David Williams wrote:
Thanks, I'll try that tomorrow. As I mentioned above, the water
pressure to the unit is fine... on the 'cold' setting (i.e. basically
just run through from mains) it pumps around 8.5-9 l/min.

David we have the same model, and when it was installed had a problem with
it, as the unit is about 2 yrs ago I can't quite remember what it was but
had a problem of booting up and giving the low pressure warning and the
water was only luke warm, the triton guy knew exactly what it was straight
away and replaced the circuit board in the control panel (on/off panel
part - he said it was good job it was on the control panel as apparently the
heater box was inaccessible at least for him where the plumber had put it -
anyway another story) - all this is slightly irrelevant really I guess, but
one thing that I did note was the flow rates - apparently our water pressure
is only just enough and we found that when we had the filter bit between the
water intel pipe and the unit sometimes the low flow rate light came on, and
wouldn't work - so we took out the filter bit (I know you shouldn't - but it
worked for us!), but from memory with the filter in and on full cold on we
were getting something like 15 litres / min (I can check this a weekend with
filter off - if you wanted), so its just occurred to me that although your
pressure is okay I wonder if your flow rate is okay - the manual says it
needs a min of 9 lit / min!!

Jon