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Prepared by Joel Talam

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A vapor refrigeration compression

cycle: A review

Evaporator

Condenser

CompressorMeteringdevice

Fan

Fan

Energy in

Energy in

Energy out

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1. EER

2. Noise Level

3. Compressor and Fan Motor Robustness

4. Fast Cooling

5. And Other Features

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1. What is EER?

Energy Efficiency Ratio

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Energy rate(electrical powerinput, w) Energy we

want (rate ofeffect ofrefrigeration,Btu/hr)

MACHINE(Airconditioningunit)

EER

rate of effect of refrigeration inBtu/hr

EER= ----------------------------------------------------------electrical power input in watts

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Experimental parameters

Ambienttemperature95F(35C)

Conditionedroom

80F(26.7C) dbt67F(19.4C) wbt

A/C

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Example:

A 12,000-Btu/hr air conditioner consumes 1,200 watts .Find its EER.

EER = (12,000 Btu/hr)/(1,200 watts) = 10

The higher the EER is, the more efficient the airconditioning unit is. However, a higher EER is usually

accompanied by a higher price.

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SEER - Seasonal Energy Efficiency Ratio

- computed in a normal annual usage- standard depend on every country or state

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2. What is noise level?Air disturbance our hearing can detect. Its sound

power is expressed in decibel (dB)

A/C unit

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0 dB is nearly total silence

a sound ten times more powerful than near total silenceis 10 dB

a sound 100 times more powerful is 20 dB.

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From ASHRAE

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Window type A/C units less than 40 dB

Single package type A/C units less than 75 dB

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3. Compressor and Fan

Motor Robustness

Refers to the reliability of the compressor and othermotors in the unit

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Compressor major failures:1. open windings

2. grounded

3. unusually high current4. mechanical stuck up

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The rate of cooling a space to the desired coldtemperature.

4. Fast Cooling

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Factors to improve the rate of cooling1. velocity of air from the evaporator

2. correct refrigerant charge

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5. And other Features1. Easy Maintenance

2. Health considerations3. Easy to operate

4. Optimizing usage of conditioned air

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Maintenance Easy servicing

Available parts

Simple technologyAvailable manuals

Nearby service centers

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Health considerationsAir filters are disinfectant

Mosquito repellant

Ionizer

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Easy to operate1. Fool proof

2. Simplified remote control commands

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Optimizing usage of conditioned air1. Air louvers

2. Recommendation of A/C location

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What component in an A/C unit can

EER be increased, and how? 15 min 1.

2.

3. 4.

5.

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End of the session

Thank you