Air removal from the heating system

Heating system air removal: automatic air vents, separators and vacuum degassers

In this category you will find professional heating system air removal equipment - from automatic valves to advanced microbubble and dirt separators and vacuum degassers. Efficient air removal is a critical element of the system, because air left in the liquid disrupts circulation, speeds up the wear of pump bearings and causes intense corrosion, which over time damages heat exchangers. Amegata supplies products from time-tested manufacturers such as Flamco, Spirotech, Reflex and Caleffi, ensuring long-lasting operation of B2B heating and HVAC systems.

Main types of air vents

• Automatic air vents (Flamco Flexvent, Caleffi Minical/Robocal) - installed at the highest points of the system, they remove accumulated air pockets.
• Microbubble separators (Spirotech Spirovent, Reflex Exvoid) - in-line devices that remove dissolved air directly from the flow using Spirotube or PALL ring technology.
• Combined dirt and air separators (Spirotech Spirocombi, Reflex Extwin) - combine microbubble removal and magnetic dirt separation in a single body.
• Vacuum degassers (Reflex Servitec) - essential in tall / high-pressure commercial buildings, where ordinary separators no longer release air because of the high static pressure.

How to choose air removal equipment for B2B projects

• System pressure (PN): Standard B2B sites require PN10 or PN16, high-rise buildings - PN25.
• Working temperature: Standard 110-120 °C, for solar collectors or industrial systems - 150 °C+.
• Connection diameter (DN) and flow velocity: For microbubble separators the flow velocity should not exceed 1.5 m/s (optimally < 1.0 m/s), otherwise the bubbles do not have time to separate.
• Installation location: Automatic air vents - at the highest points of the system (where air pockets accumulate). Microbubble separators - at the hottest point (on the supply line immediately after the boiler or heat pump), because that is where gas solubility in water is lowest.

Equipment maintenance and the most common faults

The most common problem is valve jamming caused by magnetite or corrosion products. Over a long service life the rubber (EPDM) seals and float mechanisms wear. Combined separators require a regular blowdown procedure - draining the accumulated dirt. We recommend using automatic air vents with non-return shut-off valves - this allows the head to be replaced without draining the heat transfer medium. Read why heat exchangers fail - the same causes apply to air vents.

FAQ about air removal

How does an air vent differ from a separator?
An automatic air vent removes the gas ("bubbles") from the air pocket at the top, at the highest points. A microbubble separator removes dissolved air directly from the flow using Spirotube or PALL ring technology.

Is a dirt separator with a magnet necessary?
Yes, especially if the system has modern pumps with ECM motors. Their magnets attract the system's magnetite (metal dust), so a magnetic dirt separator protects both the pumps and the heat exchangers.

When should an air vent be replaced?
Small automatic air vents (Flexvent, Caleffi Robocal) often have to be replaced every 3-5 years because of scaling or dirt. Flow separators (Spirovent, Exvoid), on the other hand, last 15+ years, because they have no small mechanisms that can jam.

Putting together an HVAC system for a commercial site? Contact the Amegata specialists - we will help you select the optimal Flamco, Spirotech, Reflex or Caleffi air removal solutions, including vacuum degassers for high-rise buildings.