Our guest bathroom commode makes a loud fog horn sound when flushed. It's startling to guests and embarrasing to my wife and I, as you would imagine. What might be causing this and what can we do to fix it. Thank you.
The first thing I'd do, Jim, is remove and replace the fill and flush valves in your toilet. The sound may very well be from the fill valve, but I'd still replace both. To clarify, the fill valve is the piece that goes up and down near the handle, and has the floater attached. The flush valve is the flapper. A bad valve can vibrate and make those sounds. Another thing you can try: Sometimes pipes vibrate when water runs through them, so make sure plumbing pipes are secured tightly to framing. If this toilet happens to be on a first floor, make sure pipes are well- attached to floor joists to minimize vibration that occurs when water runs through.