House AC suddenly not working!

[DannyW]

Does the condensate drain have a float switch that shuts the unit off if the condensate is not draining?

I found out the hard way this is the first thing to check. Since my air handling unit is in my garage the float switch is dangling free so it cannot shut off my AC.

Pour some vinegar every now & then in your drain line to keep it clear of algae which can cause condensate to back up.

I agree with your maintenance suggestion, and even thought of this being a possible cause of the OP's problem. But I dismissed this as a possible cause when the OP said the outside fan was still running and blowing cool air. When the condensation pump quits or is clogged, it shuts off power to the outside unit. Or at least it does with mine.

I have a problem with my condensation drainage lines on the upstairs system. They clog up sometimes and I have to vacuum the water out of the drain line. While I am vacuuming out the water from the outside drain pipe, it reaches a point where the float resets and the outside unit kicks back on. (I know because I'm standing next to it.)

 

[Gator89]

I agree with your maintenance suggestion, and even thought of this being a possible cause of the OP's problem. But I dismissed this as a possible cause when the OP said the outside fan was running. When the condensation pump quits or is clogged, it shuts off power to the outside unit. Or at least it does with mine.

Correct, everything shuts off on mine too.

I admit, I only skimmed the OP.

 

[oldfella1962]

Turned out to be no refrigerant. The outside unit (condenser) was working just like it was supposed to, compressor running & whatnot. But there was no refrigerant.
The system is 19 years old so I would say it's had a good run. Somebody in this thread
mentioned 6K to get a similar replacement set (heater/evaporator and outside condenser) and sure enough with labor it will run 7K.

 

[Doboy Dawg]

Turned out to be no refrigerant. The outside unit (condenser) was working just like it was supposed to, compressor running & whatnot. But there was no refrigerant.
The system is 19 years old so I would say it's had a good run. Somebody in this thread
mentioned 6K to get a similar replacement set (heater/evaporator and outside condenser) and sure enough with labor it will run 7K.

At that price you should get new line sets, for the liquid line and the suction line. Make sure they replace them and not reuse the old refrigerant lines.

Plus none of the companies will tell you but the R410A units are 10% less efficient at removing humidity, cooling, than the R22 units.

My new 410 unit doesn’t cool as good as my R22 unit did. I found that was also in my HVACR course book when I took 2 years of HVAC school at our technical college.

 

[oldfella1962]

At that price you should get new line sets, for the liquid line and the suction line. Make sure they replace them and not reuse the old refrigerant lines.

Plus none of the companies will tell you but the R410A units are 10% less efficient at removing humidity, cooling, than the R22 units.

My new 410 unit doesn’t cool as good as my R22 unit did. I found that was also in my HVACR course book when I took 2 years of HVAC school at our technical college.

yes the tech said that the price includes new line sets because they are obviously old and compromised. Didn't know about the new type of refrigerant being less efficient though! If they wanted me to spend more money and go to the nest larger sized system I might have taken that bait! As it is though I'm getting pretty much the type of system I already have, just new. IMHO the most important thing is the company has been in business for over 25 years so they aren't fly-by-night. So far at least they communicate well and have their act together, which is getting more and more rare these days.

 

[GTMODawg]

According to the industry R410A is more efficient than R22 but most end users ain't convinced. Supposedly the newer stuff transfers heat more efficiently but most end users say their homes and offices aren't as comfortable as they were for the same energy costs. All studies indicate the new stuff is more efficient but most of those were paid for by the industry or environmental groups so the data is likely skewed. The industry could care less about energy costs but selling new units is something they truly believe in. There is also some anecdotal evidence that components degrade somewhat faster with the new stuff. When an industry wide shift to new and improved happens it is usually the bottom line of the industry which is new and improved while the wallet of the end user is the same old wallet which is not improved so much.....

 

[bfriendly]

yes the tech said that the price includes new line sets because they are obviously old and compromised. Didn't know about the new type of refrigerant being less efficient though! If they wanted me to spend more money and go to the nest larger sized system I might have taken that bait! As it is though I'm getting pretty much the type of system I already have, just new. IMHO the most important thing is the company has been in business for over 25 years so they aren't fly-by-night. So far at least they communicate well and have their act together, which is getting more and more rare these days.

When it gets upper 90’s outside you gonna be a happy man old fella! Might should ask if they’ll give you a box of filters too. Get good ones and replace as needed…..they ain’t cheap!!! Stay cool!

 

[ClemsonRangers]

be careful going bigger, it will cool faster, but not remove the moisture and could cause mold