Engineer's Plumbing Blog

Siwei Li
Faulty Solar Anti Frost Protection Valve (FPV) Leaking? Why? And how to Prevent It?

Faulty Solar Anti Frost Protection Valve (FPV) Leaking? Why? And how to Prevent It?

A Solar hot water anti front protection valve FPV can die of debris stuck in the seating seals or

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Siwei Li
BSP Sizing VS Physical Measurement Chart

BSP Sizing VS Physical Measurement Chart

What does 15mm, 1/2", DN15 or BSP mean? Why the thread diameter I measured won't match any of the advertised plumbing thread size? Australian BSP (British Standard Pitch) thread sizes for plumbing valves and fittings are only nominal and not the physical measurement for the thread diameter. This article explains BSP vs the physical actual thread measurements.

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