Sometimes I sound like a grumpy old man. But people love me for it because they know I care.

I get very grouchy when I come across solar systems at open inspections that aren’t functioning correctly.

We all know now that solar helps sell a house. But it’s worthless if it’s not working properly.

Last year I wrote about “cowboy” installers and older “orphan” systems that couldn’t be repaired because both the installer and manufacturer no longer existed.

Most issues involve low-quality imported parts failing and dangerous installations that create potential fire and electrocution hazards.

My company spends a lot of time repairing or replacing substandard solar systems.

So I tell everyone who asks me for advice about buying a property to check that everything works and that it’s been serviced regularly.

A while back an official national survey found as many as one in four domestic solar systems were defective.

A big problem is direct current isolators that are subject to an industry recall.

Much like the Takaka automotive airbag recall, it has been a slow and painful process to persuade owners to identify if they have a problem.

This gets me really grouchy because you can’t put a price on electrical safety.

The survey also reported many instances of faulty wiring posing an even greater electrocution risk.

A typical example is a cowboy installer using plastic cable ties to secure panel wiring. It doesn’t take a degree in rocket science to realise plastic degrades quickly in summer heat. Next thing: bang, the cable drops onto the hot roof and fuses itself in.

There is an even bigger bang to come when the first winter rains come.

So do me a favour, please. Help me stop being grumpy by taking responsibility and phoning us to check out your older solar system.

We’ll all feel better for it.