Afriso Union Fittings Set - DN15 3/4" X 3/4" BSP

DN15 typically refers to the nominal diameter of the fitting, which in this case corresponds to a 1/2" pipe size, but the actual connection threads are 3/4" BSP.

While hand-tightening is possible, a wrench is recommended for securely tightening the unions to the pipework and mixing valve.

Yes, they are rated for a maximum working temperature of 90°C, making them suitable for most domestic hot water and heating systems.

BSP threads are common in many countries. If your existing fittings measure approximately 25mm (1 inch) across the widest part of the male thread, they are likely 3/4" BSP.

The non-return valves prevent water from flowing backward in the pipework, which is essential for maintaining correct flow direction and preventing issues like thermosiphoning or pump damage.

This set is specifically designed for connecting 3-way mixing valves. Compatibility with other valve types may vary.

Check that the flat gaskets are properly seated and that the union is tightened securely but not overtightened. Inspect threads for damage.

Disassemble the union (if accessible) and check for debris or scale obstructing the valve mechanism. Clean gently.

Verify that your pipework has 3/4" BSP male threads. If not, an adapter may be required.