The Caleffi ROBOCAL Automatic Float Air Vent with 15mm Compression Connection (MPN 502649) is the UK compression-fit version of Caleffi's Series 5026 Robocal automatic air vent — a compact float-type vent with vertical discharge, adapted for direct in-line installation in a 15mm pipework circuit without adapters. The polypropylene float, silicone rubber obturator, and stainless steel spring continuously remove dissolved and free air from heating and cooling circuits. Rated to 10 bar / 115°C with a maximum discharge pressure of 6 bar, it carries WRAS approval and is compatible with water/glycol solutions up to 30%.
WRAS Approved
The Caleffi Robocal Series 5026 holds WRAS (Water Regulations Advisory Scheme) approval — confirming compliance with UK Water Supply (Water Fittings) Regulations 1999 and suitability for use in UK heating and water systems.
Installation Orientation
The 502649 must be installed vertically upright with the discharge cap at the top. The float mechanism relies on gravity and will not operate correctly if tilted or inverted.
Outlet Cap Must Be Open
To allow venting (both automatic and manual), the outlet cap/plug must be rotated approximately one full turn anti-clockwise from fully closed. A fully tightened cap prevents all air discharge.
Key Features
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Continuous Automatic Venting
When air accumulates, the float falls, the obturator opens, and air is discharged through the vertical outlet. As water rises, the float lifts and reseals — fully automatic, no manual adjustment needed during operation.
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Dry Obturator Design
The float and internal layout are engineered so the silicone rubber obturator seal never contacts system water during normal operation — preventing debris and magnetite contamination of the sealing face, the primary cause of auto-vent failure.
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15mm Compression Fitting
The base incorporates a direct 15mm compression connection — install in-line in a 15mm pipe run at any high point. No reducing socket or threaded adapter needed.
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Anti-Vibration Float
The float carrier includes an anti-rotation and anti-vibration system, preventing pump turbulence from causing nuisance opening and reducing wear on the float mechanism over time.
Technical Specifications
| MPN |
502649 |
| Series |
5026 — ROBOCAL Automatic Air Vent |
| Connection |
15mm compression fitting |
| Discharge Direction |
Vertical (upward) |
| Body / Cover Material |
Brass EN 12165 CW617N |
| Float Material |
Polypropylene (PP) |
| Obturator Material |
Silicone rubber |
| Spring Material |
Stainless steel 1.4310 / AISI 302 |
| Seals |
EPDM |
| Medium |
Water; glycol solutions max 30% |
| Max Working Pressure |
10 bar |
| Max Discharge Pressure |
6 bar |
| Max Working Temperature |
115°C |
| Body Dimensions (approx.) |
Height 77mm; Body diameter Ø40mm |
| WRAS |
Approved |
| Manufacturer |
Caleffi S.p.A., Italy |
Frequently Asked Questions
Where is the best position to install the 502649 on a heating system?
Install at the highest points in the pipework circuit where air naturally collects: immediately above the boiler heat exchanger or heat pump, on buffer vessel headers, at manifold high points, and at any circuit apex. Multiple vents may be needed on complex circuits.
Does this model include a shut-off cock for easy removal?
No — the 502649 (Series 5026) is the standard version without an integral shut-off cock. To remove the vent body for inspection without draining, either fit a Caleffi Series 561 isolating valve below it, or choose the Series 5027 Robocal (with built-in automatic shut-off cock).
Can this be used on a heat pump or underfloor heating system?
Yes — the 115°C and 10 bar ratings give ample headroom for heat pump primary circuits (typically below 65°C) and UFH circuits. Confirm that the system fluid is water or a glycol/water mix not exceeding 30% glycol concentration.
Why does the vent have a dry obturator?
The dry obturator design keeps the silicone rubber sealing face away from system water during normal operation. This prevents magnetite sludge, limescale, and inhibitor residue from coating the seal — the leading cause of auto air vent failure in older designs.
What is the UPC / EAN for this product?
EAN / UPC: 8016615056228.
