Thanks Bob6464,
Tried to help you as much as I could without getting into too much trouble.
All of the solutions provided are freely available on the net.
My point was that you could have hot water for showering / bathing if you manually switched the gas valve at the boiler on and off at / for your convenience. PITA, but, you could at least have a hot shower and heating sporadically when required.
Apologies from me - and I don't speak for the forum, about the Knob - Knappers, who in his own right took it upon himself to have ago at me for trying to give you some help and sabotage your post.
I went slightly off track also, posting information freely available on the net.
Obviously some of the information, on your situation in particular, he has or had no knowledge of.
Sharing information - helping others..........I hope I gave you some assistance.
We're here to help each other, if I crossed some line, I haven't been informed as of yet......still waiting.
I haven't looked at Knapper's video he posted, if it had something to do with Plumbing I may have.
Did you? - Did it help your boiler issues?
Over and out,
Hope your new boiler gives you years of trouble free hot water & heating.
Oz