The current planned configuration is:
Pool and spillover spa share a filter and a heater.
Spa is an Imperial WhiteWave spa. This spa has one pipe in and one pipe out.
I'm not impressed with the Hayward ProLogic system.
The PB said that there would be basically two modes:
1. Pool Mode: Filtration where the 3-way valve on both the drains and returns allow a little bit of flow to/from the spa. A bit more from the return so that the spa does spillover to get rid of surface debris. A bit from the drains in the spa to get rid of any dirt on the spa floor.
2. Spa Mode: Water from heater goes to/from only the spa.
The PB claims the position of the 3-way must be precise (so as not to drain the spa). This necessitates the use of actuators and that necessitates the use of a control system.
Problem: I don't want a control system.
I found the Pentair FullFloFX valve. It has stop pins, would they work? I don't think the valve needs to be "super precise". I can have much more flow in the return than the drain because the extra water will spillover. This is not a problem. The problem is the potential for draining the spa.
I'm looking for a way to turn a 3-way valve so that I can completely close the branch to the pool (normal operation), but I cannot completely close the branch to the spa.
Or....Is there another way to solve this problem with the constraint that the filter and heater are shared?