| ||
 |
InspectAPedia® |
|
Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair | Ask a Question or Search InspectAPedia |
 Mobile ViewAIR CONDITIONING & HEAT PUMP SYSTEMS A/C COMPONENTS A/C DATA TAGS A/C - HEAT PUMP CRITICAL DEFECTS A/C DIAGNOSTIC FAQs A/C REFRIGERANTS A/C TYPES, ENERGY SOURCES AIR CONDITIONER BTU CHART AIR FILTERS for HVAC SYSTEMS AIR HANDLER / BLOWER UNITS DIRTY A/C BLOWERS DAMAGED COOLING COIL DIRTY COOLING COIL DIRTY COIL CLEANING PROCEDURES FROST BUILD-UP on AIR CONDITIONER COILS BLOWER FAN CONTINUOUS OPERATION BLOWER FAN OPERATION & TESTING BLOWER LEAKS, RUST & MOLD ADDING A/C: RETROFIT SIZING CLEANING & Legionella BACTERIA COMPRESSOR & CONDENSING COIL, A/C CONDENSATE HANDLING, A/C CONDENSATION or SWEATING PIPES, TANKS COOL OFF HEAT Thermostat Switch COOLING CAPACITY, RATED COOLING COIL or EVAPORATOR COIL COOLING LOAD REDUCTION by ROOF VENTS COMBUSTION GASES & PARTICLE HAZARDS CONDENSATE HANDLING, A/C CONDENSATION or SWEATING PIPES, TANKS DATA TAGS on AIR CONDITIONERS DEFINITION of Heating & Cooling Terms DEHUMIDIFICATION PROBLEMS DEW POINT CALCULATION for WALLS DEW POINT TABLE - CONDENSATION POINT GUIDE DIAGNOSE & FIX AIR CONDITIONER / HEAT PUMP DUCT SYSTEM & DUCT DEFECTS DUCTS - Asbestos DUCT INSULATION, Asbestos Paper DUCT INSULATION for SOUNDPROOFING DUCT SYSTEM NOISES DUCTS, Asbestos Transite Pipe DUST CONTAMINATION FROM HVAC? EDUCATION, HVAC SCHOOLS ELECTRIC MOTOR DIAGNOSTIC GUIDE ELECTRIC MOTOR OVERLOAD RESET SWITCH ELECTRICAL POWER SWITCH FOR HEAT ENERGY SAVINGS in buildings EVAPORATIVE COOLING SYSTEMS EVAPORATOR COIL or COOLING COIL EXPANSION VALVES, REFRIGERANT FAN, AIR HANDLER BLOWER UNIT FAN AUTO ON Thermostat Switch FAN CONVECTOR HEATERS - HYDRONIC COILS FAN LIMIT SWITCH FAN NOISES FURNACES WARM AIR HEATING SYSTEMS GASES, EXPOSURE, TESTING Carbon Dioxide - CO2 Carbon Monoxide - CO METHANE GAS SOURCES GAS MEASUREMENT TOOLS GAUGE, REFRIGERATION PRESSURE TEST HEAT LOSS (or GAIN) in buildings HEAT PUMPS HUMIDITY LEVEL TARGET INDOOR AIR QUALITY IMPROVEMENT GUIDE INSPECTION LIMITATIONS LEED GREEN BUILDING CERTIFICATION LOST COOLING CAPACITY MANUALS & PARTS GUIDES - HVAC MOTOR OVERLOAD RESET SWITCH NOISY AIR CONDITIONER / HEAT PUMP OPERATING COST OPERATING DEFECTS OPERATING TEMPERATURES Air Conditioning System Temperatures Instruments Used to Measure A/C Temperatures Procedures for Making Temperature Measurements PORTABLE ROOM AIR CONDITIONERS PRESSURE READINGS, REFRIGERANT REPAIR GUIDE, AIR CONDITIONERS / HEAT PUMPS REPAIR & DIAGNOSTIC FAQs for A/C REFRIGERANTS GAUGE, REFRIGERATION PRESSURE TEST REFRIGERANT CHARGING PROCEDURE REFRIGERANT DRIERS & FILTERS REFRIGERANT LEAK DETECTION REFRIGERANT LEAK REPAIR REFRIGERANT METERING DEVICES TEVs REFRIGERANT METERING CAPILLARY TUBES REFRIGERANT PIPING & DISTANCES REFRIGERANT PRESSURE READINGS RETROFIT SIZING for A/C or HEAT PUMPS SEER RATINGS & OTHER DEFINITIONS SYSTEM OPERATION OPERATING CONTROLS SAFETY CONTROLS THERMOSTATS, HEATING / COOLING THERMOSTATIC EXPANSION VALVES WATER COOLED AIR CONDITIONERS More Information |
This chapter discusses exactly how and where to measure input and output air temperatures at air conditioning equipment in order to determine whether or not it is operating properly, as part of checking basic air conditioning system operation and for detection of air conditioning operating defects. An introduction to air conditioner temperatures and some rules of thumb that are quick and easy to apply in diagnosing air conditioner problems are provided at the preceding article: Air Conditioning System Temperatures. © Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website. Procedures for Making Temperature Measurements of Air Conditioning SystemsAir conditioner temperatures that are too high or too low can indicate specific operating problems on central and portable or window air conditioners. Simple measurements of air temperatures, if made at the right place, can assist in diagnosing what may be wrong and what repairs may be needed for the air conditioner. This document is a portion of our website which describes the inspection of residential air conditioning systems (A/C systems) to inform home buyers, owners, and home inspectors of common cooling system defects. If your air conditioning or heat pump system has lost its cooling capacity or won't start see REPAIR GUIDE for AIR CONDITIONERS. see How to determine the cooling capacity of air conditioning equipment if the system seems to be working but is inadequate to cool your building. Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution. Refrigeration and Air Conditioning Theory: Refrigeration systems rely on two state changes of the refrigerant: gas to liquid, and liquid back to a gas to move sensible heat from the low side of the air conditioning system to the high side. At the evaporator coil heat (BTUs) is absorbed when the refrigerant evaporates (liquid to gas), and at the condenser coil heat is released during condensation (gas to liquid). R12 refrigerant has a boiling point of -21 degF (change of state from liquid to gas vapor) and R22 has a boiling point of -41 degF. But if you are measuring air temperature close to the evaporator coil or condenser coil you won't record these two temperatures on your thermometer. Rather the temperature that you can record will be significantly affected by ambient conditions. For example, at the evaporator coil the temperature of indoor air entering the coil, the distance between the coil surface and the thermometer, the air velocity, and other factors will produce a temperature reading that is different from and certainly higher than the boiling point of the refrigerant entering the coil. While we may form an opinion about just how cool the air should be right at an evaporator coil, or inside of an air handler supply plenum, most diagnostics look for temperature differences between air entering the air handler and air leaving the air handler to evaluate what's going on in the system. NOTE: an air conditioning technician has more precise tools to evaluate the condition of a system such as gauges to measure the pressures on the high side and low side of the system and an ammeter to measure current draw of the compressor. How to Examine Air Conditioner TemperaturesTemperature Measurements & Observations at the Room ThermostatAir conditioner thermostat settings: observe the settings on the wall-mounted room thermostat (assuming you've already
established that the switches and controls have turned the system on and that it is in cooling mode and has
been operating for half an hour or longer. Temperature Measurements at the Evaporator Coil in the Air Handler How to Measure Air Conditioning Register outlet temperatures using a dial thermometer probe:
we simply wedge the probe of our dial thermometer between the
vanes of a ceiling supply register, or drop it probe-first through the slots of a cool-air supply floor register
where we leave it for at least five minutes. Sketch courtesy of Carson Dunlop. We use tissue or toilet paper to confirm for skeptical owners that
the direction of air flow is "in" at a return register and "out" at a supply register since sometimes this
can be confusing to a novice. Measuring Air Conditioning Duct temperatures using a dial thermometer probe: if there is not an existing duct opening such as a foil-covered hole or a removable plug, we drill a 1/4" diameter hole in the sheet metal of the duct. BE CAREFUL not to drill where you can damage a refrigerant line, coil, wire, etc. After inserting the probe into the hole for measurement, waiting, taking our measurement, we close the hole using a square of adhesive foil tape, duct tape, or snap-in plugs sold for that purpose. Temperature Measurements at the Condensing Coil & Fan/Compressor UnitMeasuring temperatures at an Air Conditioning Compressor: By holding the thermometer's probe in any air path (and patience) it is trivial to measure ambient air temperature, air temperature flowing into the condenser unit at the condensing coils, and temperature flowing out of the condenser at its fan output (keep the probe out of the blades!) Measuring Air Conditioning Temperatures Using an Infrared Thermometer: permits measurement of
surface temperatures such as the surface of a metal duct (is it insulated?), surfaces of
refrigerant suction and high pressure lines (do we know target temperatures?), or surfaces inside
a building. Questions & Answers regarding this article. Ask a Question or Search InspectAPediaHTML Comment Box is loading comments...
Share this Article
... Technical Reviewers & References
Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website. AIR CONDITIONING & HEAT PUMP SYSTEMS
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
|
| Home | About Us | Accuracy | Contact Us | Content Use Policy | Privacy | Website Description | © 2012 Copyright InspectAPedia.com |