Service Valves & Isolating Valves — 15mm, 22mm and Washing Machine Valves for UK Plumbers

Service valves and isolating valves are the unsung heroes of UK plumbing. Every time a plumber isolates a tap, swaps out a cistern valve, connects a washing machine or services a boiler, one of these small brass fittings makes the job safe and straightforward. Embrass Peerless manufactures an extensive range — straight and angled service valves, chrome isolating valves, flat-faced isolators, washing machine valves and gate valves — all stocked at APM Electricals for next-day trade delivery.

This guide covers the core Embrass Peerless service and isolating valve range: what each type does, where to use it, and which sizes you need to stock.

Service Valves: Straight vs Angled

A service valve (also called a mini-stopcock or quarter-turn service valve) is a small inline valve that allows you to isolate a single supply without shutting off the whole system. They are fitted under basins, behind WCs, on appliance supplies and anywhere a local isolation point is needed. Quarter-turn ceramic-disc operation gives a positive open/shut action with a flat-blade screwdriver.

Straight service valves are used where the pipework runs in a straight line to the fitting — typically along a wall or under a unit where a direct run from pipe to flexible connector is possible.

Angled service valves suit pipework coming from the floor or wall at 90° to the supply point — the most common configuration under close-coupled WCs and pedestal basins where the pipe rises vertically from the floor.

Embrass Peerless straight and angled service valves in 15mm x ½" BSP are chrome-plated brass with a WRAS-approved design, supplied individually and widely stocked across UK plumbers' merchants. The ½" BSP male thread connects directly to standard flexible tap connectors and appliance hoses.

Service Valves — Straight & Angled at APM Electricals

Quarter-turn straight service valve in chrome-plated brass. 15mm compression inlet x ½" BSP male outlet. For isolating supplies under sinks, basins and appliances where pipework runs straight. Screwdriver-operated slot. Supplied individually.

£1.22 inc VAT

Embrass Peerless Service Valve Angle CP 15mm x ½"

Quarter-turn angled service valve in chrome-plated brass. 15mm compression inlet x ½" BSP male outlet at 90°. For WC cisterns, pedestal basin supplies and any application where the pipe rises from the floor. Screwdriver-operated. Supplied individually.

£1.37 inc VAT

Chrome Isolating Valves: 15mm and 22mm

A chrome isolating valve is an inline quarter-turn valve that fits directly into a copper pipe run using compression fittings. Unlike a service valve with a threaded outlet, the isolating valve has compression connections on both sides — it sits in the middle of a run, not at a termination point. Common applications include isolating individual radiators (if no TRV is fitted), feeds to tanks, branch supplies, and anywhere you need to add an isolation point mid-run.

Embrass Peerless chrome isolating valves come in 15mm (for standard domestic branch supplies and radiator feeds) and 22mm (for main feeds, larger radiators and primary circuits). The chrome finish suits exposed applications such as pipework beneath furniture, in airing cupboards or on visible central heating runs.

The flat-faced isolating valve variant has a flat face on one end specifically for connecting to flexible hose tail connectors — used under WCs and on washing machine feeds where a rigid compression run terminates at a flexible hose.

Embrass Peerless Isolating Valve CP 15mm

Quarter-turn inline chrome isolating valve. 15mm compression x compression. Fits directly into copper pipe runs to create an isolation point. Screwdriver-slot operation. Chrome-plated brass body. Suitable for domestic water and central heating up to normal working pressures.

£1.49 inc VAT

Washing Machine Valves

Washing machine (and dishwasher) connections are one of the most common domestic plumbing jobs. The self-cutting washing machine valve is a specialist fitting that allows you to add a dedicated supply tap to an existing copper pipe without cutting the pipe or draining the system — you simply clamp the valve onto the pipe, tighten, and turn the screw to pierce the pipe wall. This makes it ideal for retrofit appliance installations where adding a compression tee would require draining the system.

The Embrass Peerless self-cutting washing machine valve is 15mm x ¾" BSP — the standard fitting that accepts a standard washing machine hose. It is chrome plated and available in standard (bare) and bagged (blister-pack) versions for different trade and retail applications. The 15mm x ¾" tee washing machine tap is the alternative for new builds or full replumbs where you want a permanent tee-and-valve arrangement soldered or push-fitted into the pipework.

Embrass Peerless 15mm x ¾" Washing Machine Valve Self-Cutting

Self-piercing washing machine isolation valve. Clamps to existing 15mm copper pipe — no pipe cutting or draining required. Screw-pierce operation creates a clean saddle connection. ¾" BSP male outlet for standard washing machine hose. Chrome-plated brass body. For cold water supplies to washing machines and dishwashers.

£6.99 inc VAT

Gate Valves: 15mm, 22mm and 28mm

Gate valves are the traditional shutoff valve for domestic central heating and cold water circuits. Unlike ball valves, they use a rising spindle with a brass gate that descends to close the flow — they give a partial-flow throttling capability and have been the standard valve for indirect cold water tanks, primary flow and return, and pump isolation for decades.

While lever ball valves (see our valve guide) are now more common for new installations, gate valves remain essential for like-for-like replacements in older properties with indirect systems. Embrass Peerless BS5154 WRAS-approved gate valves are available in 15mm, 22mm and 28mm compression.

Full Range at APM Electricals

The complete Embrass Peerless service and isolating valve range stocked at APM Electricals includes:

• Service valves: 15mm x ½" straight and angled, chrome-plated brass
• Isolating valves: 15mm and 22mm chrome compression, flat-faced 15mm x ½" and 15mm x ⅜" variants, full-bore 15mm CP, angled 15mm CP
• Washing machine valves: 15mm x ¾" tee tap, self-cutting (standard and bagged), angled 15mm x ¾" version
• Gate valves: 15mm, 22mm and 28mm brass BS5154 WRAS, plus 22mm and 28mm pump gate valves
• Draw-off cock: 15mm MT capillary Type A for drain-off points
• Tee isolating valve: Primaflow 15mm CxC tee configuration for branch isolation

All stocked for next-day delivery. Browse the full plumbing range at APM Electricals.

Why Choose Embrass Peerless?

Embrass Peerless is a long-established UK plumbing fittings brand, and their service and isolating valve range is a staple of plumbers' merchants across the country. Key advantages for trade buyers:

• WRAS-approved designs — compliant with Water Supply (Water Fittings) Regulations 1999
• Chrome-plated brass body and compression connections — compatible with standard copper tube
• Consistent quarter-turn operation — screwdriver slot gives a positive open/close indication
• Competitive trade pricing — service valves from £1.22 each, no minimum order
• Wide size range — 15mm through 28mm covering all domestic applications

For trade accounts and bulk pricing, contact APM Electricals — 24 Western Avenue, Acton, London W3 7TZ. Call 020 8702 8080.