How to size a system
Start from litres a day, not from the model number. The range covers roughly 200 to 3,800 litres a day, and the gap between the ends of it is the whole decision.
Capacity is rated in GPD (US gallons a day), the industry's standard unit. In litres, the under-sink models make about 380 litres a day, the two-outlet commercial pair about 760, and the direct-flow units run into the thousands.
These are rated figures under standard test conditions. Real output falls as feed temperature drops and as dissolved solids rise, so size with headroom rather than to the exact number.
| Model | Output a day | How it dispenses |
|---|---|---|
| KB-C25R | 379 litres | Pressure tank |
| KB-C25R Plus | 379 litres | Pressure tank |
| KB-C25RH | 379 litres | ZenJar |
| KB-C25RP | 379 litres | Pressure tank |
| KB-C80R | 2,271 litres | Direct flow |
| KB-C100R | 3,785 litres | Direct flow |
| KB-C200R | 757 litres | Pressure tank |
| KB-C200RH | 757 litres | ZenJar |
| KB-A95R | 200 litres | Direct flow |
The question that actually decides it
Not how much water the site uses, but how fast it needs it. A pressure tank stores what the membrane has already made, so a kitchen drawing in bursts can run on a smaller system than its daily total suggests. A direct-flow unit has no tank and makes water on demand, which is why the commercial models are the ones sold to bars and restaurants.