Big names like Webasto have played an active part in these developments and, following its launch of the Blue Cool system last year - which has now established itself with Bavaria, Jeanneau, Dufour and many others - the company will continue to do so.

One of Webasto's UK distributors - Keto - told us further developments are on the way and "major changes" are due to be launched to the public at this year's Southampton Boat Show. Keto's Kevin Bartlett remained tight lipped as to what these were likely to be, but the changes sound significant.

James West, Webasto's marine manager, was able to talk us about the C5 solution, which is designed to provide complete climate control. He explained the reverse cycle used in most air conditioning systems is rather ineffective when the water temperature is around four or five degrees.

To overcome this, Webasto has developed a system that includes a water heater that runs at a slightly lower temperature than needed in a normal hot water system. In operation the system senses the outside temperature and, if needed, activates the water heater to boost the heat output.

Although Webasto launched C5 at ExCeL in January, further developments have taken place and the product is now being sold in its final configuration.

By the time this article is published Webasto will have launched a new small hot water system aimed at the sailboat market. "In most cases sailboats don't run their engines long enough to generate enough hot water, " said West, "so we're bringing the MB3 onto the market to provide 'domestic' style hot water facilities for sailboat use.

One thing Keto's Bartlett was only too pleased to tell us about was Thermoduct, a product developed over 14 months by Bartlett and his business partner Toby Hague.

Non-existent

They had noticed that in boats over 40ft heating in forward cabins was almost nonexistent, due to the losses in the ducting system. In some cases, a second system had to be fitted forward to ensure the accommodation stayed warm.

The increase in weight and power consumed was obvious, so they decided to improve on the insulation properties of the ducting system to increase the heat at the vent.

The result of the development work is Thermoduct. The product is made using hypoallergenic materials and is claimed to "double the heat output" at the vent. Quite a claim.

The product has been tried on one boat in the Jeanneau range, and it's now being considered by many other builders, according to Bartlett.

One almost side effect of the increase in thermal efficiency is the reduction of heat being passed to adjacent areas like cupboards, equipment and food stuffs, all of which can be ruined with the excessive heat given off by conventional heating systems.

Thermoduct, which is being marketed under the Webasto brand, is claimed to work with any system and Bartlett told us: "Even if you have an old heater the investment of a couple of hundred quid on some decent ducting with improve its performance considerably."

As seems to be the case with a number of air conditioning and heating system builders, developments would seem to be mostly variations on a theme, with few radical changes taking place.

However, this doesn't mean that there is little of interest happening. New developments associated with specific applications are very much in evidence at the moment. This is the case with Fischer Panda which, although it doesn't have any radically new products currently on offer, has been working on some innovative applications.

Boiler option In recent months the company has installed a couple of air conditioning systems in 55ft+ boats, both of which have required the inclusion of a boiler option to increase warm air output; something not usually done in the UK.

"The normal chilled water system is fine under normal conditions up to early winter, " managing director Barry Fower told us. "But, mid winter and extreme conditions mean the reverse action needs a boost."

The addition of a boiler significantly increases the output of the heater and these two installations have proved successful.

Although new to the UK, Climma, the Italian manufacturer of the units supplied and fitted by Fischer Panda, has now made its 110v 60Hz units available to the UK. As a result, Fischer Panda is now able to supply units to builders supplying the US and other areas that require 110v systems.

This has opened up a new area for the company as these had only been available "across the water", as Fower put it.

Climma has also been continuing, like many others, the move towards "plug and play" electrical circuitry. As a result, maintenance times have been reduced and replacement items are much easier to fit.

Another company that has been developing new products for specific applications is HFL, which has recently brought out a new combined air conditioning and heating unit with a dehumidifier as part of the package.

HFL's sales and marketing manager, Scott Pettifer, said: "We were asked by a customer to produce a unit that could dehumidify during both the heating or the air conditioning cycle."

As a result, the users can not only input the temperature they need, but also the humidity: ideal for applications where crew may be wet and cause condensation when they come into the wheelhouse.

Four week development

Since developing this unit in under four weeks from initial consultation to finished product, HFL has gone on to add this to its normal product range and it's already proving to be of interest to pilot boat operators. HFL has recently received an order for 10 units to be fitted to boats operated by BP.

Despite the continuing demand for air conditioning and heating units for marine applications, the numbers involved don't compare to the demand of the automotive or outdoor leisure industry. As a result, there is a crossover between the products offered in these markets.

Such is the case of the CombiTronic heating unit being launched at the Southampton Boat Show in September by Eberspacher.

The unit was originally designed for the motorhome market, which is said to produce 6,000 new units a year in the UK alone. Globally, this market is thought to exceed 20,000 units, so a unit that sells into these and the marine market has a sizable potential.

The CombiTronic is a combined water heater and heating unit running on both diesel and mains. The unit has been developed in the UK using the German made Eberspacher heating element unit. "The move towards gas power was prompted by the high fuel consumption of some units and the restricted quantities that can be carried by both motorhomes and boats, " said sales manager Vince Lee.

Although Eberspacher has its own air conditioning division the company is working closely with a number of other major manufacturers to produce joint solutions for specific applications.

One example has been the link between the chiller loop system used by Dometic and the Eberspacher heating system to provide a complete heating and air conditioning system.

Dometic has been going through something of a change recently. Just a few weeks ago the Swedish investment bank EQT, which bought the company from Electrolux some years before, sold its shares to a UK investment bank called BC Partners.

"The UK boating business will see no changes, " said Kester Petersson, Dometic's communications manager.

There have been some attempts to merge the warehouse operations; however, this has not, as yet, been completed, he added.

Target the aftermarket

As for the future, Petersson told us Dometic will "aggressively target the aftermarket", something he is personally keen to see and an area he, and a number of other senior managers, feel Dometic has not targeted in the past.

The marine business will continue to operate from Poole with other outdoor products being handled by the Lisbon office. "There would be no large scale structural changes as a result of the new owners, " he concluded.

Advance Yacht Systems of Saxon Wharf, Southampton, import and distribute the Mermaid Marine Air range of air conditioning systems from the USA.

With over 20 years experience, the Mermaid range targets what is says is the most popular type of installation - the self contained unit. In addition, Mermaid Marine Air manufactures a purpose built dehumdifier that can be built in or surface mounted.

As with the aircon units the dehumidifier is made with a stainless steel case that is considerably smaller than domestic units and more efficient than aircon systems running in de-humidifier mode, making these an innovative way to discreetly keep a yacht's interior dry.

The Mermaid units are available in cool only, with electric heat option and reverse cycle. Advance Yacht Systems MD Rod Boreham told us: "The majority of our customers opt for the reverse cycle (RC) type as the European climate lends itself to making use of the powerful heating function provided in RC systems."

The Mermaid range is designed for the marine environment, using heavy gauge stainless steel cases and chassis with an interesting approach to electrical control. The power control system uses straightforward relays, switches and capacitors - no proprietary circuit boards and software.

This, they say, ensures the unit can be maintained by a competent electrician anywhere in the world without needing expensive components to be shipped to the customer.

The cabin control panels are all digital with the option of infra-red remote control. Here Mermaid use panels from standard domestic aircon units configured with a 4-wire set-up.

The reasons for this are two fold says John Trotter - vice president Mermaid Marine Air.

"The domestic market has advanced to produce very reliable devices with the benefit of advanced programmability, which is useful when 'residing' on shore-power, and these control panels are low cost and freely available around the world - again ensuring that if a mishap should occur - a trip to a local domestic aircon store will get you going again."

The principle behind all Mermaid Marine Air equipment is simple design logic, tough construction using high quality components and low cost of ownership.

Today, aircon systems, especially with reverse cycle, have a real value as standard equipment in on-board systems.

They extend and enhance the enjoyment of what represents a significant investment to the owner.

Remember when it was rare for family cars in the UK to have aircon? Now it is almost a necessity.

If yacht builders are concerned about the add-on cost to the final product for features they feel may not have an immediate re-sell value, then they should consider providing provision for aircon systems like the Legend range from the USA as imported by Opal.

"I believe that providing the basic space and ducting, or room for the right duct, for aircon units would be valuable to owners, " said Boreham. "It would give them the option to make that decision later and not worry about the possible disruption to a newly completed yacht. The cost of subsequent retro-fit would also be significantly lower and could be carried out by the boatyard at any time during the build, should the owner change his or her mind, with little or no outof-sequence costs."

Advance Yacht Systems provides a design service for yacht builders that want a to offer a comprehensive yet completely flexible aircon package from concept to justin time kit supply.