COPs – stop lying, please

When I was at college they taught me all about COPs and EERS. These two measurements give us the efficiency of our equipment divided by 100, so a COP of 3.00 means that for every 1kW of energy I pour into my machine I get 3kW of heat output. Simple.

Now over the years this COP value has crawled upwards. If we look at fairly typical DX equipment in 1992 COPs of 2.5 were common; but by 1998, this had hardly altered despite changing to the evil R407C.

In 2001 the COPs jumped to 3 when DC inverters came in; and current ranges have COPs of 3.8 now that everything is inverter driven.

So it comes as something of a surprise that, despite no major new technological advances being introduced, COPs have continued to increase not at a steady rate but at quite an alarming clip.

The figures are at ludicrous levels now, yet today we reached a milestone: yes, COPs of 10 – amazing!

I saw this in an advert so it must be true.

I can only assume that this is down to our friends in the exaggeration department being let off the leash – someone reign these people in, please.

The Carnot cycle is a theoretical refrigeration cycle used to determine the absolute maximum COP that could be achieved in an ideal system with no losses. No matter what happens this value cannot be achieved, let alone exceeded. A COP of 10 is unachievable in normal conditions unless you work in marketing.

Next thing they will claim is that you can run the units off water!

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