How old is you’re house? Unless the float in the catch tray inside the unit I see none on my trane xr12.

I flush mine monthly during the hot summer months. Also, after flushing, I put my shop vac on the pipe outside and suck what is remaining out.

Re: Ac drain line service
 

This issue has been often debated. I've heard BLEACH. I've heard VINEGAR. I've heard you should use nothing but WATER as bleach or vinegar damages both the AC coils and the dranin pipe.

All home may not be set up the same. Our home is five years old and we have an original extension on the end of the drain line where it connects to the equipment in the garage. Easy and quick. Once a month I pull off the plastic cap on the end of the pipe insert a funnel and pour warm/hot water down the pipe. We catch the flow through water to see how dirty the tube was. The first gallon is obviously dirty-brownish yellow with some small chunks of groth in it. Second gallon is clean-clear water not chunks-DONE. Once a year we have a periodic tune up. The service guy hooks up a wet dry vacuum to the line and pulls the water out.

They send out ONE person. According to a radio show I listen to, it cannot be properly done that way. Once he pulls the watr out all he is doing is sucking air through the line. The right way to do it is to add watter while the vacuum is runngin. So far no problems.

ASIDE-everything has a normal service life. On your AC the capacitor lasts about 4 years. The compressor about 14 years. All of your ACs are mareked with the SEER# a mathematical calculation of efficientcy. Ours is 15. I expect there are still some homes with 7 in the villages. Today 18 is readily available. The numbers and what they mean few understand-including me. I've been told by a claimed expert if I changed from 15 to18-roughly 30% my cooling bill would go down like 10%-HUH?

I had it happen once, it was in 1992 and that's how I found out about maintenance. My A/C was in the laundry room in the basement and on the other side was a family room with carpeting. One day I walked into the FR and the carpet was wet. Traced the water back to the A/C and called a repairment. He told me then about bleach, which I used for many years until switching to vinegar last year. Occasionally I bring the water hose into the garage and flush it out with the fast sprayer. Our A/C unit is not enclosed in the garage and it's very easy to see the pipe.

Federal law requires a min of SEER of 13 and has since 2006, the standard before that was SEER 10, it was adopted in 1992. There are no SEER 8s here. They died long ago. SEER is how many BTUs per watt.

Your savings would be (in your example) 15/18 -100 HVAC savings percentage X the percentage of electricity for HVAC. Let's use my year to date useage of electricity for HVAC (since you probably don't know yours) 53.5%. Thus 16.6666 % HVAC savings X .535 or 8.916% savings on your electric bill.

I unplugged mine by using my shop wet/dry vac on the outside outlet and sucked all sorts of bad stuff out.

Just had our unit replaced and the installer said not to use bleach as just the fumes alone from it would affect the aluminum A coil which is in the new system. (No longer copper) So you need to play it safe if you are not sure which type of A coil you have. Vinager and warm water best bet. Shop vac does ot hurt. But I like the OP’s water solution with the hose as long as it does not pop out of pipe.

7 years old. Carrier unit. Float in a tee in the condensation line (where the water flow turns 90* down) about 8" from the air handler unit.

My unit 12 years old don’t have the shutoff float.

Air Condensate drain
 

OK When the cold coils in the Air Unit come in contact with our high humidity air, the water drops out, off the coils and goes into a pan and then to a small white PVC line to drain outside. The water goes to your plants etc.
So, you can use a wet or dry vacuum or an air line if you have a compressor, it will blow out the line. It sometimes gets plugged because it is gravitating to the outside, it can get dead bugs in it, you can put a small piece of mesh at the end. You will find it in a planter or planted area, white PVC about 3/4 diameter.
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