we offer a full range of systems
Comfort are members of the HVCA (Heating and Ventilating Contractors
Association). HVCA are the industry body. 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 do not sub-contract
this as we are the specialists in our field. We often provide
this service to other contractors because we have the expertise.
We can provide any equipment from any manufacturer and some
of those we recommend are - - Daikin, Toshiba, Sanyo, 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
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
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
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 R22 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.