Switch-Off Of District Heating Control - Honeywell SDC Service Manual

Hydraulic Components
7.2.11
Operation
Function
7.2.12
7.2.13
156

Switch-off of district heating control

"District Heating" menu, parameter 01: Setting range is extended
to OFF,
–10 ... +50.
Setting OFF means district heating is deactivated.
District heating valve permanently in STOP position when
deactivated.
The switch-over of the heat generator is controlled from the
"District Heating" menu, parameter 01.
Return interval flushing
If the return max. limit is active and the district heating valve is
opened less than 5%, the district heating valve is opened to 10%
every 10 minutes for heat demand, so as to obtain an adequately
precise return temperature measurement. This assures that the
limit sensor is adequately supplied in the return.
Heat meter for additional limitation according to the volume
flow or thermal output
The requirement for this function is the heat meter, whose
information (pulse per volume or pulse per thermal output) is
called upon for this limit. Calibration of the thermal output and the
volume flow with parameters 12 and 13 allows calculating the
entities thermal output and volume flow. These values are

displayed with the
volume flow are entered under parameters 14 and 15.
This limitation function operates as PI controller above the
setpoint value, using the same parameters as the temperature
control function.
The values are independent of the outside temperature. The heat
flow is derived from a volume signal in the following way:
key. Setpoint limits for thermal output and
SDC / DHC
EN2H-0221GE51 R0812