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A/C Refrigeration
DRILLING A/C PRINCIPLES AND DEFINITIONS
Term | Definition |
---|---|
WHAT IS REFRIGERATION? | ... IS TRANSFER OF HEAT FROM WHERE IT IS UNWANTED TO WHERE IT IS UNOBJECTIONABLE |
WHAT IS THE 1ST RULE OF THERMODYNAMICS? | HEAT IS ENERGY AND CANNOT BE DESTROYED |
WHAT IS THE 2ND RULE OF THERMODYNAMICS? | HEAT MOVES FROM WARMER (HOT) TO COOLER (COLD). THE GREATER THE TEMPERATURE DIFFERENCE (ΔT) THE FASTER IT MOVES. (ΔT=change of temperature or temperature change or [delta T]) |
NAME 5 SOURCES OF HEAT? | 1. LIGHT FROM THE SUN. 2. ELECTRICITY, FROM HEATERS. 3. MAGNETISM, HYSTERIS OF IRON. 4.CHEMICAL MEANS. 5. MECHANICAL MEANS |
IN WHAT FORM IS CHEMICAL HEAT GENERATED? | COMBUSTION |
IN WHAT FOR IS MECHANICAL HEAT GENERATED? | 1. COMPRESSION 2. FRICTION 3. PERCUSSION |
WHAT ARE THE THREE STATES OF WATER? | 1. SOLID STATE (ICE) Minimum molecular movement 2. LIQUID STATE (WATER) Limited molecular movement 3. VAPOR/ GAS (STEAM) Molecules free to move in any direction |
WHAT IS "ABSOLUTE ZERO"? | ... IS A LOW TEMPERATURE VALUE WHERE THERE IS NO MOLECULAR MOVEMENT AND NO HEAT PRESENT -459.7° Fahrenheit. |
WHAT IS TEMPERATURE? | ... IS A MEASUREMENT OF THE INTENSITY OF HEAT. MEASURED WITH A THERMOMETER OR FELT BY TOUCH. |
WHAT IS COLD? | IS A RELATIVE TERM THAT SIMPLY MEANS, THE ABSENCE OF HEAT. |
WHAT ARE THREE METHODS OF HEAT TRANSFER? | 1. CONDUCTION 2. CONVECTION 3. RADIATION |
WHAT IS CONDUCTION? | ... IS THE TRANSFER OF HEAT FROM PARTICLE TO PARTICLE W/O THE MOVEMENT OF PARTICLES. I.e. A heat sink. |
WHAT IS CONVECTION? | ... IS THE TRANSFER OF HEAT BY THE MOVEMENT OF PARTICLES (Usually water or air) |
WHAT IS RADIATION? | ... IS THE TRANSFER OF HEAT BY WAY OF WAVEFORM ENERGY. Such as the sun. |
HOW DO WE MEASURE QUANTITY OF HEAT? | ... WE USE BTUs. (British Thermal Units )TO MEASURE THE QUANTITY OF HEAT |
WHAT IS A BTU? | 1. ONE BTU IS THE AMOUNT OF HEAT USED TO RAISE OR LOWER 1 LB OF WATER BY ONE DEGREE. 2. BY USING THE BTU FORMULA |
WHAT IS SPECIFIC HEAT? | 1.THE AMOUNT OF HEAT REQUIRED TO RAISE ONE LB OF SUBSTANCE, ONE DEGREE 2. MEASURED IN BTUS/LB. 3. SPECIFIC HEAT HAS DIFFERENT VALUES BASED UPON THE SUBSTANCE. Ice, water vapor, water, steam have different values) |
WHAT IS THE SPECIFIC VALUE FOR WATER? | THE SPECIFIC VALUE FOR WATER IS: 1 =1 BTU/LB/DEGREE |
WHAT IS THE SPECIFIC VALUE FOR ICE / WATER VAPOR? | THE SPECIFIC VALUE FOR ICE / WATER VAPOR IS: .5 = .5 BTU/LB/DEGREE |
WHAT IS THE SPECIFIC VALUE FOR AIR? | THE SPECIFIC VALUE FOR AIR IS .24 = .24 BTU/LB/DEGREE |
WHAT IS THE SPECIFIC HEAT FORMULA? | THE SPECIFIC HEAT FORMULA IS: = x LBS OF SUBSTANCE X SHV X ΔTemperature: (0-32), 32°= ΔT I.e. (1)LB of ice X SPV ice (.5) X 32° ΔT= 16 BTUS (ΔT=change of temperature or temperature change {or Delta T]) |
WHAT ARE THE TWO BASIC FORMS OF HEAT? | 1. SENSIBLE 2. LATENT |
WHAT IS SENSIBLE HEAT? | WHAT KIND OF HEAT WILL CAUSE A SUBSTANCE TO CHANGE TEMPERATURE, BUT WILL NOT CAUSE A SUBSTANCE TO CHANGE ITS STATE. |
WHAT IS LATENT HEAT? | WHAT KIND OF HEAT WILL CAUSE A SUBSTANCE TO CHANGE ITS STATE, BUT WILL NOT CAUSE A SUBSTANCE TO CHANGE ITS TEMPERATURE . |
HOW IS SENSIBLE HEAT MEASURED? | SENSIBLE HEAT IS MEASURED IN DEGREES FAHRENHEIT, OR CENTIGRADE WITH A THERMOMETER OR FELT BY TOUCH. |
HOW IS LATENT HEAT MEASURED? | LATENT HEAT IS MEASURED IN BTUs/LB. |
WHAT IS CHANGE OF STATE | ... IS A SUBSTANCE IS CHANGED FROM A SOLID TO A LIQUID, OR A LIQUID TO A SOLID. OR A SUBSTANCE IS CHANGING FROM A LIQUID TO A VAPOR, OR A VAPOR TO A LIQUID |
WHAT IS THE EFFECT OF LATENT HEAT AND TEMPERATURE DURING A CHANGE OF STATE? | ... WILL ALWAYS HAVE A GAIN OR LOSS OF LATENT HEAT AND WITHOUT A LOSS OF TEMPERATURE |
HOW MUCH HEAT WILL IT TAKE TO CHANGE ONE LB OF LIQUID WATER TO VAPOR WATER? | IT WILL TAKE A GAIN OR LOSS OF 970 BTUS/LB OF HEAT AT 212 °. THE LATENT HEAT WILL EITHER BE ABSORBED OR REMOVED TO CAUSE THE CHANGE OF STATE. |
HOW MUCH HEAT WILL IT TAKE TO CHANGE ONE LB OF LIQUID WATER TO SOLID WATER? | IT WILL TAKE A GAIN OR LOSS OF 144 BTUS/LB OF HEAT AT 32°. THE LATENT HEAT WILL EITHER BE ABSORBED OR REMOVED TO CAUSE THE CHANGE OF STATE |
WHAT IS L - HOF | IS THE LATENT HEAT OF FUSION |
WHAT IS L - HOV | IS THE LATENT HEAT OF VAPORIZATION |
WHAT IS L - HOC | IS THE LATENT HEAT OF CONDENSATION |
WHAT IS L - HOS | IS THE LATENT HEAT OF SUBLIMINATION |
THE TYPE OF HEAT REQUIRED TO CHANGE 1 LB OF SOLID TO A LIQUID, OR A LIQUID TO A SOLID. W/O CHANGING ITS TEMPERATURE | LATENT HEAT OF FUSION |
WHAT ARE OTHER NAMES FOR LATENT HEAT OF FUSION | 1. LATENT HEAT OF MELTING 2. LATENT HEAT OF FREEZING |
THE TYPE OF HEAT REQUIRED TO CHANGE 1 LB OF A LIQUID COMPLETELY TO VAPOR, OR A VAPOR TO A LIQUID. W/O CHANGING ITS TEMPERATURE | LATENT HEAT OF VAPORIZATION |
WHAT ARE OTHER NAMES FOR LATENT HEAT OF VAPORIZATION | LATENT HEAT OF EVAPORATION |
THE TYPE OF HEAT REQUIRED TO CHANGE 1 LB OF A VAPOR COMPLETELY TO A LIQUID. W/O CHANGING ITS TEMPERATURE | LATENT HEAT OF CONDENSATION |
THE TYPE OF HEAT REQUIRED TO CHANGE 1 LB OF A SOLID COMPLETELY TO A VAPOR . W/O FIRST CHANGING ITS STATE LIQUID. | LATENT HEAT OF SUBLIMINATION |
WHAT IS THE PSI OF OUR ATMOSPHERE AT SEALEVEL | 14.7 PSI |
WHAT ARE 3 CHARACTERIZATIONS OF "SATURATION POINT" | 1. THE CONDITION WHERE THE REFRIGERANT VAPOR IS IN DIRECT CONTACT WITH THE LIQUID REFRIGERANT 2. OCCURS IN THE EVAPORATOR AND THE CONDENSER, AND IS WHERE THE SYSTEM PRESSURE IS ESTABLISHED. 3. IS THE TEMPERATURE AT WHICH THE SUBSTANCE IS CHANGING STATE. |
WHAT ARE OTHER NAMES FOR SATURATION POINT? | 1. CHANGE OF STATE POINT 2. BOILING POINT 3. BOILING PRESSURE 4. SATURATION POINT 5. SATURATION PRESSURE |
WHAT ARE 3 CHARACTERIZATIONS OF SUPERHEAT | 1. THE HEAT ADDED TO A VAPOR (GAS) ABOVE ITS SATURATION POINT 2. IS MEASURED OR EXPRESSED IN DEGREES 'F' OR 'C', AND IS A SENSIBLE HEAT RISE. 3. THE ENTIRE LIQUID MUST BE CONVERTED TO VAPOR BEFORE IT CAN BE SUPER-HEATED. |
WHAT IS DE-SUPER HEATING? | 1. THE COOLING OF A LIQUID TO A TEMPERATURE BELOW THE SATURATION POINT OF THE LIQUID. 2. THIS WILL BE A SENSIBLE HEAT LOSS AND WILL NOT AFFECT THE SYSTEM OPERATING PRESSURE. |
WHAT IS REFRIGERATION TONNAGE | THIS IS A RATING IN REMOVING HEAT OVER TIME, IN A DAY, AN HOUR, OR A MINUTE |
WHAT IS ONE TON OF REFRIGERATION? | ...ONE TONE OF ICE AT 32° WHEN MELTED IN 24 HRS = ONE TON OF REFRIGERATION |
HOW CAN ONE TON OF REFRIGERATION BE EXPRESSED? | 1. 2000 LBS OF ICE X 144 BTU/LB (LHOF)= 288,000 BTU/ DAY 2. 288,000 BTU/DAY / 24 HRS= 12,000 BTU/HR 3. 12,000 BTU/HR/ 60 MINUTES= 200 BTU/ MINUTE |
WHAT IS AN OLD METHOD FOR RATING HEAT? | ICE MELTING EQUIVALENT (IME) |
WHAT IS ONE IME? | THE REFRIGERATION PRODUCED BY MELTING ONE LB OF ICE IN ONE HOUR |
HOW WOULD IMEs BE EXPRESSED IN REFRIGERATION TONNAGE? | ONE TON OF REFRIGERATION IS EQUAL TO 83-1/2 IMEs |