Hi All,

I have fitted a new bathroom sink and the run to the main waste is around 4m. It gurgles so decided to switch the existing bottle trap for an anti-siphon one.

https://www.screwfix.com/p/mcalpine-...ite-32mm/37314

What I thought would be a 2 minute job...... The anti-siphon one is much deeper than the current one and unfortunately the drawer of the cupboard under the sink hits it - it is probably about 10mm too deep. I have looked around the web and it seems like they are all the same depth (approx 120mm from the centre of the waste pipe to the bottom). So to fix the issue I have the following thoughts although none really good...
1. The bottom of the 2 traps look like they are interchangeable so I could swap them. However the bigger one has a plastic pipe which goes down the centre of the bottle bit. I suspect this is key to the anti siphon bit. I could cut this to enable the shorter one to fit but suspect I may be back to gurgling
2. I cut 10mm off the chrome waste thread to lift the lot up. From a waste perspective that would probably work but the chrome waste is silicone in so would be a bit of a pain and also cutting it smooth and straight to ensure a good seal would be difficult
3. Fit an inline anti-siphon valve and use the original trap. This is a bit of a pain so would ideally not go down the route.

Anyone have any bright ideas?

thanks

Lee.