How they work
Caustic cleaners heat up and dissolve hair and grease. Acid cleaners are stronger still. In a partly blocked drain they can open a channel. In a fully blocked drain they pool in the trap, with nowhere to go.
The downsides
- They can damage old metal pipes and rubber seals
- They can splash back into eyes and onto skin
- They make any later mechanical clearing more hazardous
- They rarely remove the clog completely
Better options
- Pull and clean the pop-up stopper in a bathroom basin.
- Use a cup plunger, with the overflow covered.
- Try a plastic drain-cleaning strip for hair clogs.
- Remove and clean the P-trap under the sink.
- Use an enzyme cleaner for maintenance, not emergencies.
What a plumber actually uses
On a hair clog in a bathroom sink, we remove the pop-up assembly and pull the hair out with a hooked tool. In a tub, we take off the overflow plate and run a small drum auger. For kitchen grease, a cable with a cutting head followed by hot water usually works. None of these leave residue in your pipes.
When to call
If those steps fail, or several fixtures are slow, call. See drain cleaning, bathroom drain unclogging and grease and kitchen drains.
Keep-handy checklist
- Close the inside valve for the hose bib before the first frost
- Keep fat in a tin, not down the kitchen sink
- Check the toilet for a silent leak with a few drops of food colouring
- Note where the main cleanout cap is and keep boxes off it
Your questions, answered plainly
Are enzyme cleaners safe?
Gentler, yes, and handy for routine upkeep, but slow and not suited to a complete blockage.