Top water inlet too low/cut cistern??

A while ago we bought a new Kohler Opiaz Back-to-wall Toilet Suite for our bathroom renovation. The plumber was supposed to fix the water pipe in the wall for the top water inlet at 775mm high from the finished floor height.

The plumber set it at 757mm from the finished floor. Needless to say, the pipe sticks out of the wall into the back of the cistern (see photo). (Long story short - we fired this plumber before he completed the work, and the new plumber just continued from where he left off, not knowing that the old plumber messed up).

We cannot find a toilet to replace the one we bought due to all of the variances between toilets (nothing out there will fit all three factors of top inlet location - vertical and horizontal - and the drain set out 'S' of 100-150mm.

We just finished all of the porcelain tiling over a rendered brick wall and a full slab floor. We do not want to rip it all out and move the pipe. We were thinking about getting a diamond core drill bit (30 or 40mm) and cutting a hole in the back of the cistern and then silicone the hell out of it.

Questions: Is this completely mad? Will the water line likely reach our hole and make a mess? How would you cut the vitreous china - drill a hole or saw?

Any other thoughts? Any advice much appreciated.

Is that a Caroma toilet tank in Austrailia?

Check the height of the flush valve to determine if the lowered hole will affect that first.

If you have the height, then maybe you could cut a hole lower in the tank.

It's a Kohler in Australia

Sorry - being an American in Australia, I probably had some subliminal thing about Kohler! Plus it was cheaper (on sale) than the Caroma!

Thanks for your opinion. I don't think it should be a problem as it is adjustable, but I will check first.

I bought a diamond core drill bit, and it arrives later this week. I will let you know how it works out.

I promise that from this day on, I will never opt to have a new toilet and plumbing installed with a top inlet! What a nightmare!

Great site by the way. Thanks!

Alternatives

I get antsy drilling into porcelain, even with diamond saws; I'd treat that as a last resort. Earlier resorts:

1) I assume there's not enough room for a pair of 90s to raise the pipe coming in to the cistern?

2) You could have a small periscope-like thingy fabricated to mate with the pipe coming out of the wall on one end, and provide a higher nipple into the cistern on the other end.

3) Worst case, it looks like you might only have to remove one tile behind the cistern to gain access the the pipe, if a plumber should think raising the exisiting pipe is reasonable.

I like (2). A good sheet-metal man could braze a brass female fitting into the side of a brass nipple with a cap or brazed seal on the bottom, and a regular 90 on the top. This, of course, depends on the amount of room available between the cistern and the wall. All done up nicely and polished, it might even look good.

Drilled the hole in the dunny

Mikey - there was NO room in the back to do a 90 degree angle thing, especially as it would have messed with the toilet sitting flush to the wall. I liked the idea of making it a periscope-like feature. Never thought of that, wish we did last week when I had the time to look into that.

We did mess with the idea of building a wall out and doing an in-the-wall cistern thing, but the bathroom is really too small for that and the shower door would hit the toilet then.

So - we drilled. Took ages because we didn't wish to crack the thing, we used a 35mm diamond core bit with a pilot bit in the middle. Will post the final result photos.

Hopefully this will be the answer, because what is done is done! No going back now! Maybe this post will inspire others out there to DOUBLE CHECK THE LEVEL OF THE INLET BEFORE YOU TILE!!! Lesson learned!


PS - you can see the water line in the photo - centre of the tank, near the white plastic piece. Plenty of room above.