Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
Now you mention it Ive seen many replaced with normal syphons. some work aftervavfashion but many don't...Anyone think it may be a siphonic pan playing up?
Can the OP send us a side-on photo of the pan then please?As Heliotrope has asked siphonic pan is a must to check it fits in with the dates.
Reply to the thread, titled "Toilet not flushing but not clogged" which is posted in Boiler Advice Forum on Plumbers Forums.
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