Table of Contents
Advertisement
Setting 2
Example
Setting 3
68/126
Siemens Building Technologies
HVAC Products
A temporary drop of the d.h.w. flow temperature is accepted. Heat losses are only par-
tially compensated for; the flow temperature may drop by a maximum of 20 %. Subse-
quent heating up to the d.h.w. setpoint always takes a minimum of 5 minutes.
For the compensation of heat losses, the circulating pump must be released. If it is not
released, no control is provided independent of the d.h.w. flow temperature.
D.h.w. setpoint T
= 50 °C
BWw
Cold water temperature T
∆
Permissible reduction
T = 20 %
Minimum d.h.w. flow temperature T
∆
T
= T
–
T × (T
BWV
BWw
BWw
The aim is to maintain the d.h.w. setpoint and all heat losses will be fully compensated
for. A circulating pump is used.
16.3.7 Cold water sensor
Cold water sensor B32 is fitted after the mixing point of cold water return and circulation
return. It should be located as close as possible to the mixing point. The sensor detects
temperature changes on the cold water side, which are then included in the flow tem-
perature control. This improves the control performance considerably.
Basic documentation RVD240
16 D.h.w. heating
= 10 °C (fixed value):
Nx
= ?
BWV
– T
) = 50 – 0.2 (50 – 10) = 42 °C
Nx
CE1P2384en
27.05.2004
Advertisement
Table of Contents
