What to do if the hood in the bathroom and toilet does not work well: possible malfunctions and the best ways to solve the problem

When designing houses, the mandatory presence of ventilation in the utility rooms, the kitchen and, of course, in the bathroom and toilet is taken into account. This is necessary to ensure natural air exchange in these rooms.

As for the bathroom and toilet, it is thanks to ventilation that normal air humidity is maintained, the exhaust air is evacuated in a timely manner and replaced with clean air.

If the hood in the bathroom and toilet does not work well, then air stagnation is inevitable, which in the near future will result in the appearance of mold and mildew, and will also negatively affect the decoration of these rooms. An extremely unpleasant situation, isn't it? But what to do in this case and how to prevent it?

In this article, we will talk about the causes of ventilation problems in the bathroom and toilet, as well as analyze the best ways to solve them.

How is the ventilation of the bathroom and toilet arranged?

Ventilation is, first of all, a whole system consisting of air ducts and shafts. When designing it in private or an apartment building, stable performance is calculated with correct operation.

The ventilation device includes:

• Ventilation duct (ventilation shaft), which is a combination of one-piece straight air ducts and vertical shafts. The shaft and channel can be either round or square. A prerequisite for stable air movement is their purity and integrity. There are also horizontal ventilation ducts, but their length should not exceed two meters, otherwise the air movement will become difficult.
• Ventilation outlet - this is a hole in the wall of a bathroom or toilet, which is connected to the ventilation duct. The size of the opening of the ventilation outlet does not necessarily correspond to the cross-section of the duct and is calculated based on the creation of the maximum possible volume of air throughput.
• Ventilation grill - it is necessary to protect the ventilation duct from the ingress of debris into it, as well as from possible penetration of insects and rodents into the room. Made of plastic or metal. It has a decorative appearance, since its front part must fit into the interior of the room.

It is worth noting that ventilation can be naturallyth and compulsory. The difference lies in the use of additional devices to mechanically create more thrust.

Additional devices are installed in cases where natural draft does not provide effective ventilation of the room.

Features in the work of ventilation systems

Ventilation of the premises of apartment buildings and houses of the private sector can be ensured by proper arrangement of natural and forced ventilation. Let's consider these two types of systems in more detail.

View # 1 - natural ventilation

Natural ventilation is according to general standards. It is used in all typical apartment buildings.

The principle of operation is based on the law of convection, the essence of which is that due to the difference between the temperature inside the room and the temperature by outside, as well as due to the difference in pressure, which is different on the street and indoors, the air is independently drawn into the ventilation channel.

The force with which the air flow enters the duct is called thrust. The air that has gone into the ventilation makes room for fresh air.

Type # 2 - forced ventilation

The main difference between forced ventilation, as mentioned above, is that additional equipment is used, namely, household fans of various types (axial, duct or radial).

The principle of operation is based on an additional increase in thrust due to the rotation of the blades of these devices. Ventilation equipment with devices is carried out independently.

Forced ventilation in most cases is an independent improvement of natural ventilation. It must be carried out in compliance with the norms (in particular, in terms of fan power), otherwise such an installation may disrupt the natural ventilation system of the room in an apartment building.

Depending on the functions performed, forced ventilation is:

• exhaustwhen the air flow is drawn by a fan into the street;
• inflowwhen the fan, on the contrary, supplies air to the room, and the full ventilation cycle is provided due to the air leaving in a natural way through shafts and ventilation ducts;
• supply and exhaust, when there is a possibility of both forced injection of air into the room and its removal from it.

The existing forced-type supply and exhaust ventilation is used for large rooms when the natural, mutually controlled air movement in the room is not enough.

What kind of ventilation is needed in the bathroom and toilet?

As conceived by the designers, natural ventilation should cope with air circulation on its own. However, natural ventilation is often not provided for the normal circulation of air in a room.

This happens for three reasons:

• with natural ventilation, a constant flow of external air into the room must be ensured - the door must be open, a special inner window must be installed inlet valve into the wall;
• the inner walls of the ventilation ducts become dirty - dust, dirt, debris and cobwebs appear in the ventilation over time and in the absence of cleaning;
• the external ventilation outlets are clogged.

Thus, for the organization of effective ventilation of the toilet and bathroom, it is more expedient to use forced ventilation. It will provide a quick change of air in the room, remove odors and reduce humidity in the shortest possible time.

It is worth noting that to determine the state of ventilation, it is enough to use a sheet of paper or a lighted match, brought to the ventilation grill. When the ventilation system operates optimally, the flame should deflect significantly towards the duct, and the sheet of paper should be attracted to the grate.

If this does not happen, then we can talk about a problem with ventilation. One of the reasons for insufficient draft is lack or weak air flow. What can be a consequence of the tightness of the doors installed in the bathroom / toilet. This obstruction to the intake of fresh air is the reason that the exhaust humid air cannot be drawn out of the room even if the hood is working properly and when the fan.

When choosing and installing exhaust devices, it is necessary to be guided by the main guiding documents: SNiP 41-01-2003 ("Heating, ventilation and air conditioning") and SNiP 2.08.01-89 * ("Residential buildings"), which are updated as of 2019 by making certain changes. In particular, in the bathroom and toilet, an air exchange of at least 25 cubic meters per hour must be ensured. If the bathroom is combined, then at least 50 cubic meters per hour.

The reasons for the poor performance of the hood

Poor operation of the exhaust ventilation cannot be caused only by contamination of ventilation ducts and outlets or the creation of an artificial obstacle to the occurrence of draft.

There are a number of other reasons due to which the hood in the toilet and / or bathroom stops working.

Among them are the following:

1. High outdoor temperature. Air circulation is more efficient during periods of the year when the temperature outside the window drops below +5 degrees.
2. Installation of an axial fan. Due to the design, in the off state, this type of fan interferes with the free flow of air. The motor and blades of the axial fan do not move without electric current.
3. Extraction devices too powerful. Using a fan that is too powerful will disrupt the projected air movement in the entire ventilation system. As a result, the dispersed air does not go out into the street, but enters other premises of the apartment building.
4. Redevelopment and illegal interference with the general ventilation system. As a result of the changes made, the tightness of the ventilation system may be compromised or one of the channels may be blocked altogether. That is why any redevelopment requires approval from government agencies.
5. Incorrect installation of the door to the bathroom or toilet. Usually the problem arises when there are no special ventilation holes in the door leaf (typical for cheap doors) and there is no gap between the floor and the door.
6. The emergence reverse thrust. This problem is typical for the upper floors of apartment buildings due to the build-up of excessive pressure in the ventilation system.

When one of the reasons that affect the normal air circulation appears, the humidity in the bathroom and toilet immediately rises.

By the way, condensate not only signals ventilation problems, but can also cause damage to ventilation equipment. For example, as a result incorrect installation of additional equipment a gap forms between the fan and the draft ceiling of the ventilation system. Due to the cooling of the hot air, condensation forms in this gap, which is partially absorbed and partially flows down. Condensation can damage the fan over time.

We also recommend that you familiarize yourself with the reasons why the cooker hood can not work at all, as well as with ways to eliminate them.

Methods for determining the malfunction of the hood

There should be no bad ventilation in the bathroom. After all, otherwise the level of air humidity rises, which is an indicator the ecological state of the premises. Damp air can make people feel worse, feel stuffiness and heaviness, and is also a cause of exacerbation of chronic diseases.

That is why there is a concept of optimal and permissible humidity in the room, which is indicated in GOST 30494-2011. For a bathroom, the optimal values ​​are 30-45%, permissible up to 60%.

It is possible to prevent the humidity level from rising to critical levels if the hood malfunction is detected in a timely manner and eliminated. Therefore, if you begin to notice that after visiting the bathroom, moisture remains on the walls and mirrors for too long, it is advisable to check the traction force. For this, you can use a sheet of paper (lean it against the ventilation grate) or a lighted match (the flame will deflect towards the grate), which will determine the strength of the exhaust air flow. If it turns out to be too weak, a representative of the management company should be called.

A specialist, using a special air speed meter - an anemometer, will measure the air outflow rate per hour and give an opinion on non-compliance with the standards. He can also determine the air permeability for the entire riser of an apartment building.

It is worth noting that a utility specialist may not identify the problem if it is associated with the use of a neighbor of a fan that is too powerful - during the study of the traction force in the systems, the exhaust device may be switched off.

In winter, you can also check the extractor hood in the bathroom and toilet yourself. To do this, open wide open the window and doors of the room where the ventilation outlet is located. This will accelerate the draft by displacing warm air with cold air. It is enough to attach a sheet of paper to the exhaust grille. If the ventilation system is working properly, it should stick to the grate.

Best ways to solve the problem

Now let's talk about what to do if the hood in the toilet or bathroom does not work. So, the standard and most effective way to solve a problem associated with a ventilation malfunction is to contact to the management company, which must take effective measures to restore normal performance hoods. Their responsibilities include checking cleaning and restoration of ventilation ducts.

They are also obliged to force the tenants of an apartment building, who independently dismantled or changed the ventilation ducts during redevelopment, to restore their original condition.

However, the involvement of a management company is a rather lengthy process.

Therefore, some problems can be solved by yourself:

1. If there is a problem with the "reverse draft" effect, when the air from the hood enters the room, then it can be solved in two ways: either by installing a blower fan, which makes the air pressure in the room stronger, or by installing a decorative grill with check valve into a standard hole for the hood, which will create an obstacle to the penetration of air into the room from the exhaust system.
2. To improve the operation of the hood on the upper floors of an apartment building, an increase in the height of the box with which the ventilation duct ends will help. It is located on the roof of the house and you can increase its length yourself using a corrugated pipe. You can also install deflector, which, under the influence of the wind, will create additional thrust in the system.
3. The problem with the hood in a private house can be solved by installing a separate air duct. It will provide an additional flow of air and, therefore, increase the pressure in the room, which will create an air circulation process. A vertical duct with access to the roof will work most effectively.
4. When the hood does not work in one of the rooms, the problem is solved fan installation. Only this installation must be performed in strict accordance with regulatory requirements in order to avoid consequences. Nowadays, it is possible to buy fans equipped with a humidity sensor, a time switch and a motion sensor, which allows them to use them most efficiently while conserving electricity.

It is worth paying close attention to the cleanliness of the decorative ventilation grill. There are cases of dust clogging a special mesh, which is necessary to prevent insects from entering the apartment, as a result of which the air cannot normally go into the ventilation duct.

You also need to regularly clean the fan in the bathroom and toilet, taking into account the manufacturer's recommendations for the care of a particular model.

Conclusions and useful video on the topic

The principle of natural ventilation is shown in detail in this video:

In order to make it more clear how you can clean the ventilation shaft with your own hands, you can watch this video:

This video shows why and how you need to install additional devices for forced ventilation of the bathroom:

The correct operation of the hood in the bathroom and in the toilet is a guarantor, first of all, of the health of residents of an apartment or house. The absence of humidity, dampness and mold, regulation of fresh air in the room depends on the operation of the hood. Dampness negatively affects the interior decoration of premises and can lead to destruction of tiles and the formation of rust on metal surfaces.

If problems are identified with the normal operation of the hood, immediately take corrective measures situations and if you can't solve it yourself, then you need to contact the manager for help company.

Do you still have questions, useful additions or want to share your personal experience in troubleshooting the ventilation system in the bathroom? You can leave your recommendations and other information as a comment to the article in a special form, which is located below.