With nothing using water in my house besides my geothermal unit running, My water softener shows there is water going through its meter. This is strange because the only way this could be happening is if my geothermal is pulling water and causing my water softener to reverse flow. It turns out to be about .5 gallons a minute, that my geo is leeching from my water softener. Has anyone else had this problem?

If there is reverse flow, you can install a check valve.

is this an open loop?

Yes this is an open loop.

I actually received a call from a retired plumber who works with the manufacturer of the water softener. He gave me a couple of options. 1st, since he doesn't think the geothermal is actually using the soft water, but instead, the changing of the pressure in the house is causing the water to move back and forth when the pressure drops and when my water pump kicks on, he said I can over ride the metered softener and just soften my water every 3 or 4 days instead.

2, install a check valve on the inlet to my water softener, but he said I must also install a heat expansion thing on the inlet of my water heater.

3, get a new constant pressure water pump. About $3000


My idea is maybe purchasing a small inline constant booster pump that I can install in front of my water softener. Set it at 60 psi and enjoy the constant pressure at all my faucets. I'll have to check cost for this options

Thanks all who responded.

Option # 3 will be the most expensive check valve you ever purchased. Correct diagnosis is the best course of action here, or you are throwing solutions at a problem you may not have. Isolation valves, check valves and T eeing in some pressure and vacum gauges will give you a garaunteed dignosis.
YMMV
Eric

although i am a big fan of the constant pressure systems from Grundfos with the CU-301 controllers, i do believe it may be overkill ( until a new water pump is needed). This could be something as simple as a very small leak in a toilet, a stuck valve inside the water softner itself that is flowing to drain. Install a check valve on the inlet and call it a day. What brand water softner do you have?

Before casting about for solutions, be certain you actually have a problem.

The water softener uses the Clack ws-1 valve. The problem is when the geothermal is running, my water softener is showing it is being used. This also happens if I open up the valve that is by my storage tank and I dump water in my sump pump. It is pulling water through my water softener in reverse.

If I turn off my Geo, the water softener works fine. There is no leak, or water flowing through the meter.

Go for the check valve(s)

I was glad to read this thread.  I just noticed this problem on my open loop setup with a watersoftener with the same Clack WS-1 valve (it was reading 0.3 gpm).  I have the Franklin Electric variable speed, contstant pressure system so I'm guessing that might not be a solution for you.  I think its more how the water softener and geo unit are piped... how close, etc... 

I'm going to make a note to install a check valve when I get a chance!

Put the expansion tank on the cold side of the water heater. Where I live we need regulators and check valves on every thing, to help control high pressure surges from water company. If you install the expansion tank it will extend the life of your water heater, maybe double or triple it. Most all regulators have built in check valves if you block the pressure you need to control it. They are often $100.00 or less on Ebay. J Miley Lived not your usual life