"Tom" wrote in message
...

Thanks Andy, would you agree that the Alpha might induce condensing
conditions in my standard boiler, assuming that thermostats and TRV are
susceptible to frequent adjustments in my household :-(

As long at the boiler is set to 80C this is highly unlikely when the system
is warmed up.

You may require a minimum flow through the boiler. Then I would forget the
Alpha a go for am open rad and room stat.