What is a BTU?
How do I know what
size is right?
How does an air conditioner work?
Which manufacturer or brand makes
the best airconditoner?
How long
does it take to install?
How
often should I have my unit serviced?
Why
should I have my unit serviced?
How can I
save energy whilst using an air conditioner?
What is a BTU?
BTU is short for British Thermal Unit, and is a basic
measure of thermal (heat) energy. One BTU is the amount of
energy needed to heat one pound of water one degree
Fahrenheit, measured at its heaviest point.
Most heating and cooling systems produce thousands of BTUs,
almost rendering the measurement of one BTU pointless. Air
conditioning units are therefore measured by their BTU's.
Larger and more expensive systems should provide
significantly higher BTUs than smaller ones. When deciding
between similarly priced units, compare the BTU's for a
better gauge of performance.
How do I know what size is right?
This is probably one question of extreme importance
and crucial to having a solution that works!
A system that is too large will cool or heat your house
quickly, but you may not feel comfortable. That's because it
will satisfy the thermostat before it can adequately remove
sufficient moisture from the air during the cooling mode,
leaving you feeling sticky and humid. This could even lead
to moisture and mold problems. And, the stress of
short-cycling (too many starts and stops) will shorten the
life of your equipment and increase your heating and cooling
bills.
On the other hand, a system that is too small just cannot
get the job done, especially in extreme weather conditions.
The air conditioner will run constantly in the summer and
the furnace will do the same in winter.
But a correctly sized system isn't just based on the size of
the structure. Many factors go into determining the size of
the system. Including type of house and walls, type and size
of windows, insulation, basement and attic conditions, house
orientation, and so on. At Cool Air, we ensure that a
consultant visits your home or office in order to ascertain
the correct measurements and therefore suggest the
appropriate unit.
The following is a recommendation of unit sizes vs
room sizes:
| Approximate Room Size: |
Suggested Aircon Size: |
| 15 to 18 m² |
9000 BTU |
| 20 to 25 m² |
12 000 BTU |
| 30 to 35 m² |
18 000 BTU |
| 40 to 45 m² |
24 000 BTU |
| 55 to 60 m² |
30 000 BTU |
How does an air conditioner work?
Air conditioners
and refrigerators work the same way. Instead of cooling just
the small, insulated space inside of a refrigerator, an air
conditioner cools a room, a whole house, or an entire
business. However, there are different measures of energy
(BTU) per unit and therefore the room size must be taken
into consideration in the installation of the appropriate
unit.
Air conditioners use chemicals that easily convert from a
gas to a liquid and back again. This chemical is used to
transfer heat from the air inside of a home to the outside
air.
The machine has three main parts. They are a compressor, a
condenser and an evaporator. The compressor and condenser
are usually located on the outside air portion of the air
conditioner. The evaporator is located on the inside the
house, sometimes as part of a furnace. That's the part that
heats your house.
The working fluid arrives at the compressor as a cool,
low-pressure gas. The compressor squeezes the fluid. This
packs the molecule of the fluid closer together. The closer
the molecules are together, the high its energy and its
temperature.
The working fluid leaves the compressor as a hot, high
pressure gas and flows into the condenser. If you looked at
the air conditioner part outside of a house, look for the
part that has metal fins all around. The fins act just like
a radiator in a car and help the heat go away, or dissipate,
more quickly.
When the working fluid leaves the condenser, its temperature
is much cooler and it has changed from a gas to a liquid
under high pressure. The liquid goes into the evaporator
through a very tiny, narrow hole. On the other side, the
liquid's pressure drops. When it does it begins to evaporate
into a gas.
As the liquid changes to gas and evaporates, it extracts
heat from the air around it. The heat in the air is needed
to separate the molecules of the fluid from a liquid to a
gas.
The evaporator also has metal fins to help in exchange the
thermal energy with the surrounding air.
By the time the working fluid leaves the evaporator, it is a
cool, low pressure gas. It then returns to the compressor to
begin its trip all over again.
Connected to the evaporator is a fan that circulates the air
inside the house to blow across the evaporator fins. Hot air
is lighter than cold air, so the hot air in the room rises
to the top of a room.
There is a vent there where air is sucked into the air
conditioner and goes down ducts. The hot air is used to cool
the gas in the evaporator. As the heat is removed from the
air, the air is cooled. It is then blown into the house
through other ducts usually at the floor level.
This continues over and over and over until the room reaches
the temperature you want the room cooled to. The thermostat
senses that the temperature has reached the right setting
and turns off the air conditioner. As the room warms up, the
thermostat turns the air conditioner back on until the room
reaches the temperature.
Which manufacturer or brand makes the best airconditoner?
Air conditioning is a matured technology so most of the
popular brands work well. Many of them use parts made by the
same manufacturers. So, the main considerations are the
price, warranty, attractiveness, noise, etc. Some
manufacturers offer a 3-5 year warranty on all parts while
others offer only 1 year. Some units are unattractive and
will not compliment your landscaping.
Whatever you decide, the most important consideration is the
installer you use. You may buy the best system in the world
but if it is not properly installed, you will actually be
buying nothing but a big headache for years to come. For
your protection, make sure you use a specialised contractor
such as Cool Air so that our expertise becomes your ease.
How long does it take to install?
This is dependant on the type of unit you choose and the
area in which it is installed. In most circumstances, a
single or twin split application can be installed in one
day, with minimum disruption.
How often should I have my unit serviced?
Heating and Air Conditioning equipment should be serviced at
least once a year. The best scenario is to have the heating
system checked in Autumn and the air conditioning checked in
Spring to ensure durability, longevity and efficiency of
use.
Why should I have my unit serviced?
Annual servicing includes cleaning the system, checking for
any problems or potential problems and adjusting for Peak
efficiency. The benefits include:
• Increased dependability.
• Find potential problems and fix them quickly.
• Provide maximum efficiency which lowers energy costs.
• Prolongs the life-span of the equipment.
• Maintains safe and healthy operation.
• Can help to protect the environment.
• Drastically reduces the chance of a break-down.
Many Service Plans also include extra benefits, including:
• Discounts on repairs.
• Discounts on purchases and future replacement.
• Priority Status for Scheduling.
• Increased warranty duration.
How can I save energy whilst using an air conditioner?
There are some simple things you can do to save energy when
using an air conditioner:
-
Install the air
conditioner (or outdoor unit of a split system) on the shady
side of the building (or shade the air conditioner itself);
make sure the air flow around it isn't obstructed.
-
The temperature of a
heated room in winter should be between 18-21°C while the
temperature of a cooled room in summer should be about
23-26°C (remember the humidity indoors will be low, so it
will feel cooler). The temperature should be checked after
the air conditioner has been operating for 30 minutes. When
a hot day is expected, turn on the air conditioner early
rather than wait till the building becomes hot (it operates
more efficiently when the outside air temperature is
cooler).
-
Keep windows and
doors closed when using a refrigerative air conditioners
(evaporative air conditioners require some air flow). Close
curtains on hot summer days and cold winter nights. Outdoor
shading of windows in summer is most effective. If the
machine has adjustable louvres, adjust them towards the
ceiling when cooling, and towards the floor when heating (as
cool air falls, hot air rises). Follow the manufacturer's
instructions for filter cleaning.
