Filling loop connected

DocQuincy

Ruski wrote: »

Tuppence worth: there is a risk no matter how small that the check valve can fail and users can leave the valve open.
The only sure way to ensure complete non-contamination risk is to physically remove the connection, and that's why water regulations decree it.
Hth
Russ

Thanks. But wouldn't you need three failures (assuming you don't leave the valves open)? Both valves for the filling loop and the one-way valve?

missile

Ruski wrote: »

…. that's why water regulations decree it.

Can you post a link to this decree? …………. :money:

Alex1983

I think your worrying far too much about this, they are hardly ever disconnected but....the water regs are clear about removing the filling hose or at least 1 end to prevent backflow regardless of check valve.

Rodders53

missile wrote: »

Can you post a link to this decree? ………….

It's definitely good practice to disconnect, but rarely done ... https://www.wras.co.uk/consumers/resources/interpretations_and_advice/backflow_prevention/b54/

DocQuincy

Thanks everyon for your input. I know it is unlikely to cause problems. It's good to know all this all the same.

Rodders53 wrote: »

It's definitely good practice to disconnect, but rarely done ... https://www.wras.co.uk/consumers/resources/interpretations_and_advice/backflow_prevention/b54/

Your links says (bold mine):

Where a closed circuit (heating system etc) has been categorised by the water undertaker as a fluid category 3 risk the installation of a compliant double check valve on the fill point connection to the supply/distribution pipe may be considered as acceptable backflow protection.[/QUOTE]



Here's my boiler.


https://imgur.com/DXsgka9



Sorry I don't know the correct terminology but the pipe that goes into the left blue switch is one way. There is then a switch either side of the filling loop. Does this constitute “acceptable backflow protection” per the link?


I'm not worried now thanks to your reassurances. I was just curious as to how there could possibly ever be any backflow since three things would have to fail at once (presuming you don't leave the valves open)?