Why we ask you not to use chemical drain cleaners
Updated Sep 6, 2026
They can cause more harm than good
Chemical drain cleaners promise a fast fix, but they carry real risks, especially in older Westside homes with aging pipe. We ask customers not to use them, and here is why.
Pipe damage
Many chemical drain cleaners work by generating heat or a strong chemical reaction to break down clogs. In older metal pipes, this heat and chemical exposure can accelerate corrosion. In PVC pipe, repeated or heavy use can soften or warp fittings over time. Either way, the chemical is not selective about damaging the clog only; it affects the pipe itself.
Safety risk for whoever works on it next
If a chemical drain cleaner has been used and the clog is not fully cleared, residual chemical can remain in standing water in the pipe or fixture. When our technician then needs to snake the line or remove a trap, that chemical can splash or cause skin and eye irritation. This is one of the more common ways plumbing technicians get hurt on routine calls, and it slows down the job since we then have to handle it with extra caution and protective gear.
It often does not fix the real problem
Chemical cleaners can sometimes clear a partial soft clog, but they do nothing for the more common underlying causes of a recurring drain issue: a mechanical blockage further down the line, a bellied section of pipe, root intrusion, or a venting problem. If you have used a chemical cleaner and the drain is still slow or clogs again quickly, that is a sign the real cause was never addressed.
What to use instead
- A plunger, as described in our slow-versus-clogged drain article, for most minor clogs.
- A drain snake or auger for a clog a plunger cannot reach, if you are comfortable using one.
- Hot water for grease-related kitchen sink slowdowns.
- A call to us for anything that persists, recurs, or involves more than one fixture.
If a chemical cleaner has already been used
Tell your technician before we start work on that drain. It changes how we approach the job safely, and it is not something to be embarrassed about; it is very common, and we would rather know up front than find out partway through.
Need a hand? Harborline dispatch is 24/7 at (310) 555-0148.