We offer a full range of systems
Comfort are approved and accredited by numerous qualifying bodies and are both registered and qualified, using only skilled, professional engineers. As such we guarantee to offer impartial advice as to selection of equipment and systems. We are approved by most major manufacturers to design, supply, install, service, commission and maintain their equipment, and we use all of our own people to do this.
We can provide any equipment from any manufacturer and some of those we recommend are – Daikin, Toshiba, Mitsubishi Electric, Panasonic, LG and Hitachi. Some you may have heard of others perhaps not. Why do we recommend these systems? Well it’s primarily about quality, reliability and cost, but you can opt for alternatives if you wish.
Three main types
Equipment and systems generally fall into three main types, all-air, all-water and all-refrigerant, however, in every case, refrigerant is used as the final cooling source or medium.
Most systems these days are also referred to as air cooled, as opposed to water cooled. That is, the final rejection of heat to external atmosphere is via air, using a dry coil and fans. Water-cooled systems use a cooling tower and if this is not properly maintained can lead to problems with legionnella or legionnaires disease.
All-air systems transfer cooled or heated air from a central plant via ducting, distributing air through a series of grilles or diffusers to the room or rooms being served. It normally comprises the cheapest equipment cost, but is not necessarily easy or cheap to install in a building due to the size of ducting required and the cost to install. It can be a problem to control temperature properly, and the system may be energy inefficient. All-air is generally rated in second place compared to other systems in relation to the amount of energy used to achieve the desired result.
Water based systems use a single chiller plant or chiller plus boiler to produce water which is then pumped around a building to, most commonly, fan coil units; a fan blows air over a coil containing the water, which then cools or heats the room air. The heat rejected from the room to the water is then pumped back to the chiller unit where it is rejected by a condenser to external air. The water is then chilled or heated again and pumped back to the room units.
This type of system is generally the most expensive to install and own, and is classed as the least energy efficient in terms of transfer of energy.
Refrigerant based systems, often referred to as DX (Direct Expansion), are by far the most efficient, cheapest and most energy efficient form of air conditioning and generally operate split or multi-split systems.
Split means that there is a room or area mounted unit, generally a fan coil and an external unit, a condensing unit or heat pump. Refrigerant is pumped around connecting pipework from the compressor in the condensing unit to the room unit (evaporator) where it expands causing a refrigeration effect, the room air is blown across the coil causing cooling.
The refrigerant carrying the rejected room heat is pumped back to the outdoor unit where it is condensed, giving off the heat to outside air via a dry coil and fan. The refrigerant is then compressed into liquid again by the compressor and the cycle continues.
What is refrigerant?
There is often a lot of media attention given to refrigerants, most of the attention being alarmist, but the truth of the matter is that refrigerants have to be used for cooling.
The most common refrigerants now in use for air conditioning are R410A, R134A and R407C. Refrigerants only damage the ozone layer or atmosphere if they are released.
There are now strict controls on the handling, use, and release of refrigerants, so you should ensure that you employ a reputable organisation to install or service your air conditioning.
If you would like more information regarding refrigerants, please contact us and we will be pleased to send you a fact sheet.