Unusual water softener layout advice

[MstrCarpenter]

            The installation is at a Church. We have a shallow well pump connected to a driven well point into the aquifer. There is plenty of water but frequently the pump/well could not keep up with demand. To have ample reserve, the pump's 1" NPT discharge increases to 1-1/2" copper connecting three 118 gal. pressure tanks before reducing to a couple of 1" and 1-1/4" branches. When the softener was added downstream from the pressure tanks it created a new bottleneck, basically eliminating any benefits of having a reserve.
I asked our "water treatment contractors" if they honestly thought their tanks plumbed with 1" PEX along with a dozen or so PEX-B 90*'s could provide enough flow for 13 toilets, 9 sinks, a commercial kitchen and a 2 bedroom house. They agreed the treatment should be before the tanks.
            Everything was disconnected and relocated. The tanks, pump, pipes were cleaned and flushed and re-connected. Got many compliments on the new layout and quality of workmanship; including some from those contractors. They showed up today as scheduled to do their part of the re-install. Everything is good until the installer calls this afternoon and tells me it's all hooked up but it should be installed after the expansion tanks! Their system won't back-flush correctly. Now their only advice to fix is to add a check valve and another expansion tank before their system. This is where I ask for advice. Their system is connected to a 1" tee above and below a 1-1/2" ball valve. I would prefer to not re-work the 1-1/2" copper if possible. Any and all suggestions are appreciated.
 

[blackhat]

You jumped in right up to your armpits didn't you. Did anybody bother to note the backwash requirements in both gpm, total gallonage and minimum pressure for this softener or the flow rate it needed to provide? Did anybody test the pump and source to see what it could provide, with or without the pressure tanks? You might end up better off with a softener that fits your pump and well feeding into a clean water reservoir and a second pump feeding the loads.
There are so many variables I can't see that any further advice would be reckless. Don't pay the clowns a penny yet.

[MstrCarpenter]

You jumped in right up to your armpits didn't you.  Did anybody bother to note the backwash requirements in both gpm, total gallonage and minimum pressure for this softener or the flow rate it needed to provide? Did anybody test the pump and source to see what it could provide, with or without the pressure tanks?  You might end up better off with a softener that fits your pump and well feeding into a clean water reservoir and a second pump feeding the loads.  
There are so many variables I can't see that any further advice would be reckless.  Don't pay the clowns a penny yet.

This is basically what we're doing except the "clean water reservoir" is under pressure. The water treatment system, now treating for both iron and PH, was originally installed on the main after the tanks. Re-locating it between the pump and storage tanks works as intended and meets our peak demands. However their system does not automatically "by-pass" during regeneration, which reportedly will send the back-washing water the wrong way. If  we put a check valve on their outlet, and a short loop from the "treated side" to the "untreated side" (with a check valve) the water would at least have to flow in the right direction. The new problem is they said you don't really want to be flushing the toilet while its back-washing; which means (if the pump happens to cycle during regeneration) the three tanks will be topped off with water we don't even want in our toilets.

Adding a pressure tank before the system will be closer to what you proposed, with the added benefit of drawing untreated water from our sillcocks. Currently, this is the plan. I still don't like (or trust) that their system doesn't automatically by-pass during back-wash. I'm equating it to back-washing my pool sand filter, sending the dirty water to waste but, at times, back to the pool as well.

[aquaticjim]

This is basically what we're doing except the "clean water reservoir" is under pressure. The water treatment system, now treating for both iron and PH, was originally installed on the main after the tanks. Re-locating it between the pump and storage tanks works as intended and meets our peak demands. However their system does not automatically "by-pass" during regeneration, which reportedly will send the back-washing water the wrong way. If  we put a check valve on their outlet, and a short loop from the "treated side" to the "untreated side" (with a check valve) the water would at least have to flow in the right direction. The new problem is they said you don't really want to be flushing the toilet while its back-washing; which means (if the pump happens to cycle during regeneration) the three tanks will be topped off with water we don't even want in our toilets.

Adding a pressure tank before the system will be closer to what you proposed, with the added benefit of drawing untreated water from our sillcocks. Currently, this is the plan. I still don't like (or trust) that their system doesn't automatically by-pass during back-wash. I'm equating it to back-washing my pool sand filter, sending the dirty water to waste but, at times, back to the pool as well.

I am not aware of any automatic valve system that does not open a bypass once the regeneration is started.  Please list the brand and model number of the control head/valve.  As for your assumption of the backwash water, the automatic valve creates a path from the pressurized line, through the down comer pipe to the bottom of the resin bed, up through the resin bed and to a drain. So unless your system is really strange, it should not matter for regeneration if the storage tanks are before or after the softener.  However, service flow rates are important based on the treatment system.  You did not say what the well flow rate is.  Assuming it can flow 20 GPM, that will take a larger softener than if the softener was downstream of the tanks where 20 GPM is very uncommon.  Again, what is the diameter of the resin tanks?  Finally, you say the new system treats for iron and Ph?  How?  What are you adding to the raw water to treat for these two items?  A typical cationic resin bed only removes some dissolved iron species.

[MstrCarpenter]

The three large tanks were installed when we built a large addition with an increase from 4 toilets to 10 toilets + 3 urinals. I don't recall if the softener was added just before or after that time. We did however ruin a Super Store in about 5 years due to high PH, so they added a tank to treat that. I also agree that the system should by-pass. They said it doesn't. I just can't put blind faith in our current Contractor. Some people over at Terry Love's plumbing forum are educating me and trying to point us in the right direction. If you're interested, it's in the "water softener forum" with the same thread title.