Andy Hall wrote:

What flow rate? There was a recent thread here indicating that at
least 25-30lpm is needed for such a shower. This is easily
achievable with a storage system.

The mid range Rinnai, at 54kW is using almost the entire throughput of
a standard domestic gas supply and still manages less than 20lpm, and
that is at a 33 degree rather than the standard 35 degree temperature
rise. Specifications on some models are for only a 25 degree rise.

It would take the 70kW one and a commercial gas supply to achieve the
flow rate needed for a proper body jet shower.

Efficiency is quite poor. The 69kW input model has an output to
water of only 55.4kW - around 80%. This would not be allowed for a
normal boiler.

You are just letting facts get in the way of the argument. :-)

Dribble has already been told many times how the Japs are moving to
copper tank storage in their droves but he still can't accept he is
wrong.

--
Matt (aka Dribble's nemesis)

The future's bright, the future's copper
Dump that combi today and keep the Dr away