Duplex plumbing mystery

[Jeff Dawson]

Duplex tenant called yesterday, both tubs and toilets backing up. Fortunately the 6th and last plumber I had a number for was able to get over there yesterday evening. It was a quick fix as there was a piece of 5-6" long PVC inserted in the clean out. Of course this is odd in itself but it also had a wire loop attached to one end. This is one of 25 duplexes built in the mid 80's and the plumber said they have found these in 6-7 units there. He has no explanation as to why so I'm still scratching my head this morning.