Caroma Caravelle 2000 toilet, sluggish flush. Any ideas?
Posted by Wayner on January 25, 2004 at 16:29:19:
This toilet is installed on the 3rd floor of a building, and there is a definite water volume problem in the building anyway, so it's probably not exclusively the toilet's fault. Undersized water pipes are used within this building, and the building is probably built at, or slightly higher, than the nearest city reservoir, and it's on a hill. So, it's literally an "uphill battle" for water to reach the 3rd floor. We recently replaced the water pressure regulator at the city supply connection (in the basement). That made a big difference in water pressure & volume in the basement taps & toilet, which now splash water right out of the basin if the tap is opened fully. But this new pressure regulator made progressively less and less improvement to the taps & toilets on each floor above the basement. By the time the water reaches the 3rd floor, there isn't much difference at all on that floor from what was there before the new regulator.

Anyway, the original 3rd floor toilet had very poor flushing action, with water just trickling into the bowl during the flush. Since we had to flush about 3 times to clear it, we decided to replace it. We were talked into a Caroma Caravelle 2000, with a big sales pitch about the 4" trap solving all our problems. Well, no such luck. I'm pretty sure now that the problem isn't the drain, it's the water supply pipe into the toilet tank.

The pressure of the flush on the Caroma is pretty awful, just like the previous toilet. It gives a pathetic imitation of the Caroma-patented "guyser" on "full" flush, and oddly, there doesn't seem to be much difference when using the "half" flush button. If anything, the "half" flush is more powerful than the "full" flush. So we're having to flush the Caroma two or three times, too, just like the old toilet. No improvement, but lots of money spent, and lots of water wasted.

Is there anything we can do to provide a boost to the Caroma toilet flushes, short of ripping out all the walls and installing larger diameter water pipes in the building? Some kind of "booster reservoir" maybe?

I had hoped that the volume of water in the toilet tank would be all that the Caroma would need to create a powerful flushing action. Now it seems that it will not flush powerfully unless the tank inlet is under higher water pressure (or else has greater water volume)*during* the actual flush. If I'm wrong on this assumption, please correct me. But I didn't think the water supply pipe played any action in the flush itself (just in refilling the tank after the flush).

The water pressure/volume that passes through the toilet-tank supply pipe isn't wonderful, but it's not hopeless, either. The tank fills in a reasonable amount of time after a flush, and this bathroom's sink tap puts out an adequate amount of water (although nothing like the amount that the basement tap puts out - probably 1/2 the volume of the basement tap).

Help! Any ideas? Thanks!