Choosing The Right Unit
When choosing which is the best unit to have installed in your home, there are three important factors which will influence the choice.
- Budget
- Room Size (heat load)
- Type of system
Budget
Budget is obviously a main concern for most people, but it should not always be the deciding factor. With air conditioning, as with most things, you get what you pay for. Systems which appear to be cheap, are not always so. The cheaper systems are normally produced using lower quality parts. With this in mind they tend to be less reliable and less efficient than more "expensive" systems. However, that is not to say that they should be avoided. In some cases these types of systems are an obvious choice. For example, for people with holiday homes, who may visit 6 weeks of the year and maybe use the air conditioning for 2 or 3 weeks of there visits. The cheaper systems make sense as they will not have much use. For residents or villa rentals, these types of systems would work out to be quite expensive in the long run, so maybe not such a cheap deal after all. Another issue is durability. The weather in the Canary Islands can be extreme and this affects the air conditioning. Most of the top manufacturers have moved to using plastic casings on their outdoor units, rather than metal. The cheaper units tend to be metal casings, which can rust quite quickly in the salty air and strong winds we have here. The top brands also offer a special treating on the heat exchanger to prevent corrosion. This is also true on some of the cheaper brand units. Heat exchanges (the metal fins at the rear of the outdoor unit) which have been coated will have a blue tinge to them. Heat exchangers which have not been treated will be silver or grey.Heat Load
Heat load is the most important factor. Not only should the room dimensions be taken into account, but anything that adds heat to the room. This could be windows, roof/wall structure, computers, fax machine, anything that creates heat, even people. A system must be sized correctly to operate properly. If the system is too big then it will not be able to maintain a comfortable room. There will be temperature sweeps, varying depending on how over-sized the system is. Compressor failure is much more likely to occur as the system will be switching on and off more regularly. This will be more noticeable when the unit is heating and the room will constantly feel hot/cold. There are also health risks with a system that is oversized. Drying of skin, mouth and eyes (especially bad for contact lens wearers) will occur. In extreme cases people can suffer regular static shocks from touching items in the room. An undersized system is not as bad, but still not a good thing. If a unit is too small then it will struggle to meet the desired room temperature and operate constantly, burning unnecessary energy and money. It adds extra strain on the components (especially the compressor) which will lead to a greater chance of failure. A correctly sized system will make a room comfortable. The room temperature should reach the desired temperature and remain there. There should be little or no temperature fluctuation in the room once the set point has been reached. An inverter system is much better at that this level of control and should definitely be a consideration.Types Of System
There are many different styles of indoor units, wall mounted, ceiling mounted, floor mounted, ducted and cassette. The right unit will depend on available space and personal choice. Wall mounted units are the most common choice and they vary in appearance.. Most of the top brand companies offer a few different styles to help keep the appearance of the air conditioning with the room decor. There is not always available space for a wall mounted unit so an alternative most be found. In this case floor mounted, ducted, ceiling mounted or cassette units are useful if space permits. There is not a best style of system. It all depends on the room and available space. Below is a table to show the difference in power consumption and efficiency of many of the common brands in the Canary Islands.| Make | Model | Power Consumption | Cost per Hour |
|---|---|---|---|
| Daikin | TXS25G | 0.55kW | 0.06€ |
| General | ASG9Ui | 0.62kW | 0.07€ |
| Samsung | SH09BPD | 0.7kW | 0.08€ |
| Daitsu | ASD9U | 0.82kW | 0.09€ |
| Atlantic | ASM9RH | 0.99kW | 0.11€ |
From this you can see that the Daikin units cost almost half as much to run than the Atlantic systems. There are systems with even higher running costs than the Atlantic units. We would strongly recommend that any unit installed should have an Energy Efficiency Rating (EER) of A. This applies to any system with a cooling capacity of 5kW and under. All the of the units above, with the exception of the Atlantic system, has a energy rating of A.
