Need education on softener salt

[Buzzie8]

What purpose does the softener salt serve in a spot free system? I know it helps "soften" the water but need to know more. Mine seems to use a lot of salt (about 800 lbs a month). I know there are settings on the back flush but do not know why or what I should look for in making adjustments. Need some theory and pratical knowledge about the whole spot free reverse osmosis system and what rule water softening plays in the system.
thanks,
Buzzie

 

[I.B. Washincars]

The salt is for the water softener, not the spot free system. My knowledge of water treatment could fit on the head of a pin, but my simplified explanation for the salt is this, the salt cleans off the stuff that cleans the water.

 

[soapy]

Water hardness is calculated in grains. 0 grains hardness is almost perfect while it can range as high as 20+ grains. Your water softner tank will be listed as total number of grains. The tank (s) might range from 20,000 on up to several hundred thousand grains. Let say you have a 30,000 grain tank and your water is 10 grains of hardness. ( You can call your municipality to get a general range of hardness in your area) Your 30,000 grain tank would soften about 3000 gallons of water. 30K divided by 10 = 3,000. You are probably on a metered system for your softner so your tank would be set to regenerate between 2,500 to 3,000 gallons. THe salt brine will flush the calcium and iron particles that the softner beads filter out. Find out the size of your tank and the water hardness and you can figure out when you should regenerate your tanks.

 

[sparkey]

The water softener uses salt for ion exchange to charge the resin in the softener tank. The amount of salt your softener uses is a direct relationship to the amount of water that ends up in your brine tank. A given amount of water will dissolve a given amount of salt. There is an exact calcualtion to tell you how much salt a given amount of water will dissolve. If you suddenly use more salt it is an indication that you are using more water, like from a leak or more business assuming your water softener recharges from a set water usage, or something is malfunctioning in your watersoftener head letting to much water go into the brine tank when it calls for brine fill. The best thing for you to do is monitor the brine tank water level and make sure it is consistant and not over filling. If it overfills it will dissolve more salt causing more salt usage.

 

[MEP001]

Here's some more detail to some already good information. You can "brine" the resin bed at a rate of 15 lbs of salt per cubic foot of resin to maximize softening, or at 6 lbs of salt per cubic foot at minimum salt usage. The high-salt use will yield 30,000 grains of softening per cu. ft., the low-use will get 20,000. Unless the cost of your water is extremely high or you have difficulty getting rid of the waste, it's typical and more cost-effective to use the lower setting.

To make sure things are set properly you can either take the capacity in grains times .667 (Example: 210,000*.667=140,000ish) or the total cu. ft. times 20,000. Divide the softening capacity by the incoming hardness and you'll get the number of gallons it can effectively soften.

It's a little more involved in making sure you're not using too much salt. Most softeners refill the brine tank at a controlled rate and for a timed period. You will dissolve 3 lbs of salt per gallon of water, so the refill rate needs to be 2 gallons per cu.ft. or 30,000 grains of rated capacity.

 

[PaulLovesJamie]

good info provided so far...

Are you looking for general knowledge, or steps for how to determine if your salt usage is correct and how to adjust it?

My advice: get yourself a water hardness test kit from one of the suppliers, they're cheap and it takes all of 5 minutes to test your water. Test the water that comes in from the city (completely untreated by you) AND the water you wash with. Post the results here.
Also tell us how any gallons of water you soften per month
And what brand softener; specifically the model # of the control head. (including the size of the resin tanks).

Depending on your #s, 800 lbs/month could be too much or too little. How to adjust your softener for efficiency is one of those things we should have in the "saving $" section!

 

[Buzzie8]

Ok, thanks for all the great responses. I think I have TDS meter so I will check what my city water hardness is. I will also see how many grains my two softener tanks are rated at and then I will post again. I am assuming that the reverse osmosis in my spot free system provides secondary treatment of the already soft water. How does that fit into the equation?

 

[MEP001]

I think I have TDS meter so I will check what my city water hardness is.

You need a hardness test kit to determine the grains per gallon. A TDS meter checks for total dissolved solids, not just calcium.

I am assuming that the reverse osmosis in my spot free system provides secondary treatment of the already soft water. How does that fit into the equation?

It doesn't. It's a completely separate piece of equipment that only needs a supply of soft water. Once the softener is set up and working properly and efficiently, the only thing that affects salt consumption is overall water use.

 

[Washmee]

Ok, thanks for all the great responses. I think I have TDS meter so I will check what my city water hardness is. I will also see how many grains my two softener tanks are rated at and then I will post again. I am assuming that the reverse osmosis in my spot free system provides secondary treatment of the already soft water. How does that fit into the equation?

A TDS meter does not measure hardness of water. It measures the Total Dissolved Solids in your water which includes all minerals and contaminates. You need a water hardness test kit. It measures the amount of calcium and magnesium, which are the minerals that make water "Hard". After your softener removes the Calcium and magnesium, the R/O unit removes the remaining minerals and contaminates and you get essentially pure H2O.

 

[soapy]

My water hardness is 20 to 22 grains hardness an a TDS measurement of around 2000. After it goes through my softner the TDS is still around 150. The RO unit brings my TDS down to almost 0.

 

[Buzzie8]

Here is the latest:
1. I tested the hardness with some litmus type hardness tester I had (although the strips were old so I am not absolutely sure they are accurate) the results came back as 120PPM on city tap water. I also have a call into the local water authority to see what they will say about hardness.
2. I called the distributor for the water softener equipment. They asked me for the height of the 2 tanks (approximately 66") and the diameter (approximately 13"). They also asked me how much water that my RO system processes and what the model of the RO system was (Jim Coleman RO System). I did not know the answer to this so they said they would call my car wash equipment distributor to get this information. I am going to report back to them with the hardness info and they said they could probably figure out what the setting would be based on this information.

One of the harder things that I am trying to ascertain is how much treated water do I use each day or month from my overall usage.

 

[Jeff_L]

Wow. How often do you replace the membrane in your RO unit?

 

[Buzzie8]

Never in 7 years since opening. How often do these need replaced?

 

[Jeff_L]

Never in 7 years since opening. How often do these need replaced?

That baffles me. I would think with such a high TDS count before your RO system and a 0 count after it, you've got quite a filter system going on there. I just thought that your membrane would be getting filled up every year or so. I have to replace mine every 2-3 years. Your chlorine level must be very low, for that chemical will shorten your membrane life too.

 

[Washmee]

That baffles me. I would think with such a high TDS count before your RO system and a 0 count after it, you've got quite a filter system going on there. I just thought that your membrane would be getting filled up every year or so. I have to replace mine every 2-3 years. Your chlorine level must be very low, for that chemical will shorten your membrane life too.

The TDS of my water before the R/O unit is around 800. I went 8 years on a set of membranes. I have days where I use over 6000 gallons of spot free water.

 

[MEP001]

1. I tested the hardness with some litmus type hardness tester I had (although the strips were old so I am not absolutely sure they are accurate) the results came back as 120PPM on city tap water. I also have a call into the local water authority to see what they will say about hardness.

Get a Hach hardness test kit from Kleen-Rite. As mentioned before, testing the PPM is not testing hardness.

2. I called the distributor for the water softener equipment. They asked me for the height of the 2 tanks (approximately 66") and the diameter (approximately 13"). They also asked me how much water that my RO system processes and what the model of the RO system was (Jim Coleman RO System). I did not know the answer to this so they said they would call my car wash equipment distributor to get this information. I am going to report back to them with the hardness info and they said they could probably figure out what the setting would be based on this information.

Your RO system will be rated in gallons per day of production, but it will likely have a product flow meter, a reject flow meter and an hour meter. Using those figures and math will be the only way you can properly determine how much water it uses. As far as the softener settings, does it not have a meter to set the number of gallons it uses before it regenerates? If it does, you don't need to know how much water you're using, just the number of gallons the softener can effectively process before it needs to.

 

[MEP001]

That baffles me. I would think with such a high TDS count before your RO system and a 0 count after it, you've got quite a filter system going on there. I just thought that your membrane would be getting filled up every year or so. I have to replace mine every 2-3 years. Your chlorine level must be very low, for that chemical will shorten your membrane life too.

You may have something in your water that the softener can't remove. You might try a finer prefilter or send a sample of water to be analyzed. I haven't replaced the membranes in 7 years, and the TDS is still too low to register on my meter. The TDS of the softened water going to the RO system is around 1200.

 

[glennjude]

Do any of you sell your RO water in bottle form as an extra profit line