Drain services in Pomona

For grease, genuinely yes — and for nothing else. Dish soap with very hot tap water breaks down the fat film that coats a kitchen waste, which is the commonest kitchen blockage there is. It will do nothing whatsoever for hair, roots, scale or a dropped object. Two warnings: use hot tap water and not boiling, because PVC is rated well below boiling point and a kettle into a plastic waste is how a joint fails; and if it has not worked twice running, the build-up is further along than the method reaches.

By which fixture misbehaves rather than how badly. If one fixture is blocked and everything else runs normally, it is that branch. If waste comes up through the LOWEST fixture in the building — a shower tray, a floor drain, the downstairs toilet — when you use something elsewhere, the main line is blocked and every fixture above it is feeding the problem. Other tells: a toilet that bubbles when the washing machine drains, or several fixtures slowing over the same few weeks. If it is the main, stop using water in the building.

Three reasons, and the third is the one nobody mentions. First, what is in it: the common products are sulfuric acid or sodium hydroxide — lye. Second, the reaction is exothermic, and heat inside a closed pipe softens PVC and the solvent-weld joints holding it together, while corroding older metal. Third, and most practically: when it does not clear the blockage — which is most of the time on anything worse than hair — it does not go anywhere. It sits on one spot above the clog, hot, until somebody opens the trap underneath it. That somebody is usually a plumber, which is why we ask what you poured down before we start.

Yes, and the mechanism is heat rather than corrosion alone. The reaction generates enough warmth inside a closed pipe to soften PVC and the glue at its joints; repeated use leaves the plastic brittle enough to crack. On cast iron and older galvanised it corrodes from the inside, which on a pipe already narrowed by scale is the last thing it needs. One use on a well-made line will probably not destroy anything. Using it every few months, which is what people do when it half-works, is a different matter.