Kohler flush volume (water usage)

[BostonGuido]

I have two 2016 Kohler toilets, labeled 1.28 GPF. They have the falling-float-on-a-stem style flush valve. They work fine and are properly adjusted. But they use about 2.5 GPF. Any ideas why this would be and if I can fix it? I want to reduce my water usage since I have a rain water cistern for all water needs. Is the "1.28" just marketing crap or are they really supposed to use this amount? It that the lowest possible adjustment for the flush valve, perhaps?
Thanks!

 

[FullySprinklered]

I have two 2016 Kohler toilets, labeled 1.28 GPF. They have the falling-float-on-a-stem style flush valve. They work fine and are properly adjusted. But they use about 2.5 GPF. Any ideas why this would be and if I can fix it? I want to reduce my water usage since I have a rain water cistern for all water needs. Is the "1.28" just marketing crap or are they really supposed to use this amount? It that the lowest possible adjustment for the flush valve, perhaps?
Thanks!

The fill valve has the float. The flush valve has the flapper. The "flapper" may be staying up too long. Could be a tower rather than the traditional flapper. Did two yesterday where the arm on the handle had some buildup or corrosion not allowing the tower to drop down as designed, wasting water. They were Kohler.

Others below are calling it cannister.

WD40.

 

[Sponsor]

 

[BostonGuido]

Thanks, fully. My bad on the terminology. Yes, it's a Fluidmaster fill valve, and a tower style rather than traditional flapper. Tower drops right down instantly so not hanging on anything. Water comes to the top of the tower (flush valve) when tank is full and fill valve shuts, but does not overflow. Still no idea why it uses 2x the quoted water per flush.
PS the photo above could be my tank - perfect!

 

[Reach4]

I would call Kohler and ask that question. https://www.us.kohler.com/us/static/customerSupport.jsp

A lot of people ask how to use more water, but questions about how to use less are rare as far as I can tell.

 

[BostonGuido]

I'll give it a shot but don't hold out much hope. I think that will step on the marketing or regulatory toes....

 

[Reach4]

I'll give it a shot but don't hold out much hope. I think that will step on the marketing or regulatory toes....

Asking to increase the water usage might step on toes, but I don't see that would happen for you trying to decrease the water usage.

I could see a plumber not trusting low-flow toilets and routinely doing some unpublished modification intended as a favor. Just speculating.

 

[BostonGuido]

I would call Kohler and ask that question. https://www.us.kohler.com/us/static/customerSupport.jsp

A lot of people ask how to use more water, but questions about how to use less are rare as far as I can tell.

I tried contacting them and first they asked for the model number, which I provided. Then they went dark. Has been 2 weeks now with no reply so I think they want to sweep it under the rug. Does anyone know if the 1.28gpf rating is a scam to pass a regulatory/environmental requirement or is it supposed to be real? Is it sort of like mlleage in a new car window, might be achieved under perfect conditions?

 

[John Gayewski]

Can you lower the water level in the tank i.e. lower the float so that it shuts off below the water line mark?

 

[BostonGuido]

Will give that a try. You twist the screw at the end of the the fill valve arm (that has the float on it), right?

 

[Terry]

Will give that a try. You twist the screw at the end of the the fill valve arm (that has the float on it), right?

WATER LEVEL IS TOO HIGH Turn the water level adjustment screw counterclockwise to lower the float. Flush to reset water level.

WATER LEVEL IS TOO LOW Turn the tank water level adjustment screw clockwise to raise the float. Flush to reset water level.