Caleffi 551 DISCAL air separator

DISCAL 551 is a series of air separators that remove air from the water in closed heating and cooling circuits. It has 18 models: 17 air separators with technopolymer or brass body, plus a high-performance automatic air vent from the same series.

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Body: Technopolymer or brass
Max. working pressure: Technopolymer: 3 bar; brass: 10 bar
Max. discharge pressure: Brass models: 10 bar
Temperature range: Technopolymer: 0–90 °C (551805/806: max. 110 °C); brass: 0–110 °C

Models (18)

Code	Model	Body	Connection	Max. pressure	Temperature
551805	DISCAL air separator, hygroscopic cap	Technopolymer	3/4" female	3 bar	max. 110 °C
551806	DISCAL air separator, hygroscopic cap	Technopolymer	1" female	3 bar	max. 110 °C
551205	DISCAL air separator	Technopolymer	3/4" female	3 bar	0–90 °C
551206	DISCAL air separator	Technopolymer	1" female	3 bar	0–90 °C
551207	DISCAL air separator	Technopolymer	1 1/4" female	3 bar	0–90 °C
551202	DISCAL air separator	Technopolymer	Ø 22	3 bar	0–90 °C
551203	DISCAL air separator	Technopolymer	Ø 28	3 bar	0–90 °C
551208	DISCAL air separator	Technopolymer	1 1/2"	3 bar	0–90 °C
551209	DISCAL air separator	Technopolymer	2"	3 bar	0–90 °C
551705	DISCAL air separator	Brass	3/4" female	10 bar	0–110 °C
551706	DISCAL air separator	Brass	1" female	10 bar	0–110 °C
551716	DISCAL air separator	Brass	1" male	10 bar	0–110 °C
551005	DISCAL air separator with drain	Brass	3/4" female	10 bar	0–110 °C
551006	DISCAL air separator with drain	Brass	1" female	10 bar	0–110 °C
551007	DISCAL air separator with drain	Brass	1 1/4" female	10 bar	0–110 °C
551008	DISCAL air separator with drain	Brass	1 1/2" female	10 bar	0–110 °C
551009	DISCAL air separator with drain	Brass	2" female	10 bar	0–110 °C
551004	DISCAL high-performance automatic air vent	Brass	1/2" female	10 bar	0–110 °C

Series specifications

Body	Technopolymer or brass
Max. working pressure	Technopolymer: 3 bar; brass: 10 bar
Max. discharge pressure	Brass models: 10 bar
Temperature range	Technopolymer: 0–90 °C (551805/806: max. 110 °C); brass: 0–110 °C
Connections	3/4"–2" threaded, 551716 male, Ø 22 and Ø 28
Installation	Adjustable for horizontal and vertical pipes
Technical brochure	01337 (technopolymer), 01060 (brass), 01124 (air vent)

Accessories

Code	Product	Use
CBN551202	Insulation for technopolymer DISCAL	For 551202, 551203, 551205, 551206
CBN551207	Insulation for technopolymer DISCAL	For 551207
CBN551208	Insulation for technopolymer DISCAL	For 551208
CBN551209	Insulation for technopolymer DISCAL	For 551209

How to choose

Pressure: if system pressure exceeds or may exceed 3 bar, choose a brass model (551705/706/716 or 551005–551009); technopolymer models are for max. 3 bar.
Temperature: the new technopolymer range is limited to 0–90 °C; for hotter circuits the brass models work up to 110 °C.
Copper pipe: 551202 (Ø 22) and 551203 (Ø 28) connect directly to copper lines.
Drain: if you want to empty water and dirt collected at the bottom, choose the brass 551005–551009 range with drain.
On chilled water lines: add the CBN insulation shells to the technopolymer models.

How to write it in a quote

Always state body material and pressure limit, because the same size exists in 3 bar and 10 bar versions: "Caleffi 551006 DISCAL air separator 1", brass body, with drain, 10 bar, 0–110 °C". If an insulation shell is used, add the CBN code as a separate line.

FAQ

What is the difference between an air separator and an automatic air vent?

An automatic air vent only discharges air that collects at its location. An air separator removes air from the circulating water as it flows through and discharges it via its vent.

How do technopolymer and brass DISCAL differ?

Technopolymer models are for a max. working pressure of 3 bar; brass models are rated for 10 bar working and 10 bar discharge pressure and 0–110 °C. Use technopolymer in low-pressure residential circuits and brass in higher-pressure systems.

Can it be fitted on a vertical pipe?

Yes. The air separators in the series can be adjusted for horizontal or vertical pipes.

Which models do the insulation shells fit?

CBN551202 fits 551202, 551203, 551205 and 551206; CBN551207, CBN551208 and CBN551209 fit the models with the same number. The shells are for the technopolymer models.