GUEST EXPERT

Caroline Oldham

I am a founding director of Advance Yacht Systems, a family business specialising in generators, watermakers and air conditioning systems. The question I often get asked is: I am looking to fit a heater, but when I go to the Med I think I’m going to need air conditioning – can an air con unit provide heat too?

Yes, most modern marine air con units come with reverse-cycle heating as a standard feature. Reverse-cycle heating works well but a note of caution: on any older tech (start/stop type) units, not only will the

energy demand be very high, but the heat output in seawater temperatures below 10°C is likely to be very poor.

However, the arrival of variable frequency drive technology (ultra-low power marine air con) means modern units can produce heat in seawater temperatures as low as 5°C, using such low levels of power that they can be run off a modest inverter and a small battery bank – even away from a marina.

This means that smaller boats can now enjoy the kind of climate control you would experience in most new cars, while reducing the humidity on board at the same time.