From 
Gravity Flush
This is the system toilets
have used for over a century: The flush valve or
“flapper” opens and water rushes down through the
bowl. Manufacturers have steadily improved tank and bowl designs
to create a more powerful flush with less water. One of the most
effective improvements was to simply enlarge the flush valve from
2 in. to 3 in. or more.
| Pros: |
| •Cost. Some of the models that perform well in lab tests
cost as little as $150. •Easy to maintain. Diagnosing problems and finding replacement parts is relatively easy. |
| Cons: |
| •Tanks can sweat. If condensation forms on the tank of
your current toilet, the same problem will likely occur with any
gravity toilet. •Big differences in performance. There are still a lot of wimpy flushers out there. You have to do your homework to find a model that performs well (see “Toilet Tests,” left). |
Pressure
Assist
These toilets have a
pressure tank inside that works like a big water balloon. Water
fills the tank and is held there under pressure. When the flush
valve opens, pressure and gravity combine for an explosive
flush.
| Pros: |
| •Powerful flush. When it comes to clearing the bowl of
solid waste, pressure-assist models generally outperform other
types. •No sweat. Because water is held inside a pressure tank rather than the porcelain tank, condensation won’t occur on the outside of the toilet. |
| Cons: |
| •Cost. Starting at about $240, pressure-assist models
cost more than some of their cousins. •Repairs. Diagnosing problems, finding parts and making repairs can be a headache. •Noise. Pressure-assist toilets create a loud flush. |
TIP: Pressure-assist toilets are common in public rest-rooms, so you can take one for a test drive at an office or business. Just lift the tank lid and look for the pressure tank to see if it’s a pressure-assist model.
Vacuum
Assist
This is the latest flush
innovation. The porcelain tank contains a vacuum tank
that’s connected to the trapway (the large tube that carries
water out of the bowl). When the toilet is flushed, water flowing
out of the tank creates suction in the vacuum tank and trapway to
help suck waste out of the bowl.
| Pros: |
| •Easy repairs. Vacuum-assist toilets use the same type of
fill and flush valves as gravity models, so they’re
simple to repair. •Strong flush. Vacuum-assist toilets do well in lab tests. In clearing solid waste, they outperform most gravity types, but don’t do as well as many pressure-assist models. •No sweat. Like pressure-assist models, vacuum-assist toilets store water in an inner tank, so condensation won’t form outside the porcelain tank. |
| Cons: |
| •Cost. Starting around $180, vacuum-assist models cost
slightly more than some gravity models. •Limited choices. There are currently only two vacuum-assist toilets from major manufacturers: Briggs’ Vacuity (www.briggsplumbing.com, 800-888-4458) and Crane’s VIP Flush (www.craneplumbing.com, 800-877-6678). |
My Crane VIP toilet was well rated in Consumer Reports when we built our house in 2003. But now that we have a tank leak problem, it seems to be a 1 time/has-been wonder, with no info or support as to how to fix. It is an oddity, as shown above. Since it's no longer made, and Crane has since been bought by American Standard, help does not look hopeful. Would love to hear otherwise before buying a whole new toilet. Can the current "guts" be removed and another system installed in the tank?
waist of my time
This article has a very misleading title. I expected to find information on improving my current toilet(s) performance and all this article does is talk about three types of toilets with which I could REPLACE my current toilets. The title also says "Step-by-Step Instructions and Pictures" but there are NO instructions at all in this article, just information. I gave it 1 star.
I was looking for information on how to free up a sticking float. The float works but just on a delay since it sticks. I tried many house hold products and some lubes, but to no avail. I really didn't see any step by step instructions in this article.
Why not include useful information to tune up your existing potty--like for instance--USE A clothes hanger to open the top rim flush holes that have been clogged with mineral deposits over the years. Also, vac all the water from the bowl and pour a gallon of vinager in the bowl for 24 hours. Things that actually work to improve the "old" style potty that always work----IF MAINTAINED.