On Wed, 26 Sep 2018 10:11:00 +1000, 543dsa, better known as cantankerous
trolling senile geezer Rot Speed, wrote:


OK, let's try:

Hot water cylinder 450mm dia, 1.2m tall (first one on Screwfix)
pi*d*l = 3.14*0.45*1.2 = 1.7 sqm

According to the calculator, a 'wall' with 60C inside and 20C outside:

Uninsulated (1mm of steel): U=5.55 W/m^2 K
+25mm of polyurethane: U=0.85
+80mm of glassfib U=0.31

deltaT = 60-20 = 40
Uninsulated, power transfer ('loss') = 1.7*5.55*40 = 377W = 3306 kWh/year
+25mm PU = 1.7*0.85*40 = 57.8W = 506 kWh/year
+80mm GF = 1.7*0.31*40 = 21.1W = 185 kWh/year

The problem is getting a real figure for the added insulation.
That number is plucked out of the air, its not the real figure.

LOL Senile Rot knows it BETTER ...AGAIN!

--
Richard addressing Rot Speed:
"**** you're thick/pathetic excuse for a troll."
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