Dimplex Solar Series, Technical Manual

Page: 34 / 72

Technical manual
Page 34 of 72
ST0133 – A 02/09
SOLAR
EV
pc EV
pc mp
V
V V
p p
−
⋅ = [10]
Where: p
mp
[bar] membrane pressure
p
pc
[bar] cold fill pressure
V
EV
[l] expansion vessel volume
V
pc
[l] pre-charge volume
The expansion vessel membrane pressure p
mp
has to be adjusted before the system is
being filled and pressurised. Once the theoretical expansion vessel volume has been
calculated, the next larger available vessel is to be chosen.
A sizing guide of the expansion vessel under the stated conditions is given in Figure 34.
Please note that the calculation should be carried out in the case that the assumptions
shown in Figure 34 do not apply.
Figure 34 – Expansion vessel sizing chart applying Equations 5 to 10