Where should the AVC32 air vent be installed in a steam system?

Install the AVC32 at the highest point of the steam main or equipment where air accumulates. The capsule must be positioned horizontally with the cover at the top. Pipe the outlet to a safe discharge location and fit isolation valves upstream and downstream for maintenance access.

Can the AVC32 be insulated after installation?

No. The air vent must not be insulated. The thermostatic element relies on sensing the temperature difference between air and steam. Insulation would interfere with proper operation and may cause steam loss.

What spare parts are available for field maintenance?

Spirax Sarco offers a capsule and seat assembly set (includes parts 2, 3, 17, 18), strainer screens (packet of 3), and cover gaskets (packet of 3). The capsule assembly can be replaced without removing the body from the pipeline.

What is the difference between pressure limits for different flange standards?

Operating limits vary by connection type: Screwed, socket weld, butt weld, and ANSI 300 flanged versions are rated for the full pressure-temperature envelope. EN 1092 PN40 and JIS/KS 20K flanges have slightly reduced limits, while ANSI 150 and JIS/KS 10K flanges have lower maximum ratings. Refer to the pressure-temperature chart for exact limits.

Is material certification available for critical applications?

Yes. The AVC32 is available with EN 10204 3.1 certification. All certification and inspection requirements must be specified at the time of order placement.

SPIRAX SARCO · STEAM SYSTEM ACCESSORIES

Spirax Sarco AVC32 Carbon Steel Thermostatic Air Vent for Steam Systems

Name: Spirax Sarco AVC32 Carbon Steel Thermostatic Air Vent for Steam Systems
Brand: Spirax Sarco

Spirax Sarco AVC32 carbon steel air vent for steam systems. Balanced pressure thermostatic design, PN40 rated. Contact PC Engineering for pricing.

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Overview

The Spirax Sarco AVC32 is a carbon steel balanced pressure thermostatic air vent designed for efficient air removal from steam systems. Air accumulation in steam mains and process equipment reduces heat transfer efficiency and can cause corrosion — the AVC32 addresses this by automatically venting air while preventing steam loss.

This maintainable air vent features an integral flat strainer screen and straight connections for simplified installation. The balanced pressure thermostatic element responds to temperature differentials, opening to discharge air and non-condensable gases while closing tightly when steam reaches the sensing element.

All pressure-bearing components are manufactured by TÜV-approved suppliers in accordance with AD-Merkblatt WO/TRD100, ensuring consistent quality for demanding industrial applications. The AVC32 fully complies with the European Pressure Equipment Directive 97/23/EC and is available with EN 10204 3.1 material certification when specified at order placement.

Key Features

Balanced pressure thermostatic operation for reliable air venting
Carbon steel construction suitable for high-pressure steam systems
Integral flat strainer screen prevents debris ingress
Maintainable design — capsule assembly can be serviced in-line
Multiple connection options: screwed BSP/NPT, socket weld, butt weld, flanged
Wide flange compatibility: EN 1092 PN40, ANSI 150/300, JIS/KS 10K/20K
TÜV-approved pressure-bearing components
PED 97/23/EC compliant

Specifications

Parameter	Value
Sizes Available	DN15 (½"), DN20 (¾"), DN25 (1")
Maximum Allowable Pressure (PMA)	50 bar g @ 50°C
Maximum Allowable Temperature (TMA)	400°C @ 35 bar g
Maximum Operating Pressure (PMO)	32 bar g (saturated steam)
Maximum Operating Temperature (TMO)	287°C @ 32 bar g
Minimum Operating Temperature	0°C
Minimum Allowable Temperature	-60°C
Body Design Rating	PN40
Cold Hydraulic Test Pressure	75 bar g
Kv Value (all sizes)	0.8
Body/Cover Material	Carbon Steel DIN 17243 C22.8 / ASTM A105N
Capsule Material	Stainless Steel
Valve Seat Material	Stainless Steel BS 970 431 S29
Strainer Screen Material	Stainless Steel AISI 304
Cover Gasket	Stainless steel reinforced exfoliated graphite
Connection Types	Screwed BSP/NPT, Socket Weld (BS 3799), Butt Weld (EN 12627), Flanged
Flange Standards	EN 1092 PN40, ANSI B16.5 Class 150/300, JIS/KS 10K/20K
Size	A (mm)	A1 (mm)	B (mm)	C (mm)	D (mm)	E (mm)	Weight Screwed/SW/BW (kg)	Weight Flanged (kg)
DN15 (½")	95	150	94	64	17	37	1.4	2.9
DN20 (¾")	95	150	94	64	19	37	1.4	—
DN25 (1")	95	160	94	64	23	37	1.5	—

Applications

The AVC32 air vent is suited for steam distribution systems across various industrial sectors:

- Power generation — steam mains, turbine auxiliaries - Refineries and petrochemical plants — process steam headers - Pharmaceutical manufacturing — sterilization and heating systems - Food and beverage processing — steam-heated process equipment - Textile mills — dyeing and finishing steam systems - Paper and pulp plants — drying sections and steam distribution - General manufacturing — any steam system where air accumulation affects process efficiency

Install at the highest point of steam mains or equipment where air naturally collects. The unit must be mounted with the capsule horizontal and the cover facing upward. Do not insulate the air vent body.

Frequently Asked Questions

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Contact PC Engineering for pricing, availability, and technical support for the Spirax Sarco AVC32 Carbon Steel Air Vent. Call us or fill in our inquiry form — our engineers will respond within 24 hours.

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