the controller. Typically may using different fuel during a fire sequence require alterations to preset configuration to optimize efficiency and pollution.

Each furnace operation phase may be associated with a pressure and particle/CO/O2/CO2 emission rate relationship established individually for each chimney 2 and fuel burning heating device 1 configuration. Typically any vendor may provide a preset controller configuration for any known chimney product, heating device, chimney length, and sensor arrangement. In one embodiment the fuel burning heating device 1 comprises a sensor 16' for detection of the furnace combustion air inlet pressure/flow/mass flow. The furnace combustion air inlet pressure/flow/mass flow sensor 16' may be connected to the controller 5, and the controller 5 may further comprise the ability to adjust the combustion air inlet in order to optimize draft through the fuel burning heating device 1 and the negative pressure in the chimney.

A thermocouple sensor 13 may be arranged in a duct 8 which may be arranged between the heating device 1 and the chimney 2 interior, and/or in the lower interior portion of the chimney 2 interior, and connected to the controller 5. Temperature readings may also be provided by a temperature sensor provided in the fan unit 4. The controller may further comprise an ambient air temperature sensor, and use this to establish relative temperature difference between the exhaust and ambient temperature. Thus any senor data established from the chimney or heating device may be compared to corresponding ambient sensor readings to establish differences to ambient data, and this difference, Delta, is used to define current configuration of fan 4 and/or ventilation unit 3 operation state, such as fan speed or ventilation opening.

The sensors may be wired/wireless sensors, communicating with the controller over a wired/wireless communication channel. Typically the wireless sensors are powered by batteries, or when passive sensors they may be powered by the received wireless signal from teh controller. One example of such unpowered wireless sensors may be an RFID temperature sensor.

Although not shown in the figures the controller, fan, and valves are typically powered by a power connection to the power grid, or alternatively powered by a battery or similar.

When the chimney is part of a more complex exhaust system and/or the chimney outlet is not leading to the ambient air, the controller may substitute the temperature readings reading from the thermocouple sensor 13 with a preset temperature value, or a reading from a further temperature sensor on the far side of the chimney or the far side of the fan, or in the next exhaust system portion.

The controller 5 may control the ventilation unit 3 and/or the top mounted fan 4 to establish a pressure profile optimized for heating efficiency and/or emission of particles/CO/O2/CO2 of the fuel burning heating source 1. The second aspect of this disclosure shows a method for minimizing particle emission in a combustion process in a fuel burning heating device connected to a chimney, the method comprising the steps: providing a chimney control assembly according to the first aspect to the first aspect, configuring the controller with a set of predefined configuration parameters optimized for a fuel burning heating device, starting a fire in the fuel burning heating device 1, increasing the draft in the fire startup phase by increasing the speed of the top mounted fan 4 for shortening the ignition time and quickly reaching the operating temperature of the heating source 1, reading the thermocouple sensor 13 and the at least one pressure sensor 12,14,15 and regulating the draft induced by the top mounted fan 4 to maintain required pressure and/or temperature.

In a user scenario setup the various aspects of the invention according to present disclosure was setup with pressure sensors along the chimney, with a first sensor 1 at the bottom of the chimney, a second sensor 2 a bit closer to the conduit from the firing place entering the chimney, a third sensor 3 inside the conduit from the fireplace, and a fourth and fifth sensor 4 and 5 along the inside of the chimney, measuring and monitoring the firing sequences then gave the following sequence of events and governance of the fan, as seen in the pressure graph of figure 3A and the temperature readings in figure 3B, at the top of the chimney. The timeline is added to synchronize the table values to the graphs of figure 3A and figure 3B. The example shows:

At 11:39 The wood stove was lit, with a pipe-fan at the top of the pipe, active.

At 11:46 The pipe-fan was stopped and removed, to not interfere with the measurements.

At 11:48 The oven door was opened to supply more wood, and this is clearly seen in the measurements.

The graph drops down, meaning the pressure difference is less, meaning closer to the ambient pressure.

The surface temperature of the pipe was measured at 5 locations (close to the first 5 sensors), using an IR temperature reader. All temperature readings are in degrees Celsius.

At 12:12 the door was open for a few seconds to refill wood.

At 12:15 the oven air flow was trimmed

Observe!

At 12:17 the regulator was enabled (removed the blockage) and this is clearly seen in the graphs! The suction in the pipe fell significantly.

At 12:45 the regulator was again blocked (closed) and we clearly see the suction in the pipe increased.

At 13:02 the pipe fan at the top, was mounted and started, and we clearly see the suction effect.

At 13:35 the fan was brought to full speed.

At 13:37 the fan was shut off.

At 13:40 we stopped the test and sensors were shut off

A further method may be provided to comprises the initial steps: when the furnace door sensor 17 detects that the furnace door 20 is opened:

- wait a preset timer period, then

- increasing the chimney draft by increasing the speed of the top mounted fan 4, for eliminating the backdraft-effect when opening the furnace door 20.

The method may further comprise the steps: for each phase comprising one of:

Lighting a fire,

Stand by,

Boost,

Normal operation,

Burnout, and

Tuning; the controller reading one or more of pressure sensor (12, 14, 15), furnace door sensor (17), and thermocouple sensor (13), and the controller regulating the top mounted fan (4) to maintain furnace (98) operation phase, or to transit to predefined next phase, and/or the controller regulating the ventilation unit (3) to maintain furnace (98) operation phase, or to transit to predefined next phase

The person skilled in the art realizes that the present disclosure is not limited to the preferred embodiments described above. The person skilled in the art further realizes that modifications and variations are possible within the scope of the appended claims. Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed disclosure, from a study of the drawings, the disclosure, and the appended claims.