On Fri, 15 Jun 2007 18:46:57 +0100, "Pete @ www.GymRatZ.co.uk"
wrote:

Just a quick one.
I have had a spam about an airconditioning unit which I wouldn't
normally read, but one claim interested me...

"1.3 kW input power spent you get 3.9 kW of heating / Cooling Output"

How can they make such claims?

Cheers
Pete

Illegally.

I also got some e-mails saying "extend your penis by 1 inch" - "make
love all night - satisfaction guaranteed" - "we guarantee to double
you money" ...................

The word "spam" in your OP could be a clue.