How to drain the boiler

Most heating systems operate by transferring thermal energy through a coolant. Maintenance of the entire heating complex, as well as individual elements, requires draining the liquid. The need to repair or replace the boiler is impossible without releasing the internal cavity from the water.

Training

To drain the liquid from the gas heating equipment, it is necessary to prepare a hose, the inner diameter of which must correspond to the outer size of the drain fitting tap located below the boiler level. Such a valve is installed on the "return" of heating, at the lowest point. In addition to the hose, a container is prepared that has the same volume as the estimated amount of water to be drained.

The preparatory work also includes checking the shut-off valves of the attached equipment, including cranes, on the "feed" and "return" of the boiler.

IMPORTANT! Checking the valves is carried out only with the heating unit switched off! Overlapping the valve on the main pipeline in operating mode will result in equipment breakdown!

After checking, the hose is connected to the drain fitting, sent to the tank and the unit is turned off.

Types of boilers

For heating of premises using various types of equipment. By the type of fuel on which they operate they are divided into:

• solid fuel;
• electric;
• liquid fuel equipment;
• gas;
• combined units.

The specificity of solid fuels allows us to divide the equipment into several subspecies.

REFERENCE! Combined units are manufactured using two sources of heating, often combine electric with another type.

By appointment:

• single-circuit, only for heating systems;
• double-circuit, for heating and preparation of hot water.

Most designs of heating equipment have internal cavities in which the coolant is heated to the set temperature. When draining water from the boiler, the inner part is freed from the liquid and makes it possible to service all components and connections of the unit.

Ways to drain water

After completing the preparatory work, open all the radiator taps, then unscrew the valves regulating the flow of coolant (if any). After this, the drain bypass is opened and the liquid is directed into a specially prepared container. First, the pressure on the manometer will drop, and then, accompanied by a quiet hiss, the jet will fill the container.

A sound similar to a low-pitched whistle will be emitted by an automatic air vent, which complete the heating system. The presence of sound indicates the serviceability of the device, which vents excess air during operation of the unit. The considered method released from the water not only the boiler, but also all the heating appliances and pipes. For better emptying of devices, they use Maevsky cranes, opening each of them in turn.

ATTENTION! When the heat exchanger of the hot water heating of the double-circuit boiler is empty, after shutdown, first open the hot water tap until the liquid cools down. Then shut off the cold water supply and, if necessary, release the heat exchanger from the contents, unscrew the fitting of hot water supply.

Modern boilers, especially gas ones, are equipped with an automatic air blower and a drain fitting. To drain the liquid from such a unit, it is enough to open the drain valve, after carrying out preparatory work. If the equipment is installed at the top of the heating system, liquid will spill out, freeing only the boiler cavity. And through the unit installed below the radiators, water flows from the upper appliances.

IMPORTANT! In order not to drain the liquid from all circuits of the heating system, shut-off valves of the boiler are used, which connect the equipment to the "feed" and "return" pipes.

In what situations is the water drained?

Carrying out work on draining the liquid from the boiler is carried out:

• when replacing heating equipment;
• upon detection of a malfunction of the unit and repair of individual components;
• if necessary, eliminate leaks at the connections of taps, fittings or other nozzles of the unit;
• when the heating is off, in the winter, for a long period;
• when replacing the coolant.

Repair and maintenance of the heating system requires draining the fluid. Evacuation of equipment from the coolant can be performed by everyone with small technical skills. The ability to drain water from the boiler will allow you to easily cope with any equipment malfunction, which is especially important in the winter.