On 08/03/2019 12:24, AnthonyL wrote:
I've been trying to understand what happens with the hot water when my
wife screams that it has gone cold in the shower so I watched it the
other day.

Turn shower on, burner comes on, led lights (Baxi 105HE) start to
light up to a maximum. Everything fine for a few minutes then the
burner turns off, leds go back, and wife screams. Burner comes back
on - repeat and rinse.

Shouldn't the burner flame just adjust to maintain the temperature
rather than cut-out? Obvious behaviour of the CH but not for DHW.

Otherwise is this indicative of a thermistor problem with hysterisis
or similar? Is it easy to replace?


Has it always done this? As a mere user of the Baxi 105HE, not an
engineer thereof, I'm wondering where the CH & Hot Water temperature
knobs are set? Mine are set so the temperature never quite goes up to 70
(I was told to do this to reduce limescale deposits though I don't know
if that really works.) I never have any thermal cutout problems.

Hope this helps,

Nick