Backflow prevention

[ChrisCCCC]

Hello. Searched the forum, but couldn't find an answer.

My water well set up has an untreated hose bib for watering lawns before my water softener, and filters. When water is drawn from the untreated side, water backflows from my filters, softener, etc to pressurize the untreated system until my pump kicks in and charges the pressure tank. While my filters are backflowing, there is a lot of water hammering and air in the lines. If I manually close the filter valves this prevent the backflow and air. Do water softener normally have a backflow preventor build in, or could I just add a check valve right before my filters?

Would a sharkbite check valve work okay, or do you have other suggestions?

Thank you.

 

[Bannerman]

The well's pressure tank and pressure switch should be located directly after the well pump with the hose bib, water treatment equipment and house plumbing to follow. The pressure tank will store and supply water under pressure until the system pressure drops to the pressure switch cut-in pressure which will then activate the pump. With the pressure tank in the correct location, there should be no source of water after the water softener to cause reverse flow back through the softener to supply the outside hose bib.

From your description, it sounds like the pressure tank is located after the softener and filters.

 

[Sponsor]

 

[ChrisCCCC]

Thank you for the response. The pressure tank and pressure switch are located directly after the well pump. The untreated line for the hose bibs tee-off the main line. This main line then heads towards the house's treatment system.

The first stage in my treatment system is an iron oxidization filter that uses air to filter out the iron in my water. Could there be an issue with this filter and is allowing air into my untreated water line?

Thank you in advance.

 

[Valveman]

The air in your iron filter is working like a pressure tank and pushing water backwards. Yes adding a check valve after the pressure tank and tee to the irrigation should fix that. Shark bite is easy but may not be the longest lasting way to do this.

 

[Bannerman]

When you said filters, I did not anticipate an AIO system (air injection oxidation). An AIO system does require a check valve, but that will usually be builtin to the system. In adding a check valve, a thermal expansion tank on the inlet to the water heater will also be required as the cold water that expands when heated, will no longer be able to push backwards to be absorbed by the well pressure tank.

 

[ChrisCCCC]

Thank you for the feedback. Much appreciated. Do you have a recommendation regarding a check valve for this application?

 

[Valveman]

Brass or Stainless, spring loaded, poppet style.