All newer toilets use 1.6 gallons or less by law.
If you hold the handle down longer, it will drop more than that.
No adjustment is needed.
Hello, I recently installed a new Toto Drake and it's been working fine. My question is when I push and release the flush lever I get a partial flush (about 1/2 the tank empties). Push and hold fully empties the tank. Is this the design of the toilet (liquid vs solid) or have I got the flush lever adjusted? Thanks...
I like to think of that as a feature, not a problem. For liquid waste only, a quick push-and-release uses under a gallon on my Drake, but for heavier loads, the push-and-hold release will use more water, but provide a more complete clearing of the bowl. There are "dual-flush" toilets out there that charge for this free Drake feature.
Let's be clear here...the Drake is designed to dump about 1.6g on a flush. To do this, you need to push the flush lever down fully, but not hold it. If you don't push it down fully, it won't stay up on its own to allow the normal flush volume. This is true with many toilets. A quick flick won't allow it to do its thing as designed. Holding it down until the tank empties defeats the purpose of the low-flow toilets, and for nearly 100% of the time, is a waste of water...the Drake, and most of the better toilets DO NOT NEED more than the design water volume. So, if you 'flick' some but hold it down to empty the tank on others, you'll likely end up using more water than if you did it as designed for each flush.
Let's stop calling this a 'feature', since it isn't and can lead to waste, which we are trying to avoid. It isn't unique to this line of toilets, either; my old 3.5g job (non-Toto) would do the same thing.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014
Well, that may be how it's designed, but it's not how mine works. I guess there are 3 modes: push to the stop and immediately release uses about .9 gallons and cleans the bowl; push to the stop, hold for an indeterminate but very short time, uses about 1.6; push and hold until you're happy with what you see, and you can use the entire tank.