So WB believes it's back feeding and preventing boiler from going through sequence when a hot tap is opened? Has the customer actually confirmed this? Did he isolate supply to boiler, drop the dead leg of water out and then crack valve open a little while later to prove it's back feeding?
If that is the problem then yes anywhere where the hor and cold mix could be the problem ie the shower, especially if it's an old gravity shower. Install NRV's on hot and cold to shower will prevent this and further problems, although its probably best replace the shower now that its mains fed.
What's the incoming pressure to the property? I would consider a PRV on cold main where it enters the dwelling .
Also, you say you're experiencing back feeding (or at least boiler not igniting when a tap opens) but tell me the boiler is coming on to heat the store?
If that is the problem then yes anywhere where the hor and cold mix could be the problem ie the shower, especially if it's an old gravity shower. Install NRV's on hot and cold to shower will prevent this and further problems, although its probably best replace the shower now that its mains fed.
What's the incoming pressure to the property? I would consider a PRV on cold main where it enters the dwelling .
Also, you say you're experiencing back feeding (or at least boiler not igniting when a tap opens) but tell me the boiler is coming on to heat the store?
