I note your answer "diaphragm split in the syphon. fit new syphon and it will work fine". Please excuse my ignorance (I'm an elderly lady with no experience in DIY) but where will I find the diaphragm in the syphon? Would I be able to replace this part myself or will I need to get a plumber? I know how to turn the water off going into the systern. Thank you for your help.
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