CSLB C-36 Plumbing ContractorService, Repair, and MaintenanceMedium
A homeowner reports that their toilet is flushing weakly, and the bowl does not fully empty, often requiring a second flush. The tank fills normally, and there are no visible clogs in the bowl or drain opening. What is the most likely cause of this issue?
- AAn incorrectly set water level in the tank.
- BA partially clogged rim jet or siphon jet.
- CA faulty fill valve.
- DA worn-out flapper valve.
Show answer & explanationAnswer & explanation
Correct answer: B. A partially clogged rim jet or siphon jet.
Weak flushing and incomplete bowl emptying, despite a full tank and clear drain, are classic symptoms of a partially clogged rim jet or siphon jet. These jets are crucial for creating the siphoning action needed for a powerful flush.
Why the other options are wrong
- A. An incorrectly set water level (too low) would reduce the volume of water for the flush, but the question states the 'tank fills normally,' implying sufficient volume.
- C. A faulty fill valve would affect how the tank fills, not the power of the flush itself once the tank is full.
- D. A worn-out flapper valve would cause a 'ghost flush' (water leaking into the bowl) or slow tank emptying, not necessarily a weak flush with a full tank.
Weak Toilet Flush Causes
Reasons why a toilet may flush with insufficient power, leading to incomplete waste removal or requiring multiple flushes.
- Clogged rim or siphon jets
- Low water level in tank
- Partially closed shut-off valve
- Vent pipe issues (less common for just one toilet)
Memory trick: Weak flush? Check the jets, they're the power bets!