Since the failure of an air conditioner to turn on, loss of air conditioner cooling capacity, reduced air conditioning output temperatures, loss of cool air supply, or even loss of air flow entirely can be due to a variety of problems with one or more components of an air conditioner or air conditioning system, after reviewing the lost air conditioner cooling diagnosis procedures described in this article, be sure to also review the diagnostic procedures at each of the individual air conditioning diagnosis and repair major topics listed just below. To return to our air conditioning and refrigeration home page go to AIR CONDITIONING & HEAT PUMP SYSTEMS.
If your air conditioning or heat pump system has lost its cooling capacity or won't start select one or more of the diagnostic articles listed below.
A/C - HEAT PUMP CONTROLS & SWITCHES: air conditioner controls and switches - begin here if your A/C won't start. Here's an important tip: most refrigeration problems, in air conditioners, refrigerators, or freezers, are electrical, not mechanical. In air conditioning school, we used to drive out and collect abandoned refrigerators that people were tossing out during our community's spring cleanup week. Taking these appliances back into the shop we found that almost always the problem that had caused the owner to dispose of their air conditioner or freezer was in an electrical connection or electrical control. So it's worth checking out switches and controls on an air
conditioner before replacing more costly components.
OPERATING DEFECTS: major air conditioning problem symptoms and how to get the air conditioning system working again,e.g. compressor or fan noises, failure to start, and inadequate cool air volume
LOST COOLING CAPACITY: what to do when not enough cool air comes out of the system
What to check first if there is no cool air or not enough cool air
Compressor failure diagnosis: basic checks of the air conditioner compressor
Ducts & Air Handler diagnosis: basic checks of the indoor air handler (blower), air ducts, and filter systems COMPRESSOR CONDENSER: problems with air conditioner compressor/condenser units
DUCT SYSTEM DEFECTS: problems with the air duct system, air filters, supply registers, return air registers A/C REFRIGERANT LEAK DETECTION: how to use a TIF5000 to detect air conditioning refrigerant gas leak REFRIGERANT LEAK REPAIR - how to repair refrigerant leaks in piping, evaporator coils, condenser coils
A/C DIAGNOSTIC FAQs: air conditioning system diagnostic FAQs: Q&A about air conditioner repair - a detailed air conditioning system diagnostic checklist
Books & Articles on Building & Environmental Inspection,
Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
GAS EXPOSURE EFFECTS, TOXIC Toxic Gas Exposure effects, including links to toxic gas exposure screening and gas testing protocols.
Gases: Toxic gases, indoor exposure levels, testing, identification
A Toxic Gas Testing Plan: A Gas Sampling Plan for Residential and Commercial buildings lists some of the toxic indoor gases for which we test, depending on the building complaint and building conditions
Gas Exposure Hazard Levels: for Toxic Gas Exposure to Ammonia, Arsine, Arsenic, Bromine, Carbon Dioxide, Carbon Monoxide, Hydride, Ozone - allowable exposure levels and hazard levels
Carbon Dioxide Gas Toxicity hazard level, poisoning symptoms, & testing
Carbon Monoxide Gas Toxicity hazard levels, poisoning symptoms, & testing
Formaldehyde: US EPA. UFFI (Urea Formaldehyde Foam Insulation) was previously considered a hazard (formaldehyde outgassing). Subsequent research virtually closed concern regarding this material; however formaldehyde appears to remain a health concern for sensitive individuals.
Ozone Warnings -
Use of Ozone as a "mold" remedy is ineffective and may be dangerous.
Sampling for gases in air such as VOC's, MVOC's, toxic chemicals, and combustion products. Unfortunately no single test or tool can detect all possible building contaminants. We use methods and equipment which can test for common contaminants. If the identity of a specific contaminant is known in advance we can also test for a very large number of specific contaminant gases in buildings.
We use gas sampling equipment provided by the two most reliable companies in the world, Draeger- Safety's detector-tubes and Drager accuro bellows pump, the Gastec cylinder pump and detector-tube system produced by Gastec. We also have used gas detection tubes by Gastec previously marketed for use with Sensidyne pumps but Sensidyne pumps now use Kitagawa gas detection tubes. We also use
Sensidyne's Gilian air pump. For broad screening for combustibles and a number of other toxic gases and for leak tracing we also use Amprobe's Tif8850 and 8800, and the TIF 5000 automatic halogen leak detector (for air conditioning and cooling system refrigerant leak detection). All of these instruments, their applications, and sensitivities (minimum detectable limits) for specific gases are described in our Gas Sampling Plan online document.
Radon Gas U.S. EPA Radon level maps ...