InspectAPedia®   -   Search InspectApedia

Photograph of  This new compressor was placed directly against a brick wall. One third of its condenser coil cooling ability was blocked. Air Conditioning Compressor Condenser Unit Inspection Checklist for Owners & Inspectors

Air Conditioner Inspection Checklist:

This air conditioning inspection article discusses the how to perform a simple visual inspection of an air conditioning compressor-condenser unit, including links to more detailed air conditioning inspection,diagnosis and repair articles useful in the evaluation of air conditioner compressor noises, hard starting, lost cooling capacity, and detection of a burned out compressor or A/C compressors at or near end of their life.

Maintenance tips including attention to compressor support pads and avoiding air conditioning refrigerant leaks are addressed.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

How do We Inspect an Air Conditioning or Heat Pump Compressor / Condenser Unit:

This Simple Visual Inspection Procedure Can Disclose Damage or Operating Problems

Schematic of an air conditioner compressor unit showing inspection points (C) Carson Dunlop Associates The (usually) outdoor half of a typical air conditioning system is a unit containing the refrigerant compressor and condensing coil. The air conditioning compressor motor is a pump which draws heat laden refrigerant gas from the building's indoor components (evaporator coil and air handler), and compresses the low pressure refrigerant gas to high pressure and higher temperature.

The diagnosis and repair of various defects in the air conditioning compressor/condenser unit are discussed in detail using the links provided at the end of this article .

Here is a little visual inspection checklist that any homeowner or home inspector can perform.

Sketch courtesy of Carson Dunlop Associates, a Toronto home inspection, education & report writing tool company [ carsondunlop.com ].

AIR CONDITIONING & HEAT PUMP SYSTEMS describes the major components of an air conditioning system.

Sketches and photographs are provided, and common defects for each A/C component are listed along with visual or other clues that may suggest a problem or probable failure of each components. We explain how an air conditioning service technician will diagnose certain common air conditioning system failures or defects. We include photographs to assist readers in recognizing 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 COOLING CAPACITY, RATED 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

Air Conditioner Compressor Unit Inspection Checklist for an Air Conditioner Report - Outdoor Unit Observations

Key Air Conditioning or Heat Pump System Diagnostic Articles

 




ADVERTISEMENT





Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

Question: what's inside of a hermetically-sealed compressor unit?

(May 10, 2011) Anonymous said:
what is inside if the air compressor units if you cut them open

Reply:

COMPRESSOR / CONDENSER REPAIR shows what is inside of that sealed A/C compressor motor. There we include illustrations and text.

Question: effects of trees & shade on compressor / condenser units

(June 12, 2011) estelle j. said:
A question which just came up: A large tree was recently cut back which had provided shade for my outdoor condenser which faces southwest. Will the efficiency of the unit be adversely affected by this exposure to the hot uninterrupted summer sun? Your comments will be of great help for someone who obviously is not very knowledgeable. Thanks.

Reply:

Shade and A/C condenser units: good question Estelle. The outdoor condenser indeed has a slightly easier time of it if located in shade, though the units are designed to be capable of functioning in full sunlight. I have not found a source that gives us actual data on the change of system efficiency when shaded. So I'm reluctant to give a "made-up" number guess.

You can do several things to restore shade to your compressor unit such as:

- temporarily install a beach umbrella to shade the unit

- build a pergola or lattice-work cover above the unit

But WATCH OUT - don't put any shade over the compressor/condenser that is so close or closed as to block airflow over the unit.

Most A/C compressor installation manuals will give the required clearances around all sides and above the unit in order that its airflow is not obstructed. If you can't find that information, and if your shade source is at least six feet above the unit you should be OK.

(Apr 26, 2012) kristopheruu said:
that was very helpful

Question: I turned our A/C unit on and it is blowing hot air

(Mar 16, 2012) Jeff said:
I turned our A/C unit on and it is blowing hot air. I checked the outside unit and the fan is on. I was standing by it when it came on, the fan came on first, then a few seconds later I heard the compressor come on, it was humming pretty loud. The pressure line going into the unit was very warm. I checked the coils inside the house, (air handler?) and they were pretty warm also. Could this be the start up capacitor? Thanks.

Reply:

See the diagnostic procedures beginning at LOST COOLING CAPACITY

Question: cutoff valves on AC / heat pump refrigerant lines?

(May 15, 2012) slam jeme said:
please , my condensing unit is carrier but the hot gas by bass has cut off can i install a new compressor whithout unloding capilitily

Reply:

Slam Jeme I haven't seen cutoff valves on refrigeration lines, but if that's what youv'e got it may be that a swap-out ability was what was intended. Just ask your tech how they are going to get all of the air out of the new system and lines during the reconnection process.

Watch out: a shutoff valve on a refrigerant line can prevent proper compressor/condenser operation and may be unsafe to boot.

Question: outdoor compressor fan not running

(June 19, 2012) Evilu Pridgeon said:
The outdoor compressor fan is not turning even though the a/c is running. Air does not seem as strong or as cool as it usually is. Should I turn it off in order not to burn up the motor, or what are my other options? Can it be fixed?

(Sept 18, 2012) Cathy C. said:
The fan on the outdoor condenser is turning, but at a slower speed. The air coming from the top of it is cool, not warm. It makes a sound like a stick being run across a grate periodically as if it's trying to kick into a higher gear. The sound lasts about 3-4 seconds. Indoor runs but air is somewhat cool. Capacitor was tested and checks out fine (it was installed last summer). We currently have it turned off. Any suggestions?

Reply:

Evilu if the outdoor fan is not turning but the outdoor compressor motor is trying to run it sounds like a fan relay or fan start run capacitor problem. TURN OFF the system to avoid damaging it while you wait for repair.

Cathy:

See FAN, COMPRESSOR / CONDENSER UNIT - if the fan on the outdoor compressor / condenser unit is not working properly

Question: condenser stoppd working, jiggled wires and it starts

(Jan 26, 2013) Dooley said:
My condenser stopped working a few months ago there was no noise of it trying to start just nothing at all. The other day I was looking at it and decided to jiggle the wires coming from the blower and the unit started right up and shut down. I jiggles the again and it started right back up. I could see the wire nuts holding the wires together and decided to reconnect them better.

When doing so they came out of the wire nuts. I had a blue and yellow wire coming from the condenser. And a red and white wire coming from the blower. No matter what combination I tried I could not get the unit to work again. And now nothing is working blower, heater, or the condenser. Any suggestions? I have tried all breaker that I know of.

Reply:

Sounds as if in moving wires around you may have blown a fuse or mis-wired the unit. Ask for help from your heating service tech. Meanwhile leave power to the unit turned off for safety.

Question: split system AC display unit blinks on and off

(June 29, 2014) Bapurao said:
After switching on split AC, and starting through Display unit, Display shows for 7 to 8 seconds and off for 4 to 5 seconds. A C unit dosen't work.
Can any expert tell why this happening? or cause of this?

Reply:

Bapuaro

If a display is cycling on and off I'd look for a condition that is causing the system to lose power itself or a loose switch, or an overload causing a system reset.

Question: minimum outdoor temperature for an accurate AC tuneup or freon check

28 Feb 2015 Phylon said:
What is the minimum outdoor temperature for accurate tune up/maintenance/ Freon level check?

Reply:

Pylon

In the inspection points for A/C and heat pumps listed in the article above please see "Temperatures of Operation" where you'll find a link to a detailed article diving operating temperatures and the measurement procedures.


...

Continue reading at A/C - HEAT PUMP CRITICAL DEFECTS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

Suggested citation for this web page

A/C INSPECTION CHECKLIST - OUTDOOR UNIT at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to AIR CONDITIONING & HEAT PUMPS

Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia

Ask a Question or Search InspectApedia

Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

Note: appearance of your Comment below may be delayed: if your comment contains an image, photograph, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Apologies for the delay.

Only one image can be added per comment but you can post as many comments, and therefore images, as you like.
You will not receive a notification
when a response to your question has been posted.
Please bookmark this page to make it easy for you to check back for our response.
Our Comment Box is provided by Countable Web Productions countable.ca

Comment Form is loading comments...

Citations & References

In addition to any citations in the article above, a full list is available on request.



ADVERTISEMENT