No it should not affect how your system performs, but just one more thing to go wrong.Originally Posted by jgbfl
The check valve at the submersible doesn't stop the siphoning of water back down your well if you get a pin hole in the drop pipe, or if that check valve leaks..
Question, did you plumb into the bottom of your storage tank, or the top where it would never siphon the water back out?
What is a residential dual check valve (rdc)?
An rdc is similar to a DC (double check valve) in that it is a mechanical backflow preventer consisting of two independently acting, spring-loaded check valves. However, it usually does not include shutoff valves, may or may not be equipped with test cocks or ports, and is generally less reliable than a DC. An rdc is effective against backpressure backflow and backsiphonage but should be used to isolate only non-health hazards and is intended for use only in water service connections to single-family homes.
However if you have an air gap, i.e. filling from the top of the tank....
What is an air gap?
An air gap is a vertical, physical separation between the end of a water supply outlet and the flood-level rim of a receiving vessel. This separation must be at least twice the diameter of the water supply outlet and never less than one inch. An air gap is considered the maximum protection available against backpressure backflow or backsiphonage but is not always practical and can easily be bypassed.
Having said that, your inspector is the final athourity.