How Waste Traps, P Traps, Bottle Traps and U Bends Work | DIY Doctor
Sink won't drain. Removed U-bend, not clogged. Rotated right-angle bend upside down and able to pour water down. Live in a flat. Bathroom all works fine. Haven't tried dishwasher / clothes washer
How to Fix a Leaky Sink Trap | HomeTips
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