Need Hvac tech help for house ac short cycling

Hey rollers my outdoor ac compressor is cycling on and off every 10 seconds and my guess was that the ac being new within last 6 months that it was oversized for my space to start with, or maybe low refrigerant. Outside copper pipe was cold when it started short cycling but seems warm now(it's off). Is it wise/safe enough for a novice to troubleshoot this alone?

bro54209 said:

Hey rollers my outdoor ac compressor is cycling on and off every 10 seconds and my guess was that the ac being new within last 6 months that it was oversized for my space to start with, or maybe low refrigerant. Outside copper pipe was cold when it started short cycling but seems warm now(it's off). Is it wise/safe enough for a novice to troubleshoot this alone?

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It could be a low level of freon

if it is newer R-410A , you may have a leak .....make a soapy water solution and whilst running spray the solution over the fittings and any other coolant lines ..if you see bubbles ...yeah

oh, is the air coming out of your registers cold?

check the fins of the coils and what not..are they clogged?


What is the SEER rating of your AC Unit

oh , here is another thing , right above your furnace where the big s
rectangular metal duct comes out....there are evaporator coils ... they may be clogged too

The insulate pipe was cold when I turned the ac on and it ran solid without short cycling for like 30 minutes as if no problem, when I tried this afternoon but stayed at 78 degrees when set at 72 the entire time, yet blowing cold air from the vents into the room. After turning the power off several times, forgetting about the ac, I went into the attic to troubleshoot a neutral wire broken on a daisy chain circuit to find this... After securing the loose duct, the air blowing in the room magnified 5x and way cooler, but went back to shorting every 5 seconds before the outdoor unit can get any flow. Would spraying water with any regular dish soap on the coolant fittings the way to go to test leaks? I need to find where the evaporator coils and fins to check if they're clogged and I'm not sure where the seer rating is. Least I think I finally found where the broken neutral was

Your evap coils will be right above your furnace


Are any visible ac lines frosting up?

This is the ac coil.....most units are A coils

Frost like this is bad

6ohMax said:

Your evap coils will be right above your furnace


Are any visible ac lines frosting up?

This is the ac coil.....most units are A coils

Frost like this is bad

View attachment 3667731

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I couldn't find the ac coils in the attic, the seer rating is 16.5 with 18~24k btu https://www.trane.com/residential/e.../air-conditioners/xl16i-air-conditioners.html

It was short cycling earlier but now it's constantly running but after an hour it went 82>81 the copper pipe outside wasn't cold and the air blowing from the vent is 81 despite it feeling cooler, there were black smears near the copper pipe going into the inside unit does refrigerant leave black residue? I'm going to look up tutorials on changing refrigerant hopefully that would work

Just found a puddle leaking from underneath the indoor unit

If you don't know what you're doing, do not try and recharge the refrigerant as you will likely cause a catastrophic compressor failure if you overcharge. Run your hand along the lower side of all fittings feeling/looking for oil - if you find any you have most likely found your leak - if that's your problem (and it sounds like it could be).

IMHO you would be $$ ahead to call a HVAC tech.

GreatwhiteNorth said:

If you don't know what you're doing, do not try and recharge the refrigerant as you will likely cause a catastrophic compressor failure if you overcharge. Run your hand along the lower side of all fittings feeling/looking for oil - if you find any you have most likely found your leak - if that's your problem (and it sounds like it could be).

IMHO you would be $$ ahead to call a HVAC tech.

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Yeah I saw videos on how to vacuum pump out the condesate line that might save a hassle I'll have to make a diy vac>3/4" pvc attachment, if that doesn't work I'll finish up and call an hvac tech