I am looking for documentation from the resin manufacturers. Purolite, Sybron, etc, Ohio Pure Water is a great group, but it is also nothing more than an internet company that has other companies drop ship product for them.
If the documentation exists, great, but regardless, GE, Culligan, Rayne, Puronics, Seimens, and virtually all other companies that do portable exchange, which is nothing more than regenerating the resin off site, all try to run 30 day routes. That being said, there are also many protocols for regeneration plants, including water reuse, brine reclamation, etc, so it is not a true apple to apples comparison.
My real question is, assuming a decent iron free water supply, what is going to happen if the resin does not regenerate every 14 days or more? And using my earlier example, what is the proper way around the massive salt waste that would occur if you forced a system to regenerate every 14 days if it only needs to regenerate every 30?
With over 25 years of commercial, industrial, and residential experience, dealing with water and systems from all over the world, I will give you the simple answer. Nothing. It is fine to regenerate less frequently than every 14 days. The original 14 day idea is an old idea, written many years ago that has been cut and pasted for decades into companies literature. I have some great old literature that goes over the proper method of installing a softener, basically mandating that toilets must be bypassed. That old idea was finally abandoned a little over 20 years ago, although it still pops up from time to time. Most internet websites simply copy other websites literature, change a few words and voila, they are a "knowledgable" water treatment company. Sort of the same way some people try to take credit for the sodium in water to white bread analogy, or a can of baked beans. I heard those my first day of training, and to this day, people use those examples like it were their own.
I have searched for a long tim e for the resin manufacturers to make any recommendations on regeneration frequency. It does exist on certain other medias, KDF, Pyrolox, Filox, Birm, etc, but resin, and most other medias do not. They have pages of information on regeneration capacities, flow rates, pressure curves, temperature ratings, pH ranges, freeboards, expansion rates, regenerant capacities based on regenerant, etc.
All that being said, I think what is missing in this conversation is some guidelines. If you have water with turbidity issues, regenration frequency will be more important. Iron in the water... salt quantity and regeneration frequency are important, no water flow at all, (vacation home), regenerations should be done to prevent the stagnent water issues. For my vacation home, I have it set to regenerate every 14 days, but I change the salt setting to almost nothing unless it is occupied. A good clean water supply, why would frequent regeneration be necessary? What would happen if you went past 14 days?
This idea is similar to the flow controls on RO debate. The old idea of a 4 or 5 to 1 ratio is still practiced, even though membranes now cost 1/5 of what they used too. Is the extra water waste worth trying to eek out another 6 months from a membrane? Your membrane will last 4 years instead of 4-1/2. If you have a softener, is it really necessary to have that bad of a ratio. Sorry, going off into a different area but I think the ideas from this industry that are still hanging in there from 25 years ago need to be addressed.
25 years ago, meters were a "neat but expensive" item, and were rarely used, and the salt settings were 10-15 pounds per cu. ft. Now we are pushing 3-8 pounds of salt per cu. ft., and very few companies would even consider not using a meter, and in many states, it is not even legal to install a residential timeclock softener. Reputable distributors wont even sell single tank large commercial systems if they know that is improperly designed and highly wasteful in order to save a few dollars up front.
The most recent article from Purolite written over a decade ago I have read that discussed resin regeneration frequency went both ways on the idea. Frequent regeneration leads to shorter resin life due to osmotic shock, lowering salt amounts and not allowing the resin to become completely depleted could protect the resin from the damaging affects of this problem, later in the same article it recommends increasing the regeneration frequency if fouling is a problem, iron, sediment etc.
The article never did set what the frequency should be.
Sounds reasonable to me