Hi Friends! In this blog, I will explain various terms which are
normally used in dealing with air conditioners.
We need air conditioners of different capacities to get required cooling
against harsh summers as well as heating in chilled winters. Room sizes, number
of people residing in, number of windows, direction of sunlight, ventilation
availability and location of room are the points which should be considered
before buying an appropriate air conditioner.
In this article under mentioned terms are clarified for your information:-
Ø Tonnage
Ø BTU
Ø BEE
Ø EER
Ø ISEER
Ø Where you can get tonnage mentioned
Ø Star rating and its calculation method (based on 1.5 Ton A/C)
Ø How to calculate appropriate air conditioner for your room.
Ø How to calculate monthly electricity bill of your A/C
Tonnage
You often hear the word “Ton” while buying an A/C. Most of the
people use this word but they are unable to explain the term what is “Ton”. Normally the term “Ton” corresponds to a
figure equal to 1000 kg but how the same is concerning with rating and unit
describing factor for air conditioners. No air conditioner has such weight as
referred 1 Ton, 1.5 Ton, 2 Ton and sometimes 2.5 Ton too. “Ton” word with
regards to Air Conditioners has been derived from the factor when in earlier days
room cooling was done by converting water into ice. In simplest words, you can say that the
amount of energy needed at per hour basis to make 1000 kg ice within 24 hours
is called tonnage.
This factor is still being used to denote the power of air
conditioners. Either you buy a Window A/C or Split A/C of any brand; you will
be asked the capacity. Now what should
be the required tonnage according to room size, this is explained in
appropriate sub head of this blog.
B.T.U. (British Thermal Unit)
B.T.U is the conventional unit of measuring
power. Every B.T.U is the amount of
energy that you get by burning a simple four inches kitchen match stick. Every B.T.U. is counted equal to 1055 joules,
the modern calculating unit of energy. Each
B.T.U. is capable to increase the temperature of room (closed from all sides)
up to 1 degree Fahrenheit. Normally
every air conditioner is manufactured to generate minimum energy of 12000 BTUs equal to amount that required to make 1 Ton
ice. In other words, 12000 BTUs are
equal to 1 Ton or 12000 BTUs are equal to 1200 watts or 1.2 KW or 1.2 units.
B.E.E. (Bureau of Energy Efficiency)
This is an agency constituted under the aegis of Government of
India, Ministry of Power. Set up of this
agency was done on 01st march 2002 according to the provisions laid
out under Energy Conservation Act 2001.
This agency suggests various ways to conserve the energy and controls
over the electricity disbursing as well as manufacturing units within India. This agency deals with development of policies
to monitor and ensuring energy saving at all level. Major objective of this
agency is to conserve energy and to reduce the intensity of energy to
strengthen the national economic scenario. Energy efficiency of all the electric appliances
like refrigerators and air conditioners is determined by BEE. How much energy is generated by the air
conditioners after consuming input of power is the basis of star rating. BEE has certain norms under which the energy
efficiency of every refrigerator and air conditioner is determined.
E.E.R. (Energy Efficiency Ratio)
E.E.R. stands for Energy Efficiency Ratio. This is a simple calculation that is based on
input and output of power consumption. This
formula is quite simple. For making
concept clear, I am taking the example of 1.5 Ton A/C.
Formula: Output energy divided by input power. (Output / input) both the
units in watts. In case an 1.5 Ton A/c
generates output power of 5295 watts and consumes 1954 watts, then the calculation of EER will
be as under :-
= Cooling capacity/Power consumption (both in watts)
= 5295 / 1954 = 2.70
Such air conditioner has the Energy Efficiency Ratio is 2.70. This EER is one of the major factors in
determining star rating.
I.S.E.E.R. (Indian Seasonal Energy Efficiency
Ratio)
This stands for Indian Seasonal Energy Efficiency Ratio. Very simple, this ratio is calculated on the
total amount of heat removed by the equipment during the year and total power
consumed to generate this energy. ISEER can vary depending on the climatic
conditions. This is one of the essential
factors associated with air conditioners and I explained the same for your easy
understandings. ISEER varies for every
year based on climatic conditions.
Where you can get tonnage mentioned?
Tonnage of air conditioner comes under technical specifications
and naturally the same will be available on the label fixed on the back of your
machine. To check the actual capacity of
your air conditioner, you can see the technical specifications mentioned on
label. Different Alphabets are used as
Prefix letters and then coded form of tonnage is mentioned followed by other
letters as suffix. This is the jumbled
graph where you can get a dodge. For
your simple understanding, I am showing you some examples of tonnage of Samsung
Air Conditioners.
AR12C5UAEB AR18FC3TAUR AR24FC2UAE
(12000 BTUs = 1 Ton) (18000 BTUs = 1.5 Ton) (24000 BTUs = 2 Ton)
The above figures may be lower if you are buying an air
conditioner of different capacities.
Star rating and its calculation method (based on 1.5 Ton A/C)
Star rating shows energy efficiency of air conditioner. Though the price of air conditioners which
are having higher star rating is normally higher at the time of purchase but
these ACs save your electricity bill more than their cost at later stage.
|
STAR RATING
LABEL SHOWS ITS DETAILS
|
 |
|
EER
|
Star
rating
|
|
2.5
|
1
|
|
2.7
|
2
|
|
2.9
|
3
|
|
3.1
|
4
|
3.3
|
5
|
How to calculate appropriate air conditioner for your room
Deciding suitable air conditioner
for your room size is quite simple. You
need to calculate the dimension of your room where you need air
conditioner. To make the calculation
easy, just take the measuring unit in feet.
Multiply all the dimensions with each other and then divide the same by
1000 to get the tonnage of required air conditioner. In case your room is having length of 10 ft,
breadth 10 ft and height 12 ft.
Requirement of air conditioner for this room will be as under:-
= Length x Breadth x Height / 1000
= 10 x 10 x 12 / 1000
= 1.2. It means you need air conditioner of 1.2 Ton
capacity. As such companies are
manufacturing 1 Ton, 1.5 Ton or higher capacity air conditioner, you should buy
1.5 Ton A/C. In this room size, 1 Ton
A/C will also suffice your requirement.
Now based on this formula, you can
calculate tonnage for other rooms or halls.
Direction of sunlight should also be accounted while calculating tonnage
of air conditioner. Numbers of windows
available in your room and number of people residing in the room are essential
points as these things matter for determining the appropriate air conditioner.
|
Air Conditioner Tonnage requirement
calculator / Chart for room
|
||||||
|
Ser. No
|
Length of room*
|
Breadth of room *
|
Height of room *
|
Total L*B*H
|
Divided by 1000
|
Ton required
|
|
1
|
9
|
9
|
9
|
729
|
0.729
|
0.75
|
|
2
|
9
|
9
|
10
|
810
|
0.81
|
0.75
|
|
3
|
10
|
10
|
9
|
900
|
0.9
|
0.75-1
|
|
4
|
10
|
10
|
10
|
1000
|
1
|
1
|
|
5
|
11
|
11
|
9
|
1089
|
1.089
|
1
|
|
6
|
11
|
11
|
10
|
1210
|
1.21
|
1-1.5
|
|
7
|
12
|
12
|
9
|
1296
|
1.296
|
1-1.5
|
|
8
|
12
|
12
|
10
|
1440
|
1.44
|
1.5
|
|
9
|
13
|
13
|
10
|
1690
|
1.69
|
1.5
|
|
10
|
14
|
14
|
10
|
1960
|
1.96
|
1.5-2
|
|
11
|
15
|
15
|
10
|
2250
|
2.25
|
2
|
How to calculate monthly electricity bill of your A/C
If you are using 1 Ton air conditioner it means your A/C consumes
1200 watts of power. (This comes from
12000 BTU = 1200 watts or 1.2 KWH or 1.2 units). Now if your daily use of air conditioner is
for 7 hours, the usage of electricity will be as under:-
= 1200 x 7 = 8400 watts or 8.4 KW.
The use of air conditioner may vary on day to day basis but
calculation of electricity will be according to above mentioned formula only.
If your air conditioner is of 1.5 Ton, simply the usage of
electricity will be of 1800 watts and 2400 watts for a 2 ton air conditioner
and so on.
You need to multiply the watts from the hours of daily usage and
divide the same from 1000 to get the exact KW. Each KW is equal to 1 unit. You can calculate your monthly electricity
bill on this formula.
Take example of 1 Ton A/C.
Suppose, you use air conditioner for all the days in Aug (31 days) for 7
hours a day, you calculation will be as under:-
= 8.4 x 31 = 260.4 KW per month. (Here 8.4 KW come after calculating 1200 x 7 =
8400 watts or 8.4 KW)
= Suppose rate of domestic electricity is in your area is Rs. 5
per unit. You monthly bill will be as
under:-
= Monthly consumption of electricity units multiplied by rate of
electricity per unit.
= 260.4 x 5 = Rs. 1302.00 per month.
The above mentioned
calculation is only example. You may get
different values according to actual use and rates of electricity of your area.
You can take help from the below
mentioned table to calculate your electricity cost and savings in bill per
month. This table is based on 1.5 Ton
air conditioner irrespective of Window or Split A/C.
|
Star rating
|
EER
|
Cooling capacity
|
Power input
|
Daily unit consumption
|
Elect cost per day
|
Elect cost per month
|
Savings per month
|
|
1
|
2.7
|
5200
|
1926
|
15.41
|
100.15
|
3104.71
|
0
|
|
2
|
2.9
|
5200
|
1793
|
14.34
|
93.246
|
2890.336
|
214.40
|
|
3
|
3.1
|
5200
|
1677
|
13.42
|
87.2004
|
2703.32
|
401.39
|
|
4
|
3.3
|
5200
|
1575
|
12.60
|
81.90
|
2538.90
|
565.81
|
|
5
|
3.5
|
5200
|
1486
|
11.89
|
77.27
|
2395.43
|
709.28
|
|
It is
assumed that you are using your air conditioner 8 hours per day and
electricity cost in your area is Rs. 6.5 per unit. Actual electricity cost may vary. This
calculation is based on standards test procedures observed by BEE.
|
|||||||
Star rating plan that has been formulated by BEE from 29/06/2015
till the calendar year ending on 31/12/2017.
|
Star rating
|
Minimum ISEER
|
Maximum ISEER
|
|
1 Star
|
3.1
|
3.29
|
|
2 Star
|
3.3
|
3.49
|
|
3 Star
|
3.5
|
3.99
|
|
4 Star
|
4.0
|
4.49
|
|
5 Star
|
4.5
|
I hope the above mentioned information is sufficient to give you a
detailed view of air conditioners. Just
rush to market and buy as per your requirement. Best of luck!!
