Boiler room ventilation - a key element of effective and ecological combustion

Boiler room ventilation - a key element of effective and ecological combustion

Wood has been very popular as a fuel in Poland for centuries, being widely used in many households. However, to achieve optimal results when burning wood, it is necessary to ensure proper air supply to the boiler room. Why is it so important? How to properly supply air to the boiler room? What are the consequences of lack of ventilation? Does the air supply affect the efficiency of the boiler? Let's take a closer look!

How does the air supply affect the boiler room?

Automatic heating boilers equipped with blow-in or exhaust fans require adequate supply of fresh air to the boiler room. Why is it so important? Let's imagine a situation in which we lock a person in a hermetic room, without the possibility of opening the windows and doors. Every breath a person takes takes in fresh air from the room. After a while, the lack of oxygen to breathe can lead to nausea and weakness. Fans behave similarly. A person needs about 30 m3/h of fresh air to breathe, while a fan provides an air flow almost ten times greater.

What happens when there is no air supply in the boiler room?

It may seem that air supply to the boiler room is not necessary in the case of eco-pea coal or pellet boilers. However, this is a false belief. In order for the burner to be able to supply the right amount of oxygen to the furnace, it is necessary to equip the boiler room with fresh air. When such air is not available, the efficiency of the fan decreases by about 60%, even though it is still spinning and operating. This can be illustrated by an example:

In the case of low fan power settings, a 60% decrease in efficiency may lead to insufficient air to properly and, above all, safely burn solid fuel. If there is a lack of air in the boiler room, the efficiency of the fan drops to as much as 12%. Such a reduction in efficiency can lead to incorrect fuel combustion, overheating of the pellet furnace, increased fuel consumption and accumulation of soot in the boiler, which we wrote about in the article: Boilers for solid fuels: pellets, wood, coal - how to deal with them?

As can be seen from the example, not providing fresh air can lead to unfavorable situations. Sometimes the boiler room can be so polluted with soot that a service technician is required to come to the site to make repairs. An example of such a case is the visit of one of our service technicians who

came across such a view while working for one of the clients with a pellet boiler:

Tarred pellet boiler exchanger. (oryginal source)

boiler covered with soot as a result of lack of air supply to the boiler room.

The boiler room was located in a newly built single-family house with an area of approximately 120 m2 and was located inside the building. The door leading to the boiler room was airtight, and the only source of ventilation was a closed window. After diagnosing the problem, the service technician recommended air supply, and the window in the boiler room was temporarily opened. The problem with soot in the boiler was solved, despite the client's initial doubts, who immediately after seeing the effect with the window open decided to blow fresh air into the boiler room. After a few weeks of operation with ventilation, the device looked much better. The walls of the boiler were covered with white dust. The combustion was seen to be full and clean.

How to install the air supply to the boiler room?

The method of ensuring air supply to the boiler room has already been described. Please note that this is not only necessary for the proper functioning of the boiler, but also a legally regulated requirement. So how to properly install the air vent so that it does its job? There are two solutions.

The first and most commonly used solution is to drill a ventilation hole at a height of about 30 cm from the floor (the so-called air inlet). The air inlet itself should have a cross-sectional area of at least 200 m2. the maximum height of the air supply grille is 1 meter from the floor. Many customers do it themselves, using ready-made kits available in construction stores:

Ready air supply set by DARCO (source internet)

The diffuser inlet must always remain uncovered - it must not be covered or covered, otherwise fresh air will not be able to reach the boiler room. The use of this solution will allow air to be supplied to the room with the boiler. The air inlet itself should be located at a height of up to 50 cm from the floor - otherwise fresh air from the boiler room may be sucked in not by the boiler fan, but by the exhaust system in the boiler room.

Mounted air supply kit in the wall. 1 - internal element, 2 - external air intake

The previously described solution is not suitable for basements due to the installation height relative to the floor. If we used this solution in the basement, the inlet would be closer to the ceiling of the boiler room than to the floor. Therefore, in this case, an alternative solution, called "zetka", is used:

Properly made air supply to the solid fuel boiler room. The so-called zeta.

Zetka will allow air to be supplied to the boiler at the desired height and ensure proper air circulation in the boiler room. It will also ensure proper fuel combustion and the right temperature in the room. Summary of air supply to the boiler room!

Heating devices with an open combustion chamber, equipped with automation, require appropriate operating conditions to work properly. In addition to fuel, settings on the controller, conductivity of the chimney and condition of the boiler, one of the most important aspects is the proper supply of fresh air to the boiler room. It is also one of the warranty conditions for the devices to work according to their specifications. Properly performed air supply to the boiler room means not only the efficient operation of the device, but also the satisfaction of the user with its proper functioning.