Brass Compression Fittings Reducing-Equal T Piece Female Coupling Connector

Choose an equal T piece when all three ports connect to pipe of the same outer diameter — for example, branching a 22 mm cold-water main into two 22 mm feeds. Choose a reducing T piece when the branch port needs to be a smaller diameter than the run — for example, a 28 mm main run with a 15 mm branch to a smaller appliance. Check the Size option carefully: the format is Run × Centre × Run, so "28mm × 15mm × 28mm" means a 28 mm run with a 15 mm branch.

These brass compression fittings are designed primarily for copper pipe and brass pipe. They are also compatible with certain rigid plastic pipes (such as chrome-plated brass or rigid CPVC) provided the pipe outer diameter matches the fitting size exactly. They are not suitable for soft polyethylene (PE) or flexible push-fit pipe without an insert support sleeve. If in doubt, contact us to confirm compatibility before ordering.

No specialist tools are required. You will need two adjustable spanners (or open-ended spanners sized to the fitting nut): one to hold the fitting body and one to tighten the compression nut. Do not over-tighten — typically one full turn past hand-tight is sufficient to compress the olive and create a leak-free seal. Avoid using PTFE tape on compression joints; the seal is made by the olive, not the thread.

Brass has inherent corrosion resistance to water, moisture, and many common chemicals, making it suitable for indoor plumbing, underfloor heating, and sheltered outdoor installations. For fully exposed outdoor environments or aggressive water chemistry (very soft or acidic water), consider applying a protective coating or consult a plumbing engineer. These fittings are not recommended for direct burial without additional protection.

Compression fittings can generally be disconnected and reassembled, but the olive (the soft metal ring that creates the seal) deforms permanently when first compressed. If you disconnect the fitting, the existing olive may not re-seal reliably. It is best practice to replace the olive with a new one when reconnecting. Replacement olives are available separately in matching sizes.

In metric plumbing systems, the most common sizes are 15 mm (basin taps, radiator valves), 22 mm (main cold and hot water distribution), and 28 mm (boiler primary circuits and larger distribution runs). For BSP-threaded connections, select the variant that shows a fractional dimension in the centre port (e.g. "22mm × 1/2" × 22mm") to match standard BSP male fittings. If you are unsure, measure the outer diameter of your existing pipe with calipers before selecting a size.

Brass is widely used in potable water applications. However, regulatory requirements for drinking water fittings vary by region. If your installation requires compliance with a specific standard (such as WRAS approval in the UK or NSF/ANSI 61 in the US), please contact us to confirm certification status before purchasing.