I have been researching water softeners and I seem to hear a lot about variable brining but there is not much information on how well it works, or if this should be a factor to consider when purchasing a water softener albeit one exception. I have seen on several boards that variable brining as it pertains to the Fleck 7000 is basically a hoax and that it does not save salt (might actually use more salt) and that this features uses 2 to 3 times more water than without variable brining. The problem I am having is that all the negative information on variable brining is coming from one individual that seems to be on all the information boards. He is selling another valve (I think it is the Clack valve). So is this person giving out correct information or is he just giving disinformation to push his product? Confused.
Answer: Some truth & some mistruth – takes quite a bit of education to correctly understand this process.
We offer both the Fleck 7000 and the Clack control, and the truth is that while both of these are very good valves, neither is really designed for extreme salt efficiency. It’s not that they are not good salt efficient controls, it’s just not their primary design purpose. One thing to understand, that variable brining only effects salt consumption during regeneration, not water softener performance.
First the Fleck 7000. This control can be programmed to have variable brining. Variable brining means that the unit measures the amount of the resin bed that is exhausted, and only uses as much salt as is required to regenerate the exhausted portion of the bed. Variable brining for the 7000 is only available as a “meter delayed” mode. This means that the control will automatically calculate a reserve capacity when this option is selected. Reserve capacity means that when the softener is factory set to normally regenerate at (for example) 2:00 AM, and there is some water usage at 2:15 AM, the softener will determine that a re-generation is necessary. However, the unit will not regenerate until the following night at 2:00 AM. You need to make sure that in this case you have the extra capacity (reserve capacity) to carry you through the next day.
In variable brining mode, the 7000 continues to measure how much water is used during the full day of regeneration, and adjusts the brine tank water refill volume so that only the correct amount of salt is used. So, with this feature enabled, the amount of salt savings would be the difference between the standard pounds of salt used for regeneration, minus the amount calculated with the variable reserve feature selected. This reduces salt consumption to some extent, but really does not translate into much of a salt savings in a typical residential application.
Now the Clack WS1. The Clack control is indeed an excellent control, but it is not available with a variable reserve. However, it is available in an up-flow (counter-current) design. Up-flow designed softeners can be more salt efficient, as the high concentration (saturated) salt solution meets the most exhausted portion of the resin bed first during the regeneration process. This maximizes salt utilization during regeneration, and allows for reduced salt dosage. However, while this will save a few pounds of salt, up-flow design is mostly an advantage in performance for specific applications requiring removal of higher levels of iron, manganese, etc. – and not really meant for the reduced consumption of salt – although it will use somewhat lower amounts of salt.
There is a design that combines both of the features mentioned above, it’s a countercurrent (up-flow) brining softener with a variable reserve feature. It’s featured in our WS2FM softener (Aqua-Pro 5000 control). This is a top performing system – and as salt efficient as it gets – but primarily designed for markets where reduction in salt consumption is very important. If you do not reside in one of these localities, then the extra expense in purchasing one of these units may not be justified.