Ro Unit Check Value, Contamination, Water By Laws

[lgarvey]

Hey,

I got an RO unit today from RO man and have asked two plumbers to fit it. Both said they thought that it would need a check valve to be legal, so that contaminates are not going back into the water.

One plumber came out and installed the initial line, as a bit of a favour but didn't want to leave a receipt in case it needed a check valve.

Any ideas if a valve is needed as the documentation does not state whether it is built into the unit or not?

L

 

[OldMan47]

It does not need a check valve to function properly. Whether there are regulations about back flow preventers in your locality will be a question of local code of some kind. A back flow preventer is basically 2 check valves in a row that open a drain between the valves when the flow tries to reverse. In many tank type applications here, they are required to keep industrial uses from contaminating the public water supply. Where I live they are not required for a domestic RO but anybody outside Manchester who tries to answer this may be wrong on the legal front.