Reliable and quick
New design
Flexvent
Automatic air vent
Owner’s Manual
Features and benefits:
- Easy to install
- Reliable and fast
- Captive cap with open/close function and leak prevention
- Substantial gap between water and closing: reduced chance of contamination
- Extensive product range
Flexvent: Improved design
Under the name ‘Flexvent’, Flamco offers a comprehensive range of automatic floating air vents.
Flexvent air vents have proven themselves in the market for decades. Flamco has improved the Flexvent automatic floating air vent even further in terms of both the design and execution.
The Flexvent floating air vent consists of a closed brass housing and an interior made entirely of plastic.
The water level lifts the float and keeps the air valve mechanism closed. When air collects in the vent housing, the water level drops, lowering the float and opening the vent valve.
The collected air is vented, allowing the water level to rise and the air valve to close again.
This process will keep repeating as long as air enters the Vent housing during normal operation.
Advantages and features
Extensive product range
Connection | Valve sleeve | Bubble breaker | Colour | Part No. |
R 1/8″ | no | yes | brass | 27775 |
R 3/8″ | yes | no | brass | 27750 |
R 1/8″ / R 3/8″ | yes | no | brass | 27780 |
R 1/2″ | yes | no | brass | 27740 |
G 1/2″ | no | yes | white | 27743 |
R 1/2″ | yes | no | nickel-plated | 27742 |
R 3/4″ | yes | no | brass | 27735 |
Other models
Flexvent H
With a ½” side connection allowing direct installation in one of the radiator plugs.
As this model is usually installed in plain sight, there are two models: nickel-plated and white.
Connection | Valve sleeve | Colour | Part No. |
R 1/2″ | no | Nickel-plated | 27710 |
R 1/2″ | no | white | 27711 |
Flexvent Super
The conical cap maximises the distance between the water level and vent valve.
The vent valve is integrated in the cap, so the float mechanism cannot be damaged from the outside.
Connection | Valve sleeve | Colour | Part No. |
G 1/2″ F | no | brass | 28520 |
Flexvent Max
Similar in appearance to the Flexvent Super ½” but with a ¾” connection and suitable for pressures of up to 25 bar.
Connection | Valve sleeve | Colour | Part No. |
Rp 3/4″ | no | brass | 28550 |
Flexvent Solar
Manually operated air vent for solar installa-tions with or without glycol addition.
Suitable for a supply temperature of -10 to 200°C and a maximum operating pressure of 10 bar.
Connection | Valve sleeve | Colour | Part No. |
R 3/8″ | no | Nickel-plated | 27785 |
Flexvent Top Solar
This model includes a ball valve and is suitable for a supply temperature of -30 to 180°C and a maximum operating pressure of 10 bar.
Connection | Valve sleeve | Colour | Part No. |
G 3/8″ M | no | brass | 28505 |
Flexvent Top
This automatic floating air vent works on the same principle but has a larger venting capacity.
Connection | Valve sleeve | Colour | Part No. |
Rp 1/2″ | no | brass | 28519 |
Flexvent Pro
The Flexvent Pro contains a filter that breaks down large air bubbles into smaller ones.
They can then find their way out more easily.
Connection | Valve sleeve | Colour | Part No. |
Rp 1/2″ | no | brass | 28519 |
Flexvent Top Aqua
This model is suitable for potable water installations with a water hardness of CaCO3 < 180 mg/l. Features ACS approval (KIWA approval on request).
Connection | Valve sleeve | Colour | Part No. |
Rp 1/2″ | no | brass | 28508 |
Even more Flamco products for heating and cooling
Flamco offers a wide range of products for heating, cooling and solar installations.From expansion vessels, safety valves, air and dirt separators to ball valves and handy installation aids such as the FlexConsole and T-plus.Our products are highly durable, energyefficient and have a long service life.
Flexcon Premium Expansion vessels | Airix Expansion vessels for potable water |
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Flexcon Solar Expansion vessels |
Flexcon PA AutoFill Pressure maintenance assistant |
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Prescor Safety valves (Heating) | Prescor Safety valves (Potable water) |
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Prescor Solar Safety valves | Prescor IC Fill Safety Group |
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Simplex KFE Ball Valves (Heating) | Simplex KFE Ball Valves (Potable water) |
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Simplex KFE Ball Valves (Solar) | XStream Air and Dirt separators |
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Flexvent
Reliable and quick
United Kingdom Aalberts hydronic flow control Washway Lane St Helens, Merseyside WA10 6PB T +44 1744 744 744 E uk.info@aalberts-hfc.com |
United Arab Emirates Aalberts hydronic flow control Silicon Oasis D206 HQ PO Box 341479 Dubai T +971 4 881 95 40 E ae.info@aalberts-hfc.com |
The Netherlands (Export) Aalberts hydronic flow control Fort Blauwkapel 1 1358 AD Almere T +31 (0)36 526 2300 E export.info@aalberts-hfc.com |
Documents / Resources
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Flamco Flexvent Automatic Air Vent [pdf] Owner's Manual Flexvent Automatic Air Vent, Flexvent, Automatic Air Vent, Air Vent, Vent |