Flushing Air Conditioner Condensate Line?
 

New in TV and going thru The Villages "Home Owner's Maintenance" recommendations list. One of the items is "Flush Condensation Line with warm water" every six months. I'm curious about techniques folks are using to keep that line draining properly.

In our new home the condensate line comes out of the AC, drops down a couple of feet into the slab, runs under (thru?) the slab for 25-30 feet then comes up in the side yard and ends in a gooseneck about 9" above ground. That's a lot longer run than I've ever seen and seems like it will be susceptible to pluggage. There's a cap on a tee in the pipe run near the AC unit that is removable for pouring or pushing something into that line. It seems to me that just pouring a couple of gallons of warm water into the pipe would not be enough to keep such a long run flushed out. Can you use a hose to feed a flow into the line? - thinking that pressurizing the line might push water into the AC unit and flood there. Anyone use a chemical to add to the poured flush water to help stop slime growth without damaging the pipe? Am I overthinking all this? (probably - that's a common problem for me...).

Thanks for any thoughts.

I modified mine With cut off valve to prevent back flow and use water pressure to flush it out takes about 5 mins. Some use compressed air/ shop vac. This has been discussed several times. Do search or look in “ do it yourself”.

I sent you a PM Len

I just use the "blower" side of my shopvac with the small round attachment then throw in a cup of bleach. LOT'S of crud comes out the other side. :D

I don't worry about it, I have the A/C serviced every 6 months and they flush the line as part of the service. In our previous home we had to replace the heat pump and I had the new one serviced twice a year. When we sold the house the unit was 17 years old and still functioning properly. A heat pump is just like your car, it needs regularly scheduled maintenance.

Our AC stopped working after the condensate safety valve kicked in which disables the AC...tstat in house display went blank. Light compressed air and then hot water restored all.

The situation you describe. I had a new AC installed and neglected to clean the line. The condensation line got more and more clogged. I would at first get intermittent stoppages as the condensate level reached the safety cutoff switch. But it would come back as the condensate gradually seeped out. As the season progressed it became more of a problem to the point where I discovered the blockage. I tried the outlet air from a wetvac with no success. Then took a hose with no metal fitting and shoved it into the drain line. Taped it in place to seal the connection. Turned on the hose and it cleared it immediately. Since then, I use that method as a preventative. I think better result than hoping vinegar/bleach will work. Takes a couple of minutes to set up and you know immediately that it worked.

Twice a year pour a couple ounces Dawn liquid soap in the line and chase it with very warm water. I have a 25 foot run from the air handler to the end of the condensate line. Never have had a problem in 15 years.
I got this tip from an AC service professional.

Don’t overthink it !
 

It cost me $140.00 to learn to suck the dirty water clogged with algae with a shop vac. Refill the line with fresh water and add a couple of ounces of vinegar every couple of months. That’s it.

Half a cup of water mixed with half cup white vinegar once a month has kept ours clean for 16 years...

I was told by a/c man a couple of years to pour 2 gallons warm water down it every month instead of waiting for 6 month check ups. My unit is 8 years old. Takes 5 minutes once a month.

I was told to pour a gallon of hot water down the line every month. I have been doing that for the four years we have been here. During the annual service the tech uses a hose and with the pressure of the water from the hose also cleans it.

Thanks!
 

Thanks everyone for the good feedback! All of these approaches sound good - I’ll just pick one and be consistent about using it. From looking at the variety of options it seems like the consistency part is the key.

I used antibacterial soap in a gallon of warm water once a month poured into the drain. However, due to the length of the drain, I was experiencing blockage and backup to such an extent that the boxed area where the A/C sits became water logged. I had the drain reconfigured for a shorter run and the boxed area rebuilt. Since I had installed a new A/C unit in 2019, my contractor covered the cost of repairs. I will still use the soapy water in the shorter run.

We have our unit checked 2x a year....once the drain pipe backed up

I now pour a couple of quarts of boiling water down the pipe every 3 months...I was specifically told to not use bleach as that will cause issues