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Black rubber O-ring for 13mm hard tube fitting

Alphacool

Alphacool O-Ring 11 x 3mm for HT 13mm fitting Black

SKU CH-SECY-V4ASJ

Replacement O-ring sized 11 x 3 mm for 13 mm hard-tube compression fittings

  • TypeFittings
  • Seals 13mm hard-tube connections reliably
  • Replaces worn O-rings in compression fittings
  • Black finish matches HT 13mm fitting aesthetics
  • Exact 11 x 3mm dimensions ensure proper fit
  • Single replacement ring restores leak-free loop

Replacement Seal for 13mm Hard Tube Fittings

This black O-ring is designed specifically for Alphacool 13mm hard tube compression fittings. It provides the essential seal between the fitting body and the tubing. The component is sold individually as a spare part for existing loops. It suits builders maintaining or modifying a custom liquid cooling system.

Thermals Noise and Power Draw

As a passive sealing component, this O-ring generates no heat and produces no audible noise. It does not draw any electrical power during operation. Its sole function is to maintain a leak-free connection under standard system pressure. Correct installation ensures reliable thermal performance of the loop.

Upgrade Context and Compatibility

This part replaces a worn, damaged or lost O-ring on a 13mm hard tube fitting. It is not a fitting itself and cannot adapt other tubing sizes or thread standards. The upgrade is worthwhile only when the original seal degrades or during routine maintenance. Buyers needing fittings for different tubing diameters must look elsewhere.

Highlights

  • Seals 13mm hard-tube connections reliably
  • Replaces worn O-rings in compression fittings
  • Black finish matches HT 13mm fitting aesthetics
  • Exact 11 x 3mm dimensions ensure proper fit
  • Single replacement ring restores leak-free loop

Specifications

TypeFittings

Questions about this item

How do I install this O-ring on a G1/4" HT 13mm compression fitting without damaging the seal?

Remove the old O-ring from the fitting groove, lubricate the new 11 x 3mm ring with coolant or distilled water, then press it evenly into the channel before tightening the compression nut onto the 13mm hard tube.

When should I replace the O-ring in my 13mm hard-tube loop?

Replace the 11 x 3mm seal whenever you disassemble the fitting, see visible cracks or flattening, or during annual loop maintenance to prevent slow leaks at the G1/4" joint.

What is the first sign that the O-ring is failing under continuous pressure and temperature cycling?

A slow seep of coolant at the compression fitting interface indicates the 11 x 3mm ring has lost elasticity and can no longer maintain a reliable seal on the 13mm hard tube.

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