Thursday 21st February 2008.
I forgot to mention the food arrived on Tuesday. I don't know how I forgot, I spent most of the afternoon moving it bag by bag into the container! A little over 2 tons of food, so plenty for the Open Weekend.
As I mentioned yesterday, today I started doing some re-plumbing. The returns from the static Kaldnes filters on the first 4 concrete ponds I built were sent up and over the showers. Although this is good for the showers, as it increase the flow rate, the head loss on the Aquamax pumps is just too great to get an efficient turnover. Along with this, the heat exchangers on these 4 ponds were added after the ponds were finished and put on in a rush during the first winter. They have been fed by submersible pumps and this is very inefficient use of power, so the new plumbing will be from static Kaldnes bays to UV to heat exchanger and then return the water over the side of the pond.
I only managed to get one done today, but it has worked a treat and the flow rate has increased quite considerably.
A point I may have raised before (I meant to, but not sure if I did??, getting old !!!) concerns the heat exchangers. In the situation above it is a worst case scenario, in that the water is pumped unfiltered through the heat exchangers, but the photo below shows just how the restriction with the exchanger and the heat just seem to attract the waste.
As they start to block, the heat transfer to the water becomes less, the heat can be felt on the outside of the exchanger and the pond ends up always calling for heat, yet never quite getting there.
This heat exchanger was cleaned only a couple of months ago.