This is to prevent non potable water from flowing backwards possibly mixing and contaminating potable drinking water.
Water softener drain line check valve.
This valve closes when the brine level in the tank drops at the end of a regen cycle to preven drawing air into the water softener itself.
If there is a blockage then you have to remove it.
A professional will need to clean or replace an injector.
Moreover check the brine line and the valve.
Blocked drain hose water softener is not draining.
By code water softeners must be emptied into a laundry sink floor drain sump hole or properly trapped special outlet preserving an air gap of at.
Get expert help with your water softener maintenance.
On water softener service calls in minnesota we find a wide variety of drain line material being used.
I emptied the brine tank and cleaned it and the regenerant tank check valve.
The over flo line could go to the same place as the heater relief output.
The line from the control valve will have a significant pressure while the softener is in recharge or backwash modes and should be hard plumbed through a check.
One over flo from the brine tank and one off the control valve.
The industry standard is a polypropylene drain line that is rigid yet flexible.
Many water softener models use a check valve at the top or at the bottom of a brine pick up tube in the brine tank.
There are two drain lines from a water softener.
Water softener air check valve troubleshooting.
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The injector could also be obstructed possibly with particles or debris.
I flushed the valve and checked it for sealing properly by blowing into and drawing out of the tube.
Check the drain line for any kinks or clogs.