How do you do air conditioning calculations on the capacity of air conditioner for your room? This calculation is important because if done wrongly, you will end up installing an oversize or undersize equipment. An oversized air conditioner is not good as the compressor will run and stop regularly and not able to cool the room uniformly. It will also cause discomfort to the occupants as the dehumidfication of the room is not properly done. On top of that, the electricity bill will be high as the compressor turns on and off too often.Every time the on/off type of compressor starts to run, its power consumption is 6 times higher than when it is running steadily.The cycling on and off of the compressor will lead to shorter life span of the compressor besides having to spend more on the unit price and installation cost.An undersized unit will not be able to cool the room properly and more so if the weather is hot.Cooling capacity for a room is defined as the heat load in a room that have to be removed in order to achieve a certain room temperature and humidity.

The typical design is set to 24°C temperature and 55% Relative Humidity. Study shows that this combination of temperature and RH is the most conducive for the human body. The unit used to measure heat load is BTU/hr. 1 BTU/hr is the heat energy needed to increase 1 pound of water by 1°F.When choosing an air conditioner, usually a 1 HP (horse power) equipment is able to remove 9,000 BTU/hr of heat. With better technology, some machines are able to remove 10,000 BTU/hr of heat with the same capacity. The higher the listed BTU/hr, the greater the cooling capacity.Air Conditioning Calculations - Rule Of ThumbCalculating the cooling capacity needed for your room is a complicated process as there are many factors to consider. However, there is a simple rule of thumb that you can use to estimate the required cooling capacity for your room. Use this result to compare with the calculation done by the air conditioning contractors for your own checking purposes. Find the volume of your room in cubic feet.

This is done by measuring the length, width and height of the room in feet and multiply all the three dimensions together.Volume = Width X Length X Height (cubic feet)Multiply this volume by 6.C1 = Volume X 6Estimate the number of people (N) that will usually occupy this room. Each person produces about 500 BTU/hr of heat for normal office-related activity. Multiply this two figures together.C2 = N x 500 BTU/hrAdd C1 and C2 together and you will get a very simplified cooling capacity needed for the room.wall unit air conditioner 18000 btuEstimated Cooling Capacity needed = C1 + C2 (BTU/hr)Air Conditioning Calculations - Other FactorsOther factors that your contractor will consider to determine the sizing of the cooling capacity include the direction of your room. carrier rooftop hvac unitIf the room is facing east or west, additional capacity is needed as it will be exposed to the morning and evening sun compared to a room that faces north or south.furnace blower motor life expectancy

If the lighting of the room emits a lot of heat, additional capacity is needed. If electrical appliances that generate heat is used, additional capacity has to be factored in.The type of material of the room and windows are also important consideration. Related Topics SEER Calculation Learn what is Seasonal Energy Efficiency Ratio(SEER) to help you purchase a better heat pump unit.HVAC Softwares There are many softwares in the market that greatly help designers to reduce the product design cycle time.Cooling Load Find the explanation on the basic of cooling load here.Heat Pump COP Get a simple understanding of HP Coefficient of Performance.Btu and Btu/hr Definition See how to calculate Btu, Btu/hr and SI Metrics equivalent.Psychrometric Chart Basic definition and applications of the Psychrometric Chart in HVAC. Back to Air Conditioning Calculations Home PageThe HVAC industry measures the capacity of heating and cooling systems with many different terms. This page presents and defines the

most commonly used terms. A BTU is the quantity of heat required to raise 1 pound of water by 1 degree Fahrenheit. Air conditioner cooling capacity is often measured in either BTUH or tons. 1 ton = 12,000 BTUH. A furnace's output can be measured in several ways. One of those measures is the volume of air that passes out of the furnace and into the ductwork over a predefined span of time. This is a furnace's indoor blower capacity and it is measured in cubic feet per minute (cfm). You may see documentation that refers to the "maximum" capacity as compared to the "default" capacity. The maximum indoor blower capacity represents the furnace's highest setting. The default capacity is the factory setting at the time that the furnace A second and related measure is the amount of heat created by the furnace, measured as British Thermal Units (BTUs) or The number of British Thermal Units per hour that the furnace or boiler consumes when running at a steady state.

when it has finished startup and is running at full power.) Boilers with an input BTUh greater than 350,000 are typically considered commercial boilers. A ton of cooling capacity is the amount of cooling that would be provided by melting a ton of ice. Thus, a central air conditioning system that is rated as a 2-ton system would provide the same cooling as melting two tons of ice per day (24-hour period). A ton is equal to 12,000 BTUs. Thus, a 2-ton air conditioner is equivalent to a 24,000 BTU air conditioner. Technically speaking, voltage is the rate at which energy is drawn from an electricity source. A simple analogy is that voltage can be likened to the pressure of water in a pipe. Voltage is measured in volts. Motors are designed to operate with electrical input within a certain range of voltage. If the electrical input source provides electricity at a voltage outside the specified range, performance is likely to be sub-optimal.