How to choose and install a chimney for a gas water heater

Exhaust pipes for geysers

Features for installation in a private home

If you thought about a chimney at the construction stage of a building, the best choice would be to install a vertical brick shaft, inside of which a steel or asbestos pipe can be located. At the same time, it is important that the gas water heater and the heating system have different shafts for removing smoke.

If the building has already been built, the most suitable chimney option is an insulated steel pipe. It can either be attached to one of the external walls, or installed inside the building through its ceilings and roof.

Other nuances of installing a chimney in a house are the following:

• The material and design of the chimney, as well as the installation location, must comply with current regulations.
• The chimney must be easily accessible so that, if necessary, possible problems can be quickly eliminated.
• When installing a chimney vertically in a house, it is important to prevent a significant deviation of the pipe - it should not deviate more than 1 meter throughout the entire structure.
• The end of the chimney pipe should protrude at least 40-50 cm above the roof.

Exhaust bends for geysers (elbow)

Gas flange for geysers

Regulatory requirements

According to the table of definitions NPB 252-98, the exhaust pipe for a gas water heater is the connecting pipe for the smoke exhaust pipe of the device and the smoke duct. Accordingly, it transports gas combustion products and must meet the requirements for chimneys. Failure to comply with them can lead to gas pollution in the room and carbon monoxide poisoning.

All requirements for chimneys are set out in the following regulatory documents:

• NPB 252–98;
• Rules for the production of pipe and furnace works VDPO;
• SP 42-101-2003, Appendix G
• SP 60.13330.2012, which is an updated version of SNiP 41-01-2003 (replacing SNiP 2.04.05–91).

The main provisions that directly relate to smoke removal from household gas water heaters boil down to the following points:

• The cross-sectional area of ​​the exhaust pipe is taken to be no less than the cross-section of the outlet pipe of the unit;
• It is necessary to ensure complete tightness of the chimney, its resistance to corrosion and high temperatures up to 200 °C;
• Laying connecting pipes through living rooms is prohibited;
• The vertical section of the exhaust pipe at the outlet of the column must be 500 mm high, in some cases it can be reduced to 250 mm;
• Connecting pipes should be up to 3 m long in new buildings and up to 6 m in existing ones;
• It is allowed to use no more than 3 turns with a bend radius no less than the diameter;
• The exhaust pipe is installed at a distance from the ceiling or wall made of non-combustible materials of at least 5 cm, if they are combustible or difficult to burn, then at least 25 cm. The distance can be reduced to 10 cm by taking protective measures in accordance with SP 42-101-2003;
• If the connecting pipe for a gas water heater passes through an unheated room, then thermal insulation must be used;
• The exhaust pipe must be laid with a slope of 0.01 or more towards the appliance.

End platform (wall plate) for geysers

Types of pipes for a gas burner

The specialized market offers various models of exhaust pipes for installing a gas water heater in an apartment.

Corrugated pipe

One of the popular equipment options is a corrugation made of aluminum or stainless steel for extracting a gas burner.

• using a corrugated pipe it will be more convenient to lay a gas outlet line, regardless of the complexity of the route, avoiding obstacles;
• it is easy to hide the flexible pipeline in cabinets or decorate the run with removable panels.

Corrugated pipe for a geyser.
Corrugated aluminum pipes for a geyser are characterized by their lightness, attractive price, and ease of installation. A significant disadvantage of the product is the possibility of burning out under conditions of high temperature loads. For fire safety purposes, experts recommend using stainless steel corrugation, despite the relative high cost of the product. The big disadvantage of the material is the difficulty of maintenance: it requires some effort to keep the flue pipe for the chimney of a gas water heater clean.

Coaxial ducts

The device is a double-circuit system in the form of a chimney pipeline inside a sleeve. The coaxial design combines the removal of combustion products and air injection from the street. Here two streams move towards each other along their channels. In this case, the outer cavity - the gap between the two walls of the double-circuit purlin - delivers air from the street, sucked in by the fan, into the combustion chamber. Exhaust gases exit the gas column through the internal pipe, heading to the top point of the line.

The key advantage of a coaxial air duct is the increase in the efficiency of a gas water heating device, since as a result of heat exchange, the air reaches the burner heated.

Stainless steel

Stainless steel pipes are considered an ideal air duct option for a geyser in an apartment. Among the advantages of the product are the following:

• durability of the material;
• corrosion resistance;
• resistance to deformation;
• there is no risk of burning through the steel pipe for the gas water heater;
• aesthetic appearance;
• the design fits harmoniously into the interior design of any style;
• The exterior of the stainless steel pipeline is easy to keep clean.

Among the disadvantages of stainless steel pipes for geysers, they note the relative high cost of the product compared to models made from other materials.

Cink Steel

Chimney pipes made of galvanized steel, like purlins made of stainless steel, can be insulated - sandwich - or ordinary. If you plan to lay a gas vent through an unheated room or a cold attic, it is advisable to use a sandwich structure. In other cases, it is recommended to opt for a conventional galvanized model.

As experts note, it is undesirable to use a galvanized metal pipeline for a gas water heater with a high temperature of exhaust gases. The fact is that there is a risk of dangerous compounds being released when the galvanized air duct is heated too much.

Plug for cleaning the ash pan of a gas water heater

Installation procedure

Installation of an exhaust pipe for a geyser made of any material begins with taking measurements and preparing all the necessary elements. In the case of corrugation, the work procedure is very simple. It is enough to take a pipeline of the required length, put it on the smoke exhaust pipe of the water heater and clamp it with a clamp. The free end is inserted into a decorative ring and fixed in the opening of the smoke channel. The main thing here is to ensure that the diameter of the corrugated pipe matches the size of the outlet hole of the column.

For all other materials, you need to prepare the required number of straight and rotary elements that will be inserted into each other, forming the desired chimney configuration according to the principle of a designer. Rotation angles are standard or made individually for specific sizes.

During assembly, ensure maximum tightness of connections. The entry of one element into another must be at least half the diameter. For better sealing, heat-resistant sealant is used. The joints are fastened with clamps and are located outside the ceilings and are freely accessible.

Due to the limitation on the number of permissible turns, the number of possible chimney configurations is quite limited. There are three main options depending on the location of the exhaust vent. Two more can be obtained by mirroring the previous ones.

All requirements and recommendations stated above apply to devices with an open combustion chamber. The standards also allow the removal of combustion products through an external wall without a vertical smoke duct from geysers with a closed combustion chamber and forced release of exhaust gases. In this case, installation is carried out according to the manufacturer's instructions in compliance with the standard distances and lengths of the coaxial chimney specified in SP 42-101-2003.

Connectors for geyser air ducts

Calculation of hood parameters

Before starting work on installing a chimney for a geyser in an apartment or private house, it is necessary to calculate the parameters of the exhaust channel. These parameters determine the required amount of air removed from the room.

When calculating, the following indicators should be taken into account:

• power of heating devices;
• volume of exhaust gases;
• difference in temperatures of outside air and combustion products;
• the height of the chimney pipe (for gas installations at least 2 m).

There are many types of pipelines for geysers, of different diameters, shapes, and lengths. Standard chimney diameters are 110-130 mm. For dispenser power up to 19 kW, a pipe with a diameter of 11 cm is used, above – 13 cm.

Adapters for geysers

Chimney tee for geyser

Clamp for fastening the geyser pipe to the wall

Corrugated aluminum chimney

Exhaust pipes are installed on the gas water heater in an apartment or house, and are designed to exhaust burnt gas into the ventilation shaft. The air duct pipes for the geyser are made of steel and covered with a high-quality protective coating of white heat-resistant enamel.

Enameled white air ducts of a geyser are highly safe, aesthetically pleasing and resistant to the destructive effects of hot gas and the resulting carbonic acid. White enamel applied to the chimneys of a geyser easily withstands elevated temperatures and protects the outside of the pipe from corrosion. White air ducts "Whitesteel" have the following advantages:

• Special sealed Z-shaped seam
• Easily cut to size with a hacksaw or grinder
• Chemical resistant - resistant to condensate and carbonic acid
• Covered with white heat-resistant enamel to match the color of the geyser
• Recommended for installation by the gas service of St. Petersburg

• High strength steel 0.6mm, which reduces to zero the possibility of damaging the chimney of a geyser and ensures durability

• High quality workmanship. Bends and other elements are made as compact as possible to look aesthetically pleasing in your kitchen or bathroom and take up as little space as possible. Elements are decoratively thought out and measured according to air resistance indicators

VentDom is a manufacturer of chimneys for geysers "Whitesteel"® in St. Petersburg, carrying out retail and wholesale sales. In most apartments, modern enameled exhaust pipes are installed; they look beautiful and do not spoil the appearance of the room; they are much more reliable and safer than corrugated pipes. Modular chimney pipes for geysers are used to remove hot air from geysers.

White chimneys are recommended for installation on geysers of all manufacturers: Neva, Neva Lux, Electrolux, Bosch, Zanussi, Roda, Gorenje, Ariston, Termet, Baxi, EDISSON, Mora Top, Ladogaz, Elsotherm (tested for compatibility with each brand).

Structurally, chimneys are modular elements that are connected to each other in series, similar to a constructor. Due to the modular assembly principle, you can independently install the chimney of a gas water heater with your own hands while meeting the necessary safety requirements. During installation, the pipes are laid from the outlet of the column to the wall flange fixed to the opening of the common house ventilation shaft. Additional sealing of chimney seams is not required. To pass through or close to a suspended ceiling (film), a heat-insulating mineral wool cylinder is used, which is placed over the pipes.

Corrugated flexible chimneys are prohibited for installation on a gas water heater according to SNiP and are allowed for installation only on an exhaust hood. It is also prohibited to combine the hood from the stove and the gas water heater into one hole in the common shaft. According to the design, such houses have 2 separate shafts; the building manager or neighbors living on the same riser as you can help you find it. If the second shaft could not be found, the gas water heater is connected to the ventilation duct, and the hood starts in recirculation mode.

The nuances of adjusting draft in a gas water heater

The quality of combustion products removal depends directly on the traction force. According to the regulations, the required parameters for carbon monoxide removal are at least 1.5 m³/hour at a flow rate of about 20 m/sec.

Undoubtedly, the main factor in the formation of good draft is the height of the chimney. The elevation of the chimney above the adjacent roof area according to building standards is at least 0.5 m; with a flat roof this figure is 200 cm.

If the object is surrounded by taller buildings, or there are tall trees nearby, the nature of the wind support zone is monitored. Next, if necessary, increase the height of the smoke exhaust pipe.

Upon completion of installation work, the tightness of the chimney structure is checked, taking into account that this indicator also affects the quality of the traction force. It is prohibited to install umbrellas and deflectors on the chimney, which may contribute to the disappearance of draft as a result of freezing of the tip. Under operating conditions, the speakers in a room with closed doors are equipped with a ventilation opening under the entrance structure with an area of ​​0.2 m² or holes are made in the lower part of the canvas. To prevent automatic shutdown of the gas water heater due to insufficient air flow in a room with hermetically sealed windows, you should set the micro-ventilation mode for the sashes when the unit is operating.