The H-10103 is a 22mm compression single check valve (non-return valve) in WRAS-approved brass. It allows water to flow in one direction only, preventing backflow and the risk of contamination from reverse flow in potable and heating pipework. Both ends are 22mm compression — no soldering or specialist tools required, just tighten the nuts onto the pipe. MPN: H-10103 WRAS Approved — 1304908 22mm Compression × Compression Brass Body Spring Loaded Technical Specifications Parameter Value MPN H-10103 EAN / GTIN 6970472051258 Connection 22mm compression × 22mm compression Body material Brass Valve type Spring-loaded single check (non-return) Max working pressure 10 Bar Temperature range -10°C to +85°C WRAS approval number 1304908 Gross weight (inc packaging) 0.14 kg Warranty 1 year Key Features Prevents backflow contamination The spring-loaded disc opens under forward flow pressure and closes immediately when flow stops or reverses — blocking any risk of contaminated water being drawn back into the supply. Required by the Water Supply (Water Fittings) Regulations in any installation where backflow risk exists. WRAS approved — potable water safe WRAS approval number 1304908 confirms compliance with the Water Supply (Water Fittings) Regulations 1999 for use with potable (drinking) water. Suitable for cold mains, domestic hot water, and expansion vessel connections. Tool-free compression fitting 22mm compression connections on both ends — no soldering, no heat, no flux. Hand-tighten the nuts onto the pipe and finish with a spanner. Can be installed on copper or plastic pipe using the appropriate olive type. Typical applications: Cold mains feed to unvented cylinders and combination boilers, expansion vessel connections, solar thermal and heat pump cold feeds, pump protection in heating circuits, and any 22mm pipework where backflow prevention is required by the Water Regulations or manufacturer's installation instructions. Installation note: Install with the flow arrow on the valve body pointing in the direction of intended flow. The valve must not be installed in the reverse direction. Do not install where the valve may be subjected to pressure exceeding 10 Bar. Related Products: 15mm Compression Single Check Valve | 22mm Compression Ball Valve | 22mm Compression Isolating Valve | Zilmet Hydro-Pro 2L Potable Expansion Vessel | 3 Bar Inlet Control Group