By Matthew Baring-Gould, Kingscliff-based drainage plumber. Servicing Tweed Heads for 4 years. 5.0 stars across 173 Google reviews. Licensed NSW 383340C and QLD 15036450. ABN 74 605 392 348.
Recurring blocked toilet at a Chinderah property. Opened the inspection opening next to the toilet, found a square junction running back up to the toilet. CCTV’d the toilet waste downstream, no objects stuck, line was clear. Found the real cause: an offset pan collar had been used instead of a straight pan connector during the install, even though there was plenty of room for a straight connection. Offset collars catch toilet paper and cause recurring backups. CCTV downstream confirmed the rest of the sewer was free-flowing.
What the customer called us for
Owner called us back to investigate a toilet that was backing up again. Had been looked at before and the cause was never pinned down.
What we found when we got there
This is the kind of diagnosis you only get with CCTV. The line was clear. No roots, no cracks, no debris. But the toilet kept backing up. Running the camera up from the inspection opening showed the installer had used an offset pan collar between the toilet and the floor penetration, even though the toilet was positioned with plenty of clearance for a straight pan connector. Offset collars have a horizontal jog in them that catches toilet paper during a flush. Over time the paper lodges, water backs up, and you get exactly what this owner was experiencing.
Why we did it this way
A straight pan connector is a direct short vertical drop from the toilet pan into the floor penetration. Water and solids drop straight through. An offset pan collar introduces a horizontal jog to accommodate a toilet that sits off-centre from the floor penetration. The horizontal jog is a shelf where toilet paper can snag during a slow flush. Once a bit of paper snags, more paper snags on it, and you get a recurring semi-blockage that no amount of plunging clears for long. The right call when the toilet position allows: swap the offset for a straight connector. If the position does not allow, consider shifting the toilet.
What we did on site
- Attended site and investigated the toilet that was backing up.
- Opened the inspection opening next to the toilet and found a square junction up to the toilet.
- Ran the CCTV camera downstream through the toilet waste.
- Confirmed the waste line was clear of objects.
- Spotted the offset pan collar as the cause.
- Ran the CCTV further downstream through the main sewer.
- Confirmed the sewer was in free-flowing condition.
- Documented the offset pan collar issue in photos and video.
- Cleaned up the area on completion.
The result
Cause of the recurring blockage identified. The sewer itself is clean. The fix is to replace the offset pan collar with a straight pan connector.
If you have the same issue
If your toilet keeps backing up and nothing you do seems to fix it for long, it is worth getting a CCTV inspection before the next plunger session. Most recurring toilet blockages are caused by one of three things: (1) wrong fitting at the pan connection, (2) a backfall in the waste line, or (3) a cracked junction. CCTV diagnoses all three in half an hour. Call Matty on 0447 188 394 or request a quote.
Customer names and addresses have been withheld. Individual results vary. Drain Masters Plumbing is licensed in NSW (383340C) and QLD (15036450).
Frequently asked
What is a pan collar?
The fitting that connects the base of your toilet pan to the floor penetration where the waste goes into the slab. Comes in two main types: straight (direct vertical drop) and offset (a horizontal jog to accommodate a toilet positioned off-centre from the penetration).
Why would someone install an offset when a straight would work?
Usually laziness or a mismatch with the toilet being installed. If the toilet model changed after the floor penetration was cut, an offset collar lets you fit the new toilet without re-cutting the slab. Easier at install time, but it creates a weak point that causes recurring blockages for the life of the toilet.
How do you fix an offset pan collar?
Remove the toilet, remove the offset collar, fit a straight pan connector if the position allows, or re-position the toilet to align with the floor penetration. Takes a couple of hours including re-sealing the toilet base. One-off fix that eliminates the recurring blockage permanently.
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