Radiator 21K 300 x 500 output 373W

Product detailed description

Steel radiator with side connection for central heating in family houses.

• Connections: 4 x 1/2“
• Test pressure: 1.3 MPa
• Operating pressure: 1.0 MPa
• Heating medium temperature: hot water up to 110 °C
• Product: Stelrad Compact Softline
• Type: 11/20/21/22/33
• Overall height: 300 – 900 mm
• Overall length: 400 – 3000 mm
• Overall depth: 61/77/100/158 mm

Compact Softline low-temperature heating radiator is made of fine cold-rolled sheet steel to EN442-1 quality, with side panels and a top grille as a compact unit with a vertical water channel spacing of 33.3 mm. The convector sheet is welded to the internal channels. Before painting, all radiators go through a multi-stage cleaning process, including iron phosphating and a demineralised rinse. A primer coat is then applied, followed by a powder coat finish in Stelrad white 9016. Each radiator is packed in cardboard with sturdy corner protectors and in protective film. All units have mounting brackets on the back. Quality is verified in line with EN ISO 9001. Thermal output is verified in line with EN 442. The design complies with BAGUV safety guidelines.

Frequently Asked Questions

• What is the output of this specific radiator (300 x 500 mm, type 21K)? This size and type version has a declared thermal output of 373 W (according to EN 442, at the standard temperature drop) - when choosing the correct radiator size, base your choice on the calculated heat loss of the given room.
• What does the type designation 21K mean? The number before "K" (e.g. 11, 20, 21, 22, 33) indicates the radiator's construction type - the number of radiator panels/plates and convector fins in its structure; a higher number means more layers and therefore higher output at the same external dimensions. A radiator without the letter "V" in the type has a side connection - the classic placement of connections on the sides of the radiator, suitable for standard side pipe routing.
• What is the maximum operating pressure and temperature? The radiator is designed for an operating pressure of up to 1.0 MPa and a heating water temperature of up to 110 °C, with a test pressure of 1.3 MPa - typical domestic heating systems operate well below these values.
• What is the warranty on the radiator? The manufacturer provides a 10-year warranty on tightness and thermal output from the date of manufacture, provided professional installation, correct maintenance and operation are observed - the warranty does not cover mechanical damage caused during transport, handling or improper installation.
• Must the installation be carried out by a professional? Yes, connecting the radiator to the heating system (single-pipe or two-pipe, with forced circulation) should be carried out by a heating engineer/plumber, who will also ensure correct bleeding and balancing of the circuit.