Compression 15mm x 8mm 1 Piece Reducer

The Compression 15mm x 8mm One-Piece Reducer from Evolve is a clever little fitting designed to simplify transitions between different pipe sizes—specifically from 15mm to 8mm. It's particularly useful in central heating systems or older pipework setups where smaller diameter pipes are still in use. This reducer works by fitting inside a standard 15mm compression fitting—such as a radiator valve, elbow, tee, or coupler—replacing the standard olive. Once in place, it allows the fitting to securely accommodate an 8mm pipe, providing a neat and compact solution without the need for bulky adapters or additional fittings. It’s ideal for both professional installers and DIY users who need a quick, reliable method for adapting pipework during upgrades, repairs, or modifications. The one-piece design means fewer parts to worry about, reducing the chances of leaks and simplifying installation.

Frequently Asked Questions

What does this reducer actually do?

It allows a 15mm compression fitting to securely connect to an 8mm pipe by replacing the olive. It’s a space-saving and convenient way to adapt between pipe sizes without needing extra joints.

Is it suitable for central heating systems?

Yes, it’s commonly used in central heating installations—especially in homes where 8mm microbore pipes are used for radiators and 15mm is used for the main supply lines.

Do I need any special tools to fit this reducer?

No special tools are needed. Just standard spanners or adjustable wrenches to tighten the compression fitting. Make sure the pipe is cut cleanly and inserted fully for the best seal.

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Every order is personally reviewed by our experienced team to ensure everything is correct before dispatch. We offer delivery from as little as the next working day on selected products, so please refer to the dark blue Estimated Delivery box above for the expected delivery timeframe for this item.

We work with trusted manufacturers and specialist delivery partners to ensure your order arrives safely and on time. You'll receive tracking details once your order has been dispatched, and if we need to confirm any delivery details, one of our team will contact you directly to keep everything running smoothly.

Roof Tiles & Fittings:

We recommend ordering an additional 10% of roof tiles to allow for any breakages that may occur during delivery or handling. Roof tiles are naturally fragile, and having a few extra on site helps prevent delays and ensures your roofing project can be completed without interruption.

Multiple Products from the Same Supplier

If you're ordering multiple products from the same supplier, your order will be dispatched together once all items are ready. This means the longest lead time will apply.

If you need part of your order sooner, please call us on 01202 113233. We can arrange a split delivery, although an additional shipping charge will apply.