Best Ac drain line treatment

[stoveliker]

So, having been gone for 4 weeks in July, I prepared my mini split drains by pouring a bottle of PF 2000 drain line cleaner (bought at the orange store) in the pan of each head, and adding tablets to the pan that were supposed to inhibit mold growth.

All was fine, I thought. It's been humid here and the thing has been running constantly (at 80 F when I was gone).

This morning (6 days after getting home, luckily), one was leaking. I e. Pan overflowing.
So I stopped that head.

I have before used my shop vac at the end of the drain line to suck out any debris in there. But I had later a disconnected drain line section in the channel that covers the lines on the side of the home. (Water leaking out of the line set channel)
I don't know for sure but given that the line goes from 3 ft below ground floor to the second story, it's tall and I suspect that sucking on it with the shop vac might have disconnected an already poor connection halfway up.

Still I'm going to do that again later today.

And pour another bottle of that cleaner in there.


What do you all do? Is there a better way? Better stuff?

 

[stoveliker]

I think @Brian26 and @fbelec may be professionally knowledgeable?

 

[mellow]

Well, I have made so much other stuff in my home smart, why not the AC drain

I haven't tried this yet as tablets have been working for me, but maybe yours needs more cleaner?

iFLO® Smart Automated AC Drain Line Cleaning System​

Amazon.com

 

[stoveliker]

Hm, I am unlikely to do the automatic one.
The tablets say how many per ton (head) and how often.
My pan is clean, it was the drain line that was clogged. Obviously a long line coming from the (ceiling of the) second floor down to ground level which is a few feet below the first floor.

What tablets (brand) do you use?

 

[mellow]

I will have to check with my AC guy, he leaves them up in the attic for me to put in the drain line in between calls, he says they are the professional only ones? They are white.

 

[stoveliker]

ok. I have green ones - Nu-Calgon Pan-treat 4296 "for professional use only" (...), but they are dark green.
1 tablet per ton per month.

 

[EbS-P]

Hm, I am unlikely to do the automatic one.
The tablets say how many per ton (head) and how often.
My pan is clean, it was the drain line that was clogged. Obviously a long line coming from the (ceiling of the) second floor down to ground level which is a few feet below the first floor.

What tablets (brand) do you use?

Is it 3/4” pvc drain line?

 

[stoveliker]

It's 3/4" indeed. Material I'm not so sure. Some "plastic".
Looks like this:

 

[blades]

Besides molds and slime scale builds up ,tablets are likely similar to CLR in a compressed powdered form.

 

[EbS-P]

I can see how that corrugated pipe would clog more when flow slows down.

Any way to replace it with hard PVC Once outside? Smooth walls give fewer places to grow gunk.

 

[stoveliker]

Yes, that's my gripe with this install.
If I get more leaks I may get on the ladder (maxing out 24 ft to get there) to cut off the drain lines outside and connect them to something else.
Hard PVC is unlikely given that the conduits (whatever the plastic line set covers on my siding are called) are pretty full already, and there are some 90 degs to go through, but something smooth indeed.

 

[blades]

you can get smooth wall hose in all kinds of diameters, 3/4" id is a standard. only reason for corrugated is it bends sharper with out kinking. All kinds of fittings and lines in the stuff they use for underground sprinkler systems

 

[Highbeam]

I don't even know how to throw tablets into the pan of my mini. It's been a few years now and I've never done that. Is it always necessary? Do you have to take off the whole outer plastic shell?

 

[stoveliker]

I only open the front, take the filters out. When you can touch the heat exchanger you can reach the pan; where water falls down from the fins, the pan is underneath.

 

[stoveliker]

I don't know if it's always necessary. If your pan remains clean, it might be good.
The coil does get dirty over time though. And that will get down. And that.l will "seed" mold in the drain line (which is for me corrugated...).

 

[gruesome]

Copper (or silver) should prevent any growth. If you can't replace the line with copper (our 3.5 ton A/C drain line is copper all the way), could you put a piece of copper in the drain pain? Maybe insulate it from touching any other metal, so it doesn't form a galvanic element. Supposedly this works for roofs (strip of copper along the top, to get biocidal copper ions trickling down with rain).

 

[stoveliker]

Interesting idea. Although the insulating it from touching other metals won't work given that (nondistilled) water is a conductor.

 

[stoveliker]

There has to be something wrong with the configuration of the pipe/hose.
It's been off for two days (65-70 f) but at 8.30 it was 80 F outside and humid (and windy; southern wind so from the ocean). I had the thing on dehumidification mode because it was humid there

At 4 pm I checked and found the pan almost overflowed again. And that after having vacuumed it while my wife poured a can of water in it. And then another can while I watched the outlet outside without the vacuum. Water came out normally.

I vacuumed it again with the shopvac.
Two hours later it again had water in the pan.

There can't have been a blocking as air clearly flowed thru after vacuuming, and the water too while vacuuming.

This suggests that somehow the draining quantity the hose can handle is lower than the head produces when it's humid and it's on dehumidification mode.

I may have to go up to the full extent of my 24' ladder to get the line set covers off and have a look .. maybe there's a kink someplace.

 

[gruesome]

Interesting idea. Although the insulating it from touching other metals won't work given that (nondistilled) water is a conductor.

Well, touching will make the corrosion work even faster.

Zinc and magnesium will work as sacrificial anodes. Zinc (plating) will protect steel. If you want to protect the plating itself, magnesium would work. For the sacrificial anodes you want the direct electrical contact. For the copper you do not. Anyways, might be worth a try.
Or you could make the whole drain pan out of copper.

The one thing I was worried about (and why I didn't spray the roof with copper sulfate solution): what will the runoff do to plants? But the condensate drain should be pretty minimal compared to rain, both in total quantity and copper ion concentration.

 

[stoveliker]

I know (have a master's in materials science) - I'm not taking a risk controlling corrosion in the pan. The welds and bends are a unknown.
And I don't want to put copper in the drain given it would decrease the available cross section for flow....

 

[gruesome]

Assuming the drain is accessible for at least a short distance, you could go plastic - copper - plastic for the drain line, i.e. insert a piece of copper tubing of the same diameter into the drain line.

 

[stoveliker]

Yes. It is accessible after going thru the wall (tho high up, not my best place to be).

But given what is coming out when vacuuming, I think it may be geometry/corrugation/kinks (?) that might be the culprit.

So I have to get up there ..

 

[fbelec]

sorry i'm late to the party. up here in massachusetts we get algae in the pipes. so it is not mold you will probably find it is green. i personally have my dehumidifier in the basement on my condensate line for the boiler. the stuff builds in the clear line that is 3/8 inch. doesn't take much but the same thing happens on ac evaporators with 3/4 of a inch pvc pipe. so what i do it's harsh but i got to do what i have to do. i use bleach. it kills the algae and leaves a film on the hose and it works for a while. you may not like the idea of bleach so put a bucket under the outside to catch it. but that works for me

 

[stoveliker]

Okay.
(Can Algae grow in zero light? My pool does stayed clean with the dark winter tarp, no chemicals except for what was left from last summer, during all of July...)

I'll open it up to see if all is mechanically okay (no kinks or obstructions in the geometry) before using bleach.

It hasn't clogged now since last time I wrote. But I haven't dated put it on dehumidifier mode. Just AC (so less water produced).

 

[begreen]

I don't even know how to throw tablets into the pan of my mini. It's been a few years now and I've never done that. Is it always necessary? Do you have to take off the whole outer plastic shell?

My guess is that units in our area are not running nearly as much in AC mode as back east. We've only had the AC on for a few days this summer. Normally the house cools down enough overnight with the windows open, to stay cool during the day. Even when we are running the AC it's with 50% or less humidity, not the sponge-wringing 80% back east.