Why isn't drain cleaner unclogging my drain?

Poison Control describes drain cleaners as products with enzymes and other strong chemicals that "break down oily and greasy residues found in sink and shower drains." That tells you what they are aimed at: grease, soap film and the sticky layer that lines a pipe. Some of them work partly through heat, and Poison Control notes that the heat "helps melt grease and other oily drain-blocking substances."

Other kinds of blockage are not made of that material. These are the usual reasons a cleaner fails:

• A solid object. A toy, a jar lid, a bar of soap or a wad of paper towel is not grease. Nothing in the bottle breaks it down.
• A thick mat of hair. Hair and soap scum knit together into a plug. AAA quotes a plumber who says that when hair and soap scum are the cause, "a plunger may be all you need."
• A clog the product cannot reach. If the blockage sits past the trap, in a branch line or in the main line, the cleaner may drain past nothing or sit in a pipe that is already full.
• Roots. Phoenix Water Services says roots probe a sewer line "seeking any opening," and once inside, "the roots form a ball and block the line." A cleaner poured in a sink does not reach a root ball in the yard.
• Grease that has hardened farther down. Phoenix says grease "eventually cools down, congeals, builds up, and hardens," even when it was followed by hot water. A cleaner poured into a sink can soften the first few inches while the hard plug sits well past it.

Whether the cleaner fits the clog is our read of what these sources describe. What they show plainly is that grease is the target and that roots and grease are the two main causes of sewer backups in Phoenix.

### How long should I wait before I call it a failure?

Follow the label. Every product lists its own wait time and its own limits. If the water has not moved by the time the label says it should, treat the product as done. More chemical in a full pipe only means more liquid you have to work around.

Stop adding product and move to a mechanical fix. If the drain is now worse than before, read why the drain is worse after using Drano as well. Be careful here, because the sink now holds a chemical solution.

1. 1Protect yourself first. Poison Control's prevention tips are to wear goggles and rubber gloves, pour drain cleaner close to the drain to avoid splashing, and keep the containers closed and away from children. The same goes for anything you touch that has been in contact with it.
2. 2Do not pour boiling water in. AAA warns that hot water "might melt some of the gunk and push it farther down the pipe, where it hardens into a second clog," and can cause pipes to "expand and contract, leading to leaks."
3. 3Expect splashback. Poison Control says injury can occur when a drain cleaner "splashes back from the drain area," which can happen "if too much product is poured into a completely blocked drain." For that reason, we would not plunge hard or open the trap while the cleaner is still sitting in a full pipe.
4. 4Go for the trap. AAA lists the P-trap as a standard step. Place a bucket under it, unfasten it, and clear it by hand. Wear gloves and eye protection, since the liquid in there may still be strong.
5. 5Try a plunger or a snake. Once the water level is low, AAA notes that a plunger "uses suction to break up the clog, not ram it through the pipe." A drain snake can hook hair and reach beyond the trap.

Our safe alternatives to chemical drain cleaners page walks through each of these, and what an enzyme cleaner can and cannot do explains the milder kind.

### Will baking soda and vinegar or an enzyme cleaner do better?

Probably not on a hard blockage. Poison Control says baking soda and vinegar produce carbon dioxide, but because drains are not airtight the gas "can escape from through drain cover," so it "generally does not build up enough pressure to release clogged drain contents." It adds that the mix "is unlikely to be strong enough to melt away tough drain clogs due to oil and grease." Poison Control describes enzymatic cleaners as containing "bacteria and enzymes that dissolve clogs." Our baking soda and vinegar and enzyme cleaner pages set out what to expect from each.

### What if I already used two different products?

Stop and read the labels on both. Poison Control's advice is to treat these as potentially dangerous when used incorrectly, and MedlinePlus states plainly that drain cleaners "contain very dangerous chemicals that can be harmful to your health if you swallow them, breathe them in (inhale), or if they come in contact with your skin and eyes." Open a window, keep children and pets out of the room, and do not add anything else. If anyone is exposed, Poison Control's number is 1-800-222-1222.

If more than one fixture is slow, the blockage is probably past the branch that serves that sink. Watch for signs like water rising in a tub when the washing machine drains, or a toilet that gurgles when you run the sink. Our main line vs branch clog page shows how to tell them apart.

A clog that keeps coming back after you clear it is also a sign that something deeper is wrong. See why the same drain keeps clogging. Phoenix Water Services adds that the owner is responsible for the sewer line from the house to the city main, and that if you notice a reduction in flow, "have a plumber check the line and clear the blockage if necessary."

### What does a plumber do that a cleaner cannot?

Oatey says a drain-cleaning company can scope the line, which means sending a remote camera down it to see what is there, and that most of the time grease blockages "have to be jetted out." A liquid poured in a sink cannot do either. You do not need to have tried everything else first. If a snake will not clear it, or you have already used a chemical product, call.

Drain cleaner is a tool for grease and soap film. If the drain is still blocked after the label's wait time, stop adding product, do not use boiling water, and clear the trap or use a plunger with care. If several drains are slow, or the water is backing up, the blockage is deeper and needs a plumber.

HQ Plumbing & Air is licensed and insured, gives free estimates and upfront pricing, and answers 24/7. When you call, tell us which product you used and how much, so we can protect ourselves and your pipes before we open anything up.