Spirax Sarco AVC32 Carbon Steel Air Vent

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Spirax Sarco AVC32 Carbon Steel Air Vent

AVC32 is a Spirax Sarco carbon steel balanced-pressure thermostatic air vent for steam systems, fitted with an integral flat strainer screen. Pressure-bearing components are made by TÜV-approved suppliers to AD-Merkblatt WO/TRD100, making it suitable for higher-pressure steam mains and equipment high points where air and other non-condensable gases need to be removed.

Product specification
Maintainable balanced-pressure thermostatic air ventCarbon steel body with integral flat strainer screen and straight connectionsSaturated steam operating pressure up to 32 bar g at temperatures up to 287 °CAvailable in 1/2", 3/4" and 1" with threaded, socket weld, butt weld and flanged connections

Quick facts

Model AVC32
Type Balanced-pressure thermostatic air vent
Body material Carbon steel
Size range 1/2", 3/4", 1" (DN15 to DN25)
Maximum operating pressure (saturated steam) 32 bar g
Maximum operating temperature 287 °C @ 32 bar g

Where AVC32 fits in the air vent range

AVC32 is a model-level route inside the wider air vents and air eliminators range. It suits steam-system users who have already moved from a category search to model selection, particularly for higher-pressure mains or installations that call for welded or flanged connections.

Within the same air vent range, AVC32 and the brass AV13 form a high/low pairing by material and pressure class. AV13 is oriented toward lower-pressure threaded applications, while AVC32 offers a carbon steel body, higher operating pressure and socket weld, butt weld or flanged connections for steam mains.

Product facts

Available technical material (TI-P123-15) confirms the following:

  • AVC32 is a maintainable carbon steel balanced-pressure thermostatic air vent for steam systems
  • It includes an integral flat strainer screen and straight connections for direct in-line installation
  • The body, flanges and cover are carbon steel; the capsule, valve seat, strainer screen and spring are stainless steel
  • Pressure-bearing components are made by TÜV-approved suppliers to AD-Merkblatt WO/TRD100
  • It complies fully with the Pressure Equipment Directive 2014/68/EU, with EN 10204 3.1 certification available
  • The cold Kv value is 0.8 for all sizes

Technical data summary

ItemValue
Body materialCarbon steel (DIN 17243 C22.8 / ASTM A105N)
Internal materialsStainless steel (capsule, valve seat, strainer screen, spring)
Sizes1/2”, 3/4”, 1” (DN15, DN20, DN25)
Maximum allowable pressure PMA50 bar g @ 50 °C
Maximum allowable temperature TMA400 °C @ 35 bar g
Minimum allowable temperature-60 °C
Maximum operating pressure PMO (saturated steam)32 bar g
Maximum operating temperature TMO287 °C @ 32 bar g
Minimum operating temperature0 °C
Cold hydraulic test pressure75 bar g

AVC32 is also safe to use under full vacuum conditions.

Connection formats and available specifications

The connection formats covered by the technical material include:

  • Screwed BSP T Rp (ISO 7-1) or NPT
  • Socket weld ends to BS 3799
  • Butt weld ends to EN 12627
  • Flanged to EN 1092 PN40, ANSI B16.5 Class 150 and 300, and JIS/KS 10K and 20K

The complete-unit specifications currently selectable at the top of this page focus on 1/2", 3/4" and 1" threaded BSP connections. Confirm welded or flanged requirements against site conditions before ordering.

Installation and selection checks

AVC32 should be installed at the highest point of a steam main or item of equipment, where air collects most readily, with the capsule horizontal and the cover at the top. The discharge should be piped to a safe place, and the air vent itself must not be insulated. Fit isolation valves upstream and downstream to allow future maintenance.

Before specifying AVC32, confirm:

  • Whether the site connection is threaded, socket weld, butt weld or flanged, and the relevant connection standard
  • Whether a 1/2", 3/4" or 1" size is required
  • That the operating pressure is within the 32 bar g saturated steam range
  • That the installation point is a genuine air-collection high point and the capsule can be mounted horizontally
  • That isolation valves are provided upstream and downstream for in-line maintenance
  • That the discharge can be safely routed away from personnel and equipment

Technical documentation coverage

TI-P123-15 covers the material construction, pressure and temperature limits, sizes and connection formats, Kv value, dimensions and spare parts for AVC32. Installation, maintenance and tightening torque detail is provided in the accompanying installation and maintenance guide (IM-P123-14).

Which steam-system applications AVC32 suits

Where the site problem centres on slow warm-up of higher-pressure steam mains, reduced heat transfer, gas accumulation in the steam space, or equipment high points that need continuous removal of non-condensable gases, and the connection format calls for welding or flanges, a carbon steel thermostatic air vent like AVC32 is generally a closer fit than a brass threaded model.

For lower-pressure systems based mainly on threaded connections, you can return to air vents and air eliminators to compare AV13 and other routes.

Technical Documentation

Document Reference Language Download
AVC32 Carbon Steel Air Vent for Steam Systems TI-P123-15 English Download

Installation and Maintenance

Document Reference Language Download
AVC32 Carbon Steel Air Vent for Steam Systems IM-P123-14 English Download

Continue your AVC32 selection route

AVC32 selection is normally focused on higher-pressure steam venting or applications that need welded or flanged connections, with operating pressure, connection format and installation position checked before ordering.

Talk to our international steam solutions team

If you need more information about product selection, technical documentation or steam system solutions, contact the Spirax Sarco team.