A/C or heat pump operating defect checklist FAQs.

This articler series explains how to fix an air conditioner or heat pump that is not operating properly - starting with a simple checkist.

Air Conditioning System Maintenance & Operating Defect Diagnosis & Repair Guide: defect checklist

These questions and answers were posted originally

at OPERATING DEFECTS, AIR CONDITIONING - please check out that article.

On 2016-01-16 by (mod) - Question will increasing the SEER rating 2,3,or 4 points improve efficiency ?

Efficiency yes, airflow perhaps not.

First lets get a correct diagnosis of the problem.

Dirty blower fan, dirty filter, crimped or connected supply duct, inadequate return air, etc.

Fix that and then re evaluate

On 2016-01-16 by David

Old house: Local installer said gas heat was added later, air flow not good, want to replace old gas furnace with new gas/electrial AC unit.
Question will increasing the SEER rating 2,3,or 4 points improve efficiency ?

On 2013-03-17 by Vicki

just turned on the ac to see if all was well,the high pressure line is cold not hot or warm like should be,what is the cause of this? the unit was totally replaced in august of 2010.

On 2013-01-27 by Frustrated Lakes Heat pump/air conditioner and find it makes a banging noise

We have a Lakes Heat pump/air conditioner and find it makes a banging noise when it kicks in or out and it seems to start and stop continually. is this normal?

On 2013-01-12 04:20:04.569205 by john

no heat or a/c ,brakers ok when power switch is first turned on you can hear ducs expanding then quits

On 2012-11-05 18:07:09.151457 by bruce

i cked the breaker box, switched both HP and furance breakers back and forth cked noutside breaker also put thermostat on 63 (inside temp was 59) aux heat came on and warmed house and turned off heat pump did not turn on during next cycle either

On 2012-05-29 16:06:10.484932 by (mod) -

Outdoor:

If the outdoor unit is never coming on your system will not produce cool air. That's because no refrigerant is being condensed to liquid form for routing to the cooling coil inside your indoor air handler.

Make sure the compressor condenser has power, that your thermostat is in COOL mode and is calling for cooling. If the compressor condenser unit (the outdoor unit) makes no sound at all it may have no power or there could be a bad switch or relay.

Complete diagnostics are at LOST COOLING CAPACITY (article link in our ARTICLE INDEX)

On 2012-05-29 by Outdoor Unit

My thermostat and fan are working fine. Air blows through the vent but the house never cools to temp.

The outdoor unit has not come on at all - it is making no noise whatsoever. Reset blower/furnace switch, checked over flow, no condensation being drawn out of the air through the lines.

Getting ready to check to see if I buy new fuses (pull-outs) if that will solve the problem

What else should I look for next? I am not even sure if I can tell if a fuse is blown. I have two pull-outs with two fuses each... not sure how much they cost. Just had gas added last year and cleaning, service.

The unit is not that old, estimated at 8-10 years.

On 2012-05-20 15:32:55.657595 by lester

my fan will come on in the heat mode but not the ac mode .I just raplece the thermostat board as the drain was clog and the board got wet. it work fine for two weeks now i have this issue but the drain is clear and no water in the pan what can i do?

On 2011-10-19 23:44:00.172494 by Steve

my air cond heats great but cools poorly at the heat of the day. Everything is clean and maintained well

On 2011-07-19 15:59:43.866578 by (mod) -

Molly:

First, your condensate system needs to be one that empties automatically, either by draining by gravity or by using a condensate pump.

Next, it sounds worth looking into why you have so much condensate and whether the amount is really abnormal - it depends on the relative humidity where you live and of course building specifics.

If there were a source of water leaks or humidity in the building that needs correction you'd want to find and attend to that too.

On 2011-07-19 03:02:45.440141 by Molly

Help, we have had out unit "fixed" each summer. We have tons of water coming out of our overflow pipes, instead of coming out of the main drains. It is filling up a 5 gallon bucked with the overflow pipes at least 3 times a day.

They cleaned the whole unit last year, found some blockage, and had to replace the motor fan last year as well. Frustrating since the unit is a Lennox, and only 5 years old.

On 2011-07-06 17:08:35.022520 by (mod) -

Carolyn: your compressor/condenser may be overheating; check to see that it's airflow is not blocked, it's not too close to the building;

if you can cool down the outdoor unit with a water spray and you see that that gets it going, the system is overheating - could be an installation error (as I just described above) that blocks air flow, or the system compressor could be failing.

On 2011-07-06 17:07:17.729842 by (mod) -

David: take a look at the diagnostic procedure aricle found in our ARTICLE INDEX and titled LOST COOLING CAPACITY for help in explaining why you are not seeing cool air out of your supply vents - I'm presuming you're trying to run your system in cooling mode.

On 2011-07-06 00:23:46.966357 by David R Barnes

my air blows warm air out the vents, everything is running. Heatpump blows cool air out of top of unit, not hot air.

On 2011-07-03 14:59:23.553149 by Carolyn

My air works, then stops and the house heats up. If I turn the air Off, then On, it starts working again. What can I check or do?

On 2011-06-01 16:53:21.220944 by (mod) -

Sean, about that E-8 code, I am guessing that you are referring to a diagnostic code for your air conditioner, read out on an LED/LCD display? If so you'd need to take a look at the table of codes in the service manual for your brand and model unit.

If you don't have the installation and service manual, given the brand, model, and serial number (all available on your unit's data tag) you can usually find the information online. If you are having trouble finding a manual let us know (see the CONTACT link at page bottom) and I'll help look.

On 2011-05-31 16:41:14.249686 by (mod) -

If your air conditioner is not working at all, that is, it won't turn on, start at
the articles in our ARTICLE INDEX titled CONTROLS & SWITCHES and see THERMOSTATS. Be sure power is on and that the thermostat is set to a temperature below room temperature, and is in "cool" mode.

On 2011-05-31 01:39:09.475677 by billy

unit not working at all

On 2011-05-29 03:46:18.288123 by sean

my unit is only saying e8 what does that mean

On 2011-05-03 00:04:54.634863 by (mod) -

I think you want to look at the article found linked to in our ARTICLE INDEX titled LOST COOLING CAPACITY

On 2011-05-02 20:22:23.052213 by Herbert Bray

Sorry, it's not puling hot air out of the house only cool air..

On 2011-05-02 20:21:02.843435 by Herbert Bray

My AC unit is running and the fan is turning but it's pulling hot air out of the house omly cool air.
The inside temputure is not coming down, I have clean filters and the outside unit is not dirty.
Does anyone know why it's not working properly?
I have a Coleman 4 ton heatpump

Question: Carrier 38 YXA Repair

x(May 14, 2014) james said:
My airconditioner is working on the inside but not working outside...lost its cooling capacity. When I checked the main panel, the breaker tripped, when I went outside to check on the fan, it wasn't working, removed cover and checked the capacitor,

the "HERM" blew and the blue wire was burnt, the outside switch with the fuse, when checked, 1 fuse blew up.
I changed all the fuses on the outside switch and placed a new run Capacitor..

.I put it back on, the fan started turning but the condenser/compressor just made a humming sound and tripped the circuit breaker again and blew the 2 pieces of fuses on the outside switch...also installed a new contactor but same things happened over and over.

I just don't know what to do anymore. My unit is a carrier 38yxa. 11 years old. Any assistance you can help me regarding this matter is greatly appreciated.

Reply:

James this is a problem for an experienced hvac tech and a service call. It sounds as if your compressor condenser had a failed compressor motor or possibly a control board or a fan motor.

...

Continue reading at OPERATING DEFECTS, AIR CONDITIONING or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Defects Lists for Air Conditioners & Heat Pumps

• DEFECTS LIST - AIR CONDITIONING
  • A/C - HEAT PUMP CRITICAL DEFECTS
  • A/C INSPECTION CHECKLIST - OUTDOOR UNIT
  • A/C INSPECTION LIMITATIONS
• DEFECTS LIST - HEAT PUMP
  • DEFECTS LIST - HEAT PUMP SUBSYS
• DUCT SYSTEM DESIGN SIZE & DEFECTS
• OPERATING DEFECTS, AIR CONDITIONING

Suggested citation for this web page

OPERATING DEFECTS, AIR CONDITIONING FAQs 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

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