[Mike Shebel]

Make an adapter to attach to your garden hose. The adapter is a piece of flexible tubing that will fit inside the PVC drain. The flexible tubing should be 8 to 12 inches long, that way, the water you put in the PVC will be well beyond the tee connection going to the air handler.

[Scorpyo]

Originally Posted by mtdjed

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.

Thanks. I photocopied your response for future use. This whole thread has been very helpful. I have a home in GA and a Villa in TV. In GA I change my condensate pump every other year -$50. I was wondering where the pump was located in my Villa. Now I know. They simply forgot to install them in TV. Lol

[ranger712222]

When Munn's service came over they flushed the line with the garden hose. They did that at the tee where the cap is located.

[Villagesgal]

I have used a cup of plain white vinegar followed by 2 cups of warm water once a month for the last 19 years and no problems at all, don't use bleach, left over fumes can harm metal parts in the air handler, use vinegar.

[worahm]

Most AC companies use a small vacuum to vacuum the condensate line for 15 or 20 minutes minutes. Then pour a gal of warm water into the line at the air handler and vacuum again. The line exit is usually located at the outside condensing unit.
NEVER use Bleach. The chlorine fumes will corrode the evaporator coil in the air handler.

[cassjax2]

Just had this problem in June with our A/C. Our A/C guy said to put 2 cups of white vinegar down the line (A/C NOT running!) every 2 months and the line will stay clean.

[TandHSTAR@AOL.com]

I have my unit serviced twice a year. They flush it out. All part of the maintenance. Never had a problem. .

[17362]

Originally Posted by Number 10 GI

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.

We do that too. Ours is 17 years old. Plus we run plain hot water through once a month. Yes, crud still comes out. It’s still working great and no corrosion in the unit from chemicals being used.

[Rebel Pirate]

Originally Posted by davem4616

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

This was my thinking originally...if warm water is good, then boiling water will be better. However, an AC repairman cautioned me on that. He said the glue on PVC pipes is meant to distribute domestic hot water which may be about 140-150 degrees, depending on how high you set your water heater. But the glue is not rated for 200 degrees and too many cycles of 200 degree water will cause the glue to fail. Then, you've got a leaking connection beneath your slab.

[jjombrello]

My instruction book says to mix 1/2 cup of bleach with 1 cup of water and pour it into the drain. Really simple and works great. Been doing it for 21 years, about every three months. I have twice a year service and the drain gets cleaned when that is done.

[bilcon]

My service company, Sunshine told me to pour hot water with some Vinegar down the line once a month. No problems in 11 years.

[jrenschen]

just use vinegar. Gets rid of the mold!!!

[Kilmacowen]

Originally Posted by Mike Shebel

Make an adapter to attach to your garden hose. The adapter is a piece of flexible tubing that will fit inside the PVC drain. The flexible tubing should be 8 to 12 inches long, that way, the water you put in the PVC will be well beyond the tee connection going to the air handler.

Yes, an old wash machine hose cut about 12" attached to your garden hose to get by the tee so the water doesn't back into the air handler. I use simple green, then flush.

[joeharing]

warm water and white vinegar 50/50

[Ladygolfer93]

Originally Posted by mrf6969

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.

Pretty similar from my AC company. For some reason (?) my Trane had no safety cut off (???) so had a puddle of water on the furnace pedestal before I realized what was happening. I used the tablets you just drop into the line for a long time after that, but AC person told me that a cup of vinegar would do the same thing much cheaper as long as I set a day *first day of the month, and do it every month without fail. For over a year had worked just as well as the costlier tablets ! Bought the super size Costco 1.50 gallon size to put out in garage to remind me !