Backflow Testing

The device fails silently

A backflow assembly spends its entire life doing nothing visible.

It sits in the supply, passing water in the normal direction, waiting for the one event it exists for: a drop in supply pressure that would otherwise pull water backwards out of a premises and into the public main.

Its internal check valves, springs and relief valve are mechanical parts that wear, corrode and seize. When one fails, nothing changes from outside. Water still flows normally. The premises notices nothing.

The failure only reveals itself at the moment the device was needed, which is too late to be useful.

That is the entire justification for annual testing, and it is a good one.

The certificate is the point

A test that is performed and not filed has not satisfied anything.

Most water authorities require the report by a set date each year, and they follow up with notices, penalties and in some cases supply interruption.

So the job is not finished when the gauges come off. It is finished when the certificate has been submitted to the authority, within the window, by a tester they recognise.

If a device fails, that adds a step rather than a crisis: most assemblies have rebuild kits, and a repair and retest is considerably cheaper than replacement. What matters is that the retest happens in time to still meet the deadline, which is a reason to book testing early in the window rather than at the end of it.