Had the same issue with a Caroma setup—half flush barely did anything, full flush worked fine. Turned out the cable was just a hair too tight, so the half button was actually pulling both mechanisms at once. Loosened it a bit and suddenly it worked as intended. Those tolerances are way fussier than you’d expect. And yeah, I’ve had to improvise spacers too... seems like every “universal” button is just a little off.
Yeah, that’s a classic one with dual-flush setups. Here’s what I’ve seen cause half flush issues more times than I can count:
- Cable tension is a big deal. Too tight or too loose and the half flush won’t trigger right—sometimes it’ll even pull both valves like you said.
- Those “universal” buttons almost never line up perfectly with the actual mechanism. If you’re not getting a clean press, it can throw off the whole thing.
- Spacer improvisation is basically standard practice at this point. I’ve cut bits of plastic or even used washers just to get the button sitting right.
- Sometimes, the rods/buttons are just a hair too long or short for the cistern lid. Even 1mm off can mess up the flush.
Honestly, manufacturers could make this a lot easier, but here we are. If you’re still having trouble after adjusting cable tension, check if the button’s actually pressing straight down on the mechanism—sometimes it’s just slightly off-center and that’s enough to cause issues. It’s fussy work for something that should be simple... but that’s plumbing for you.
Half flushes are the bane of my existence, I swear. I’ve got a couple rentals with those “eco” dual-flush toilets and every time a tenant calls about a running toilet, nine times out of ten it’s the half flush acting up. One time I spent an hour fiddling with the cable tension, thinking I was some kind of plumbing wizard, only to realize the button was just barely nudging the mechanism at an angle. Not even a millimeter off, but enough to make it useless.
I’ve actually had better luck with the old-school lever systems—less fancy, but at least you know what you’re getting. The universal buttons never seem to fit right either. Had one where I ended up stacking two washers and a bit of cardboard just to get the thing to press down straight. Felt like I was building IKEA furniture inside a toilet tank.
Is it just me or do these things seem designed to make you question your life choices?
Honestly, I get where you’re coming from, but I’ve actually had the opposite experience with dual-flush setups—at least with the higher-end brands. The cheaper models are a pain, no doubt, but the better ones seem to hold up if you take the time to install them right and use OEM parts. I’ve noticed a lot of issues crop up when people try to mix and match universal buttons or replacement valves. The tolerances are just too tight for that kind of improvising.
I do agree, though, that the cable mechanisms can be finicky. One rental I look after had a button that would stick every other week until I swapped out the whole assembly for a new one. Since then, it’s been fine. I guess my take is, if you’re going to use dual-flush, it’s worth spending a bit more upfront and sticking to the manufacturer’s parts. Otherwise, yeah, you end up MacGyvering with washers and cardboard... which is never a good sign.
I swear, these toilets are either the best thing since sliced bread or a total headache. I bought a mid-range dual-flush when I moved in, thinking I was being all eco-friendly and smart. Half flush? Might as well be a gentle suggestion to the water, because it barely does anything. I tried swapping out the button (universal one from the hardware store), but that just made it worse—sometimes it wouldn’t reset, sometimes it’d stick halfway and just hiss at me.
I totally get what you’re saying about mixing parts. The moment I started fiddling with non-OEM stuff, it turned into a science project gone wrong. Eventually caved and ordered the actual manufacturer’s kit... not cheap, but now at least it works like it’s supposed to. Still, I don’t trust that cable for a second. Every time someone visits, I’m half expecting them to yell for help from the bathroom.
Moral of the story: dual-flush is great if you stick with what the brand intended. Try to get clever with “universal fit” parts and you’ll be knee-deep in YouTube plumbing videos before you know it.