Humidity Control Concept
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Humidity Control Concept Hot Gas Reheat, Hot Gas Bypass, VSD & DDC Controls System For DX & CHW Coil By : Best Direction System Ltd. Humidity Control Concept
description
Humidity Control Concept. Hot Gas Reheat, Hot Gas Bypass, VSD & DDC Controls System For DX & CHW Coil By : Best Direction System Ltd. Humidity Control Concept. What is humidity ?. Absolute humidity (g/kg of dry air) Dry air 1.225 kg/m 3 Relative humidity (%RH). - PowerPoint PPT Presentation
Transcript of Humidity Control Concept
Humidity Control Concept
Hot Gas Reheat,Hot Gas Bypass,
VSD &DDC Controls SystemFor DX & CHW Coil
By :Best Direction System Ltd.
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What is humidity ?
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• Absolute humidity (g/kg of dry air)
Dry air 1.225 kg/m3
• Relative humidity(%RH)
Temperature DBTemperature DB
Temperature WB
Temperature WB
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Sensible Heat FactorSensible Heat Factor
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1010 2020 40403030 ooCC00
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1010
2020
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2525
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100100
125125
150150
ooCCKg/kg of dry airKg/kg of dry air
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What is humidity ?
Temperature DBTemperature DB
Temperature WB
Temperature WB
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Sensible Heat FactorSensible Heat Factor
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1010 2020 40403030 ooCC00
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1010
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50%RH
50%RH75%
RH
75%RH100%
RH
100%RH
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Relative Humidity
50%RH
25%RH
25oC 60%RH
25oC 50%RH
DP 16.7oC
DP 13.9oC
100%RH
Psychrometric Chart
Vap Pressure 3.169 kPa
Humidity Effect For Human Being
Appropriated Humidity For Various Application
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HeatingHeatingCoolingCooling
DehumidificationDehumidification
HumidificationHumidification
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Process of the Air
Temperature & Humidity Controls Function
1. COOLING MODE2. HEATING MODE3. DEHUMIDIFYING MODE4. HUMIDIFYING MODE
CONTROLS FUNCTION
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Heat Load Factor
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• Solar Heat Gain• Wall transmission
• Temp. Diff.• No. Of occupancy & Activity
• Activity• Internal heat source
• Electrical power appliances• Infiltration
• ETC.
Heat Load Factor Solar Heat Gain
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Heat Load Factor Wall Transmission
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Heat Load Factor Occupacy Heat Load
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1,000 BTU
1 3 5 7 9
11 13 15 17 19 21 23
Maximum
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20
40
60
80
100
Heat Load Profile
Minimum Maximum
Heat Load Profile
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Hour of Day
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Selected A/C@maximum range
Heat Load Profile (Winter)
Hour of Day
1 3 5 7 9
11 13 15 17 19 21 23
Maximum
-40
-20
0
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40
60
80
Heat Load Profile
Minimum Maximum
Hea
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Hea
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Coo
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System Cooling Load
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• Latent Heat (HL)
Hot Gas Reheat Coil
Hot Gas Reheat CoilEnergy Saving>30%
SYSTEM DESIGN
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Compressor Discharge Gas Temp.H
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Compressor Discharge Gas Temp.
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Hot Gas Reheat Coil
EnergySaving
>30-40%
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Hot Gas Reheat Coil Saving Criteria
With Heater Hot Gas Reheat Coil
Ent. Air (FDB/FWB) 77.6/67 77.6/67
Lvg. Air (FDB/FWB) 43/42.2 43/42.2
Heat Transfer (Btu/h) 213,590 213,590
EE Consumption (kW) 17 17
EE Consumption Average 60% (kW) 10.2 10.2
Ent. Air (FDB/FWB) 43/42.2 -
Lvg. Air (FDB/FWB) 58.8/- -
Heat Transfer (Btu/h) 81,900 -
Using EE Consumption (kW) 24 0
EE Consumption Average 25% (kW) 6 0
Ent. Air (FDB/FWB) - 43/42.2
Lvg. Air (FDB/FWB) - 58.8/-
Heat Transfer (Btu/h) - 81,900
EE Consumption (kW) - -0.47
16.2 9.73
38,491.20 23,118.48
- 15,372.72
- 184,472.64
- 40%
- 9,223.63
He
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A/C Unit Capacity 213,590 btu/h
Co
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g C
oil
Description
Remark : Based on operating 24 hrs/day, Average electrical energy cost 3.3 baht/kWh.
Energy Saving Competitive 'Carrier' Model : 50BY020
Total EE Consumption (kW)
Average Annual Saving/Ton
EE Bill (Baht/month)
Monthly Saving
Annual Saving
% Of Saving
0.00
100,000.00
200,000.00
300,000.00
400,000.00
500,000.00
1 2
Heater
HGR
Annual Energy Cost
Hot Gas Bypass System (HGBP)Prevents often of compressor cycling on/off and maintains
a very constant of humidity control level.
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Hot Gas Bypass System
Completted Refrigerant CircuitCONDENSING UNIT
Check Valve
Hot Gas Bypass Regulator 3-Way Valve
Suction Line
Hot Gas Line
15 m Max.
Liquid LineLiquid Line
Evaporator coil.
Condensatetray / drain
Condensate /Humidifier Drain
380 / 3PH /50 Hz3 PH + N Supply
Reheat coil.
Service Valve
Condensing coil.
Pressure Transducer Control
Compressor
Filter / Drier
Compressor Suction Valve
Compressor Discharge Valve
Temp. Sensing Bulb
Solenoid Valve
Expansion Valve
Suction Accumulator
LEGEND
D
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FAN COIL UNIT
S
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Refrigerant Diagram
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Controls System
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Controls System
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AdvancedControls System
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Advanced cooling capacity management
with compressor & fan variable speed control drivelets us manage widely range
of system partialheat load 40%-100% without recycling of
compressor.
Saving by Nothing to Invest.
Reheat Application For Chilled Water System
Hosp
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VFD Retrofit Consideration
Refrigerant Side
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VFD Retrofit Consideration
Refrigerant Side
Recommended Frequency Range
30-60 Hz
Hermetic/Semi-hermetic reciprocating compressors
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VFD Retrofit Consideration
Refrigerant Side
• Refrigerant piping sizing to improve capacity at minimum and maximum speed.
• High suction superheat gas <25oC.• Compressor oil reclaim system.• Refrigerant flood back to compressor.• Maximum and minimum capability of each compressor type
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Controls “POINT”
CONTROL POINT DIAGRAMFOR BSL-3 LABORATORY FACILITY
DATE : 15-SEP-2003
?2 ?C
?10 %rh
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Controls System
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Controls Network Diagram (Option)
Controls System
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Room Temp. & Humidity ControlsB
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Conventional Air Conditioner
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Room Temp. & Humidity ControlsB
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Air Conditioner with Humidity Control System
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