On Thursday, 5 November 2015 20:19:43 UTC, rick wrote:
On 05/11/2015 17:38, nt wrote:


In order to draw off hot water you need to run a de-stratification pump

I'm not seeing why. It's not normally how things work

I presume your pump is drawn the wrong way round on that pdf.

The baffle in the middle of the store for one reason.
The other reason I know of is that the DHW take off is from a crossflow
plate heat exchanger, to keep up continuous high flow rate of hot water,
then need to stir the tank or it quickly would form a cold 'pocket'
around itself and flow would cool down

I'm not seeing how any of that adds up. A crossflow PHE must be external, and will run hot from the top, returning it to the bottom. The pumping inherent in that prevents cold pockets. To get best boiler efficiency & provide a cooler zone for ufh the boiler hot should enter the top of the cylinder.


NT