Ducting for a gas water heater

Solving the issue with the removal of exhaust gases from such a flow heater as a gas heater, it is necessary to choose the right ductwork for this equipment and know the nuances of its installation. The main purpose of the duct is to exhaust combustion products from the speaker to the street - through a hole in the wall or through the chimney shaft.

Air ducts for gas boilers are classified according to several characteristics:

• According to the material of manufacture, the ducting comes in steel or aluminum. Made of aluminum foil corrugated duct is a cheap and affordable option, but it is not recommended for frequent use of the speaker, as it quickly burns through.
• Depending on where the combustion products go, the ducting can be chimney (it connects to the ventilation well) or coaxial (it goes out through the wall of the house).

For the manufacture of such steel ducts, high quality steel is used. Often it is specially coated with white enamel with heat-resistant properties. They have a smooth surface, which has a positive effect on aerodynamic drag. Such ducts are less fouled and make minimal noise when the speaker is in operation.

Quite often steel ducts are galvanized pipes. They have a low weight, high reliability and minimal noise during use of the equipment. The disadvantage of such pipes is the risk of icing in the winter, so in the case of installation of such a duct outside the building should take care of insulation of the pipe.

A steel pipe that has had a protective enamel coating applied on top is more protected from external influences. First of all, the enamel prevents the formation of rust on the surface of the duct. In addition, such enameled pipe is characterized by high temperature resistance (it can easily withstand temperature changes), resistance to chemical attack of acids or alkalis, as well as considerable mechanical strength. In addition, the different colors of the enamel makes such an air duct attractive in appearance.

The most optimal shape for the air duct of a gas-fired boiler is round. It is with this form the efficiency of the removal of combustion products will be the best. If the shape of the duct is square, this will affect the efficiency of the hood.

The duct should not have an excessive length, because the bends of the ventilation pipe reduce the performance. At the same bends more than 90 degrees have a negative effect on the draft. The optimum length of the duct is considered up to three meters.

It is important to make sure that the diameter of the duct is not less than the diameter of the speaker outlet. Standard parameters are called 11 and 13 cm. To determine which diameter is necessary in a particular case, take into account the power of the equipment and the number of water outlets. If the speaker works with a capacity of up to 20 kW and the water comes to one point, you need a pipe with a diameter of 110 mm. With a higher power and the need to serve several points requires a duct with a diameter of 130 mm.

Installation work will depend on the selected duct.

• If you settled on a steel pipe, you need to buy the necessary adapters to it. To know what length of pipe will be needed, measure the distance from the speaker to the hole in the ventilation duct. Installation of the pipe and adapters is easy enough and resembles the assembly of a construction set. You should use sealant to fix the duct and treat its connections.
• If you decide to use corrugated ducting, you do not need to buy any adapters. Corrugated duct is stretched to the required length to connect the ventilation system and the speaker. If you want to add length, for this use metal adhesive tape.

In order for the gas boiler to work effectively, it is necessary to correctly calculate the height of the chimney. How to do this properly can be seen in the following video.