So, I lost my HVAC guys and havnt had a chance to find new ones. Therefore, I Havnt had service in a year. The AC shut off on me and realizing the display was the only thing without power I checked the drain line and safety switch. The drain line is nearly completely full of yellow gelatinous goo. I was able to clear it enough and the tee to get the AC back on for now. I can clear the line in the daytime.

But for the HVAC pros, do you guys have an algaecide tablet that gets put into the air handler when y'all do maintenance or do you just run some bleach and a snake in the trap and hood for the best?

Inquiring minds want to know.

Hey ac twin. Mine shut off on me tonight too. Small green ac chlorine tablets once a month or a little bleach down the line.


Gotta get me an emergency guy out tomorrow. Mines 10+ and I had Al intentions of getting it replaced this past winter.

You're right!

Does your AC drain with anything else like a sink?

My AC connects drains with my master bath sinks and sinks start getting backed up 1-2 times a year. Finally had a plumber advise to use Green Gobbler Enzyme drain cleaner once every month or two for prevention and has been working well since.

87IE said:

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Not a HVAC pro...............

My AC guy told me to use vinegar instead of bleach.

I've seen him use compressed air to clear it out but I've used that or a 25 foot snake. During the cooler months I try to remember to pour some down the drain line when I change my filter.

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I've talked to a few AC guys and they said bleach, at least in Houston, is fine. The air is so humid that no residue will be left long enough to cause any damage to the PVC.

I typically pour bleach down twice a year. Turn the AC up a few degrees so it won't run. Pour down bleach, wait about 10/15 minutes, then turn the AC back down. If I happen to be in the attic between those times I'll do it then also. Since doing this, never had an issue with my sink it drains into backing up.

I try to remember to do the bleach a couple of times during the summer and then winter also before spring hits. Those other remedies are interesting, both my drains go into sinks so I don't get to see them. My old house drained outside so it was easier to monitor.

Also slightly off topic, if you don't have a dry/wet switch and the units are in your attic, put one in to save the potential overflow issue.

Haha…yeah, I was in my attic at 2am…cause I'm not going to deal with it tomorrow. Anyway, bleach is fine for clearing the pvc drain line, pool equipment uses PVC. bleach is ok. Bleach is NOT ok for the pan inside the where the coil is. It will rot the pan. So, that's why I was asking is anyone has used pan tabs that are designed for that. They use enzymes like Brawndo for HVAC….

Jason_InfinityRoofer said:

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Haha…yeah, I was in my attic at 2am…cause I'm not going to deal with it tomorrow. Anyway, bleach is fine for clearing the pvc drain line, pool equipment uses PVC. bleach is ok. Bleach is NOT ok for the pan inside the where the coil is. It will rot the pan. So, that's why I was asking is anyone has used pan tabs that are designed for that. They use enzymes like Brawndo for HVAC….

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Unless I'm mistaken, but if your pan is filling with water wouldn't that be indicative of another problem, i.e. your main drain line being clogged? I don't use anything in my pan because it never has water in it.....I pour the bleach directly in the vent for the drain, which prevents a clog and water ever getting into the pan.

htxag09 said:

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Jason_InfinityRoofer said:

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Haha…yeah, I was in my attic at 2am…cause I'm not going to deal with it tomorrow. Anyway, bleach is fine for clearing the pvc drain line, pool equipment uses PVC. bleach is ok. Bleach is NOT ok for the pan inside the where the coil is. It will rot the pan. So, that's why I was asking is anyone has used pan tabs that are designed for that. They use enzymes like Brawndo for HVAC….

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Unless I'm mistaken, but if your pan is filling with water wouldn't that be indicative of another problem, i.e. your main drain line being clogged? I don't use anything in my pan because it never has water in it.....I pour the bleach directly in the vent for the drain, which prevents a clog and water ever getting into the pan.

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Main pan inside the unit, not the overflow pan.

TexAg1987 said:

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htxag09 said:

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Jason_InfinityRoofer said:

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Haha…yeah, I was in my attic at 2am…cause I'm not going to deal with it tomorrow. Anyway, bleach is fine for clearing the pvc drain line, pool equipment uses PVC. bleach is ok. Bleach is NOT ok for the pan inside the where the coil is. It will rot the pan. So, that's why I was asking is anyone has used pan tabs that are designed for that. They use enzymes like Brawndo for HVAC….

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Unless I'm mistaken, but if your pan is filling with water wouldn't that be indicative of another problem, i.e. your main drain line being clogged? I don't use anything in my pan because it never has water in it.....I pour the bleach directly in the vent for the drain, which prevents a clog and water ever getting into the pan.

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Main pan inside the unit, not the overflow pan.

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Gotcha.

htxag09 said:

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TexAg1987 said:

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htxag09 said:

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Jason_InfinityRoofer said:

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Haha…yeah, I was in my attic at 2am…cause I'm not going to deal with it tomorrow. Anyway, bleach is fine for clearing the pvc drain line, pool equipment uses PVC. bleach is ok. Bleach is NOT ok for the pan inside the where the coil is. It will rot the pan. So, that's why I was asking is anyone has used pan tabs that are designed for that. They use enzymes like Brawndo for HVAC….

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Unless I'm mistaken, but if your pan is filling with water wouldn't that be indicative of another problem, i.e. your main drain line being clogged? I don't use anything in my pan because it never has water in it.....I pour the bleach directly in the vent for the drain, which prevents a clog and water ever getting into the pan.

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Main pan inside the unit, not the overflow pan.

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Gotcha.

My point still stands, though, no? If you're properly treating your drain line then your main pan shouldn't fill with water, no need to put treatment in the pan? I guess unless you just don't want to go into the attic twice a year to treat the drain line.

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The condensation forms on the coils, drips into the pan where it is carried to the drain line.

I think the point is to put the tabs in the pan so the water slowly dissolves the tabs and carries it to the drain line. If you put the tabs in the line, they get carried away whole immediately.
In my experience there is buildup in the pan too, so in order to treat everything, start in the pan and let it wash down into the drain.

I edited my reply because I don't fully understand the problem, I've never done anything to treat inside my pan.

I'll let the various board's AC techs weigh in.

Quote:

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The air is so humid that no residue will be left long enough to cause any damage to the PVC.

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It's not damage to PVC plumbing, it's corrosion of your metal coil that makes bleach a bad choice.
https://hvac-talk.com/vbb/threads/913532-Don-t-use-Bleach

Pretty sure this guy lives within 10 miles of you

Give him a call. Great guy. No nonsense.

Hector Hurtado.

(Medina co area) nine 31. Four 369.

The best prevention is slope. 1/8" per 1'.

Nucalgon makes some pan treat tabs that probably work? We've used them for years but never really vetted that they work lol. But seriously, the best thing is to keep the water flowing. If you've got an air handler (heat pump) the drain is likely on the negative side of the blower so you'll need a trap in the system and then a vent after the trap. A lot of times we install a blow line on the lead edge of the trap but it should be capped with a removable cap.
For clearing a clogged drain I recommend 100psi of air followed by three gallons of hot hot water. Bleach or vinegar are options to put in the system as well. I don't worry about bleach affecting the pan as you should be introducing it to the system after the pan and even if you didn't it won't be in the pan for long. Another thing to note is that in older homes the AC just dumped into a plumbers stack in the attic and when feasible I seal that fitting with a reduced and leave a vent on it that's higher than the evap coil so when the plumbers pipe stops up your AC doesn't flood your house and will back up into the unit and hopefully a float switch will kill it.
Glad you had the ability to get it going at 2am. Happy wife happy life right?

Thanks for the suggestions and referrals above!

All your stuff checks out on my unit. The issue, was this goopy yellow algae that had created enough of a blockage in the part coming out of the air handler such that it filled the secondary with water and tripped the safety switch. My house is a late 1800s build retrofitted with central AC. The main drain line runs outside and the secondary doesn't exist. Yes I have a drip pan under the air handler which is suspended. However the secondary line has a special trip switch which works quite well.

Anyway, I found a snakey brush, a gallon of hot bleach water and cleaned the trap. She's flowing fine now. I'm going to clean the coil with a foaming cleaner and drop some tabs in the pan and see if that helps.

My annuals maintenance usually handles and blows those lines out but he bailed on me so I'm doing it until the fall.

I already bought and replaced the UV light and I'm pretty good with my origami style box filter. I might as well buy some gauges (kidding, I'm not fooling with that). I have a new AC company for the fall so good there.

Ahem, any insight on Armstrong brand? Haven't heard much

Sorry, saw your post and got distracted. If you believe consumer reports they are the top name in hvac…... I'm not a fan. It's a Lennox product. Lennox is garbage. With enough money spent on marketing and review farming anything can become "the best". Lennox hasn't recovered from their black eye over leaking coils from 10 years ago or less. So to keep the factory running they are quietly (not really) building up their lesser known brands. In my opinion the top manufacturers of HVAC equipment today are Carrier and Rheem and their respective brands. At the end of the day though, how it's installed and who installed it are the most important factors.

Every time I do a make ready or on any houses I work that have a drain issue I always used compressed air to clear both drains and then once verified clear I pour a few ounces a bleach at the clean out as a preventative. Also every march I always add bleach as a preventative to the clean outs. I also like to install water alarms in the overflow pans to alert homeowners/tenants that there is a problem before the pan backs up and floods the ceiling drywall etc.

Thank you for the insight, no need to apologize, just saw the username and thought I'd try to fish for a little info.


Have a 10-15 year old Tempstar that other than a few capacitors, hasn't given me any issues. Cools the house moderately well for being built in the 80s.

My office tends to run hotter here recently since we lost all tree coverage in a tornado a few years back, so we were looking into getting an extra vent and new ducts all throughout the house and a new unit while we were at it.

First bid we got was for an Armstrong unit, and I'd never heard of it, other than a quick google search. I, like yourself have zero faith in online reviews for the exact reason you mentioned.

87IE said:

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Not a HVAC pro...............

My AC guy told me to use vinegar instead of bleach.

I've seen him use compressed air to clear it out but I've used that or a 25 foot snake. During the cooler months I try to remember to pour some down the drain line when I change my filter.

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Yeah, bleach is tough on pvc and glue. Use vinegar. Also check the drain tee that is likely connected under a sink because they do get gunked up.

I do vinegar and hot water every 3 months when I change filters.

I use bleach. But like a lot of folks....I tend to forget. Both lines clogged up on both of my units on father's day.

NO PROBLEM.

This tool has paid for itself probably 10x over....

https://www.homedepot.com/p/Milwaukee-M12-12-Volt-Lithium-Ion-Cordless-Drain-Cleaning-Airsnake-Air-Gun-Kit-with-1-2-0Ah-Battery-Toilet-Attachments-2572B-21/303169749

I got one of these: https://www.amazon.com/Leak-Saver-Condensate-Non-Contaminating-Cartridges/dp/B07THM2122

Do you guys not own air compressors?

So I have a slightly different version of this problem. My unit is in a small closet in the garage instead of the attic. The condensation drain line go into steel pipe thats open ended and flush with the floor of the garage, right next to the unit, not sure where that ultimately drains to. In the afternoon/evening the steel line backs up and water overflows onto the garage floor. I'm assuming dirt/dust has probably clogged up that line somewhere? Safe to try drano to open up the restriction so the drain line doesn't back up?

A lot of time this will be shared with another drain line or is it clogging at the trap. I would run an auger through it to open it up. You can also try a drain bladder like this


https://www.lowes.com/pd/Drain-King-Rubber-Bladder/1000351531



This is a great product to use monthly on drains to prevent and clean away build up


https://www.lowes.com/pd/Zep-Drain-Defense-Pipe-Build-up-Remover-64-fl-oz-Drain-Cleaner/3745757

Thanks!

Locally we can get Slime Out tabs & Johnson Supply near old Travis Golf course lake.
Then switched to ProTreat
Now thinking these better http://rb.gy/zl42j

Might be a dumb question, but wouldn't a larger size line help prevent this problem, or would it just happen anyway? I always wondered why the line couldn't be a little larger.

I don't want to drag it upstairs, and then up more stairs to the attic. The HVAC Leakshot fits in my pocket

We use Nu-Line drain cleaner. Pour it down every 3 months or so. Big problem for us the the main drain line goes to the bathroom sink and connects just above the P trap. We have two units that go to two separate bathroom sinks.

https://www.amazon.com/Nu-Line%C2%AE-Drain-Cleaner-ounce-Sold/dp/B00WUOLD96

Dumb question, but for the AC drain line, do you need to pour hot water after you pour the green gobbler?
I just poured one of those 16 ounce bottles down my drain line per my AC company. My system is only 3 years old.
They were here in June and cleaned it…told me to do vinegar or green gobbler once a month…of course I didn't do it. I went up in the attic to change my AC filter and found water in the pan.

Got the water out using a turkey baster and put in a Home Depot bucket. Took me about 20 minutes to suck up 2 gallons . I could have used a shop vac but didn't want to mess with. Turns out I the attic heat makes your heart rate go up…my Apple Watch started alerting lol

So the AC is off now, the instructions on the bottle just said "pour it down" so not sure if I need to wait or what.