Too hot (obviously)
	Too humid, especially in summer and autumn
	Can’t leave windows open, because of security risk
	Can’t open windows in summer because of pollen/hay fev
	Can’t open windows because of noise disturbance to neighbours (e.g. from music room/hi fi systems)
	Study used as home office, becomes uncomfortable in summer
	Study has PC and other electrical equipment which creates heat problem

(Heat pumps provide heating as well as cooling in the same unit. The heat pump is extremely efficient on the heating operation, having a COP (Coefficient of Performance of up to 5.4 COP of 5.4 means that the system will deliver 5.4KW of heat into the room, whilst consuming only 1KW of electricity, i.e. very efficient compared to, say, an electric fan heater or convector.)

	Far more efficient than any other form of electric heating (because of high COPs, as described above)
	Difficult to extend an existing central heating boiler system, e.g. for a conservatory, or extension.
	Difficult to extend an existing central heating boiler system, e.g. for a loft conversion (insufficient height for expansion tank)

	Living Rooms
	Studies
	Kitchens
	Conservatories *
	Bedrooms
	Loft Conversions
	Games Room

INVERTER High Efficiency Systems
Inverter technology is now being used on all sorts of electrical products having electric motors. Instead of the motor switching on & off, the Inverter allows the motor to operate at different speeds, depending on the work it is required to do. Most modern air conditioning/heat pump systems now have an Inverter has a standard feature, allowing the compressor motor speed to automatically adjust to the heating or cooling requirement in the conditioned room (which varies considerably during the course of the day). It also allows the motor to start at low speed, so there is no 'spike' in the electricity mains power supply. It also means small systems can be powered from a typical domestic power supply. However, the main benefits to the user are: 1) reduced electricity costs, 2) more stable control of temperature.

Conservatories
Two categories to consider:

For a conservatory of say 4m x 5m, the amount of heat from the sun penetrating the roof and windows in mid summer can be as much as 30KW. To install an air conditioning to cope with this amount of heat would be extremely expensive, and very costly to run, and not very practical. Even with blinds the heat build up can be very high. It would be more appropriate to select an air conditioner which was able to cope with moderate heat gains, and which would provide good comfort levels for most of the time. It is important to obtain advice from an installer when considering this situation.

	The comfort level in this case can be greatly improved by installing a system of about 7KW. It would not be able to cope with the full power of the sun in the middle of summers day, but it would significantly reduce the temperature to a comfortable level for most of the time. It is advisable to ask the installer to select a suitable unit, which will depend on the roof/window area, blinds, shading, etc.
Heating for Conservatories Conservatories usually will also require heating. Therefore a Cooling & Heat Pump system would be ideal in this situation.
Wall Mounted Systems Low cost systems, SRK type, consist of an indoor unit mounted on the wall at high level, which would circulate the air in the conditioned room. This is connected by two small copper pipes to a unit outside, which houses the condenser, fan and compressor (very similar to a compressor in a freezer, but larger). Some units have infra-red controls (similar to a TV remote), others have fixed wall controllers. Other Types of Units Floor mounted units, concealed ducted units, and ceiling suspended units are also available where it is not a convenient location for a wall unit. These systems tend to be more expensive, especially in the case of ducted units, which will require and enclosure, ducting, access panels, and grilles. However, the aesthetic benefits are obvious, as the indoor unit can be hidden from view. Some specialist installers can fit additional controls to ducted systems, to allow for a diversity of cooling/heating in different rooms. Outdoor Unit Location The outdoor unit can be located in the garden or side passage, up to 15 metres from the indoor unit, and must have unrestricted air space. Larger systems have pipe lengths up to 50 metres. It is not possible to install the outdoor unit in a garage, or any kind of enclosure, as it will not be able to dissipate the heat. Outdoor units are fully weatherproof.

Power Supplies
Small systems type SRK, up to 2.5KW can normally operate from a domestic ring main, but it is advisable to check this with the installer beforehand. Larger units will require a separate power supply from the incoming mains distribution board.

Inverter systems type SRK-D (with variable speed compressors) are very efficient, and do not require a high fuse rating (or MCB) for the power supply.

Condensate Drainage
All air conditioning systems when cooling will reduce humidity levels by removing some of the moisture content from the conditioned air. This moisture is collected in a drain tray concealed at the bottom of the indoor unit. The collected water must then be drained away through a small drain to waste, or to outside. Sometimes it is very difficult to conceal the drain piping, or to find a suitable drain connection. Small condensate pumps are available which can deal with this problem, but where possible, it is always better to install a gravity drain.

Installers
3D Air Sales Ltd is not an installer. 3D purchases container loads of air conditioning systems direct from the Mitsubishi in Japan, and has them in stock at its UK distribution warehouse, 3D and HRP supply to installers all over the UK and Ireland, and throughout the HRP Service Centre network.

We know many types of installer, from large national companies (many of which are not interested in small installations), to medium and small companies, some of which specialise in residential installations. Some companies have huge overheads, some do not, which reflects in the installation price. However, 3D is not interested in supplying to cowboys, and will sometimes refuse supply to a so-called air conditioning installer, if they are not technically competent. Air conditioning systems will operate trouble-free for many years if they are installed properly, using refrigeration quality copper piping, and where the engineers follow correct procedures of refrigeration technology.

A good installer will be able to make a survey of the premises, and make calculations to determine the correct size of unit for the application. He/she will check the suitability of the power supply, and discuss with you a suitable location for the outdoor unit. Consideration must be given to any possible noise disturbance to neighbours. Small outdoor units are generally very quiet, but larger units can be a nuisance if operating through the night in a very quiet rural environment.

A good installer will make a neat and tidy job, and clean up afterwards. He/she will explain the operation of the controls, and ensure the purchaser is happy and conversant with the operation of the installed units. Wherever the location, 3D will be pleased to provide the names or two or three installers to quote for the installation.

Important Advice
Do not leave it until mid summer to make your decision, when installers are already working seven days a week. Arrange for a survey to be done in the winter, when there is less demand on an installer’s time.

If you need air conditioning at your place of work (office, shop, hotel, restaurant, gym, club), you can find more information in the Commercial section of our web site. It is interesting to note that thousands of low cost SRK systems are installed in small offices and meeting rooms, where they provide a very comfortable environment for a modest expenditure. Mitsubishi Heavy Industries is one of the ‘big six’ Japanese manufacturers, and is a world leader in the development and manufacture of high quality air conditioning systems. The range extends to large modular multi systems for office buildings up to 10,000m2, and for other commercial buildings.