In your diagram, the valve just before the filter is a shut-off not a bypass. You never mentioned the pre-filter before... what are you filtering? what size is the filter? What element is inside? Does it have adequate flow as to NOT impede the house water pressure and flow? If there's a good reason to install the filter then install pressure gauges before and after the filter so you can see the pressure drop and know when to change the filter element. Close the open resin bag and keep it clean and dry. I'd assemble the softener and get it plumbed, check for leaks and correct operation, and then program it.

Increasing the occupancy from two to seven people it's no wonder the old softener can't keep up and no amount of servicing will get it to. It is seriously undersized. IMO, you are not getting the best bang for the buck, With Kinetico you get an excellent softener with a couple reservations. If you have a good Kinetico dealer then Kinetico can be a good choice and they have built a loyal customer base but you will be locked to your local Kinetico dealer and their product, parts, and service pricing policies. You should be able to get a correctly sized (based on water conditions, occupancy, bathrooms, and appliances) and efficiently set up industry standard softener and acid neutralizer for roughly half the cost of the Kinetico products if you can find a competent independent water treatment pro in your area. With an industry standard softener tech info is readily available for download (not with Kinetico) and parts are available all over the net (not with Kinetico) and there always seems to be people locally who service and sell parts for Fleck control valves. Before you grab your checkbook you should investigate all your options and then make an informed decision whichever products you choose.

To "soften" water is to remove calcium (among other things like iron) from water, not calcium deposits from pipes, and that is commonly done by one of two methods. One method is ion exchange as done by a water softener. A water softener exchanges either sodium ions (if using NaCl) or potassium ions (if using KCl as a SALT SUBSTITUTE) for calcium (and other) ions in the hard water. That's it, no ifs, no ands, no buts, and no sales double talk. Simple chemistry and physics. Softening water is not black magic. It is physics and chemistry with a side of mechanics. No matter how hard sales people try (and want) to they can not violate the laws of physics or change the nature of chemical actions and reactions. The other is by a filter and/or membrane technology or distillation, but no simple filter will remove calcium. You would need a reverse osmosis unit large enough to service your entire house. You would not want to pay for that big an RO nor pay for the service and routine maintenance it would require and RO water would be very aggressive in your plumbing and it would waste a lot of water. NO magnet(ic) gizmo or electronic gizmo or "conditioner" or salt-free conditioners (that should not be called softeners because they are not) will soften water but people waste their money on them EVERYDAY. Check out this URL for one story http://www.nmsr.org/magnetic.htm and there are many more on the net if you Google. If you're on a water system the water utility can supply you with the specs of the water AS IT LEAVES their facility but that is not necessarily representative of the water conditions at your water meter. Hit the Yellow Pages under water treatment and call at least three local water treatment professionals. Make sure you call at least one of the big dogs like Kinetico or Culligan for comparison and at least a couple independent pros. Give each an opportunity to offer suggestions and provide you with a quote to meet your water treatment needs. IGNORE ANY THAT DON'T TEST YOUR WATER THEMSELVES as they can't speak intelligently to water treatment without knowing what needs to be treated. Ask lots of questions. Softening the entire house or just the water heater (bad idea)? Warranty, parts & labor or just parts, how long and on exactly what? Install, permits required, licensed plumber? Routine maintenance and costs? Do they stock parts? Response time for emergency (water leak) calls? If they don't explain things to your satisfaction that is a good indicator of how you'll be treated after the sale. Are all your treatment needs being addressed? Ask your neighbors if they have any water treatment experience. They might tell you who's good or who to avoid. Come back here and post the specific recommendations and hardware components with the costs and we'll give you our opinions. If you're a DIYer then you have other options but remember, when you do it yourself there's no one else to blame.

Milo, It's good to start your own thread instead of hijacking someone else's. I disagree quite a bit with Delray, I can't tell exactly what's going on with that particular unit but you don't want to mix media in your unit - in other words, you don't want carbon media in the same tank as the resin for the softener. You want those to be two different units. Different media have different backwashing requirements and lifespans. If you want a water softener, buy a decent water softener with an industry standard control valve (Clack or Fleck). If you want a carbon filter, decide if you need a simple cartridge type filter for drinking water (what I recommend) or a backwashing whole house filter. If you have a specific contaminate that can only be removed with reverse osmosis then get a separate unit to do that - usually only for drinking water. Whole house R/O is crazy expensive to buy, operate and maintain and is over-kill for virtually everything unless you need to remove a specific contaminate for drinking water. Most people don't need an R/O filter - even for drinking water. Keep in mind that R/O water is aggressive to metal plumbing unless minerals are added back in. I also disagree with: "whole house water filtering has to be fairly robust to last - that is why they are expensive. Kinteco (and others) make water filtering for restaurants, mfg plants etc and that is expensive since those businesses can't afford any breakdowns..." This is pretty bogus. We are talking about residential water treatment - not commercial treatment. A good quality residential water softener is about $600 online with an industry standard Fleck valve and no smoke and mirrors. That's the cost of the unit. Doesn't include installation and maintenance. A backwashing carbon unit with 1.5 cf of GAC is $500-600, again with a Fleck valve. A cartridge unit for drinking water will cost about $100 + $30 a year for the cartridge.