Flushing AC Unit
 

After pouring white vinegar down the line, how many of you pour hot water down right after the vinegar?

If you do, how long do you wait for the hot water?

thank you!

I just use hot water every month or so.

Hot water is sufficient

Our AC tech told us not to use vinegar. Just hot water with a few drops of dawn dishwasher detergent.

If you really want to flush out the condensate line, buy one of these. It does a better job than hot water or vinegar.

Amazon.com

We have a service contract with Munn's, they come every six month to inspect and service our unit as well as the thermostat and air handler. They told us just to use hot water and they do a more complete clean-out when they do their service. Well worth the minimal cost to have peace of mind.

Ours told us the same thing. Although I can’t find anything that says vinegar will damage pvc. I just flush with hot water every month now.

Shop vac on the outside pvc drain tube ….. vinegar/ bleach is fine ..I was an AC guy, now I’m old, grey, and don’t feeling like doing anything

I use a very small bottle of bleach and chase it with a gallon of HOT water every six months. For me it works great. I can use a flashlight to look into the drain and it's pretty clean and clear. A little staining on the sides of the pipe but that's all..

I fill a pail with about a gallon or so of hot water and a dash of soap. use a funnel and pour it down the drain. Then I rinse the soap residue out of the pail and fill it with just hot water and pour that down the drain. I do this a few times a year.

I think the risk is damage if vinegar/bleach gets into metal parts of the HVAC drain pan.

Same with us.

We have used both but not at the same time.

- The idea behind vinegar is to raise the acidity and kill any slime growing in the lines. The argument against vinegar is that it is harmful to aluminum and as it evaporates in the line the vapor could come back into your air handler. It seems like that would be a very tiny risk at best, but that's the argument. Pouring water after the vinegar would dilute the acidity and the effectiveness.

- A gallon of hot water works both to kill anything with the heat and to flush it out with the volume. This seems to make sense, is pretty simple, and costs less than vinegar (save a few pennies)

- A hose attachment to force water through the line would certainly provide the volume and the pressure could be enough to clear a buildup. I would be concerned about creating a leak in a place I cannot reach to fix but PVC is strong enough so that really shouldn't happen. Munn's used this technique on my system during their maintenance visit.

- A shop vac pulling from the outside to clear a blocked line seems like the safest approach to clearing a clogged line. However, it would be best to use one of the three above to prevent the line from becoming clogged in the first place.

why flush the vinegar out? it will in no way harm the drain and the longer it stays in the pipe, the more work it will do.

Where is the drain located that you pour the hot water in?