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Vacuum solar collector Altek SC-HD-30 DRAINBACK

49,196 ₴

Other

Sunday 11:55

Україна

Київ Get directions →

вул. Стеценка, 14/44

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Published 4 days ago by Solar-Tech

49,196 ₴

In Other category

вул. Стеценка, 14/44, Київ, Україна

Get directions →

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Drainback heliosystem protection technology

The drainback technology is designed to protect the heliosystem from boiling or freezing of the heat transfer fluid and from formation of airlocks. Overheating and presence of air in the system are the main causes of failures that can lead to serious damage. The system consists of special solar collectors, a special tank for draining the heat transfer fluid, a pump group and a storage water heater with a built-in heat exchanger.

Principle of operation of the drainback system

Before operation the solar collectors are filled with air, and all the heat transfer fluid is below their level in the pipelines, the heat exchanger and the special reservoir (drainback tank).

When the temperature in the solar collector rises to the set value, the pump switches on, the heat transfer fluid fills the collectors (displacing the air), absorbs heat and flows to the heat exchanger where it gives off heat to the water. When operation ends, the pump switches off and the heat transfer fluid drains from the collectors, which are again filled with air.

The main advantage of such a system is the ability to protect propylene glycol-based heat transfer fluid from exposure to high temperatures (which reach 200 ˚C and above). Because of this protection principle the DRAINBACK SYSTEM can be called "self-draining." Mainly, this technology is used for small heliosystems with one circulation circuit and one group of solar collectors.

Requirements for the system:

The need to use more powerful circulation pumps than usual;

The need for periodic complete replacement of glycol-based heat transfer fluid, since the constant presence of air in the system leads to oxidation of the liquid with formation of solid deposits;

The heliosystem must not have check valves, an air vent or expansion tanks;

Connecting multiple collectors in rows is possible only in parallel using a "Tichtelmann loop"

The amount of heat transfer fluid in the system must take into account that a sufficient amount of heat transfer fluid must always remain in the drainback tank.

Features:

Connection nozzles are located on the rear panel of the housing to allow draining of the heat transfer fluid.

Can be installed on flat and pitched roofs.

If a standard pump with a head of 6-7 m.w.c. is used in the system, the height difference between the highest and lowest points of the system should not exceed 6 m.

Ideal system option for temporary-use facilities (dachas, country houses);

The initial investment amount is lower due to a smaller number of system components;

Possible use of water as the heat transfer fluid;

During prolonged absence of heat draw-off the heat transfer fluid does not overheat;

Back-cooling of the boiler through natural circulation is excluded.

Specifications of the vacuum collector Altek SC-HD-20:

Tube type

Heat pipe (AlN/AlN-SS/Cu)

Number of tubes

Collector area, (m2)

4.51

Vacuum tube size, (mm)

58х1800

Condenser diameter, (mm)

Condenser length, (mm)

Absorber area, (m2)

2.42

Aperture area, m²

1.88

Recommended tank capacity (l)

275 - 325

Maximum heating temperature, (°C)

250

Rated operating temperature, (°C)

-20+90

Maximum operating temperature, (°C)

100

Efficiency, n

0.744

Frame and collector

aluminum alloy

Heat exchanger material

copper

Insulation material

mineral wool 37 mm

Thermistor sleeve, mm

ф8*100

Maximum working pressure, (MPa)

0.6

Recommended flow, l/min* m2

Vacuum tube holders

Latch with additional fixation

Installation type

Flat, pitched, vertical surfaces (inclination angle 15-60º)

Metal thickness

Dimensions HxWxD, (mm)

Weight, (kg)

Service life

not less than 15 years

Published on 2026/10/11

Description