Mode Of Operation: Hot-Water Pre-Control - Honeywell SDC Service Manual

SDC / DHC
7.2.6
Function
EN2H-0221GE51 R0812
The boiler parallel shift of the tank loading pump (parameter) acts
on the mixed heating circuit demand.
The boiler parallel shift of mixed heating circuits acts on the heat
generator, provided the tank loading pump control mode has not
been set to "external storage tank".
The optional return flow limit acts on the flow mixture according to
the setting.
The hot-water pre-control acts only on hot-water loading
configured in the same device.

Mode of operation: Hot-water pre-control

When operating in combination with hot-water pre-control,
parameter 08 (tank drainage protection) does not act directly on
the heat generator, but on the hot-water pre-control.
Parameter 08 is always adjustable for function with pre-mixer.
Here, the "OFF" and "ON" settings have different effects, which
are described in the following.
With the setting "OFF", there will be no start-up protection through
the hot-water pre-control. The tank loading pump is switched on
without any delay.
With the setting "ON", the tank loading pump is switched on only
when the flow sensor detects that the hot-water setpoint
temperature + ½ switching difference hot water (without offset) is
reached:
=
HWPC
•
setpoin t
• SLP = ON if
HWPC
• SLP = OFF if
HWPC
+
WH P 09 HW (
setpoin t
1
≥ +
HW
actual setpoin t
≤
HW
actual setpoin t
Hydraulic Components
)
SD
HW
2
151