Control Of Apartment Building Substations With Domestic Hot Water - Honeywell AUTOMATIC CONTROL Engineering Manual

Reference
DDC Controller
TI 01 Outdoor air temperature
TI 31 Room temperature sensor &
setpoint setting
TIC 12 PRF temperature
TIC 22 SSF temperature
Control Strategies:
1. Primary temperatures: supply up to 265F, return up to 195F.
2. Secondary temperatures: supply up to 195F, return up
to 160F.
3. System provides a SSF temperature depending on the
outdoor temperature according to a reset schedule
(Fig. 139).
4. Heat demand dependent pump switching, with one full
cycle of the pump per day to prevent seizing.
5. Diagnostic functions via connector.
6. PRF temperature limitation with fixed and variable value
available. The control valve reduces the flow until the
PRF temperature is below the parameter value. The
setpoint can be fixed or floating with a certain ∆T below
the PSF.
7. SSF temperature limitation available (parameter).

CONTROL OF APARTMENT BUILDING SUBSTATIONS WITH DOMESTIC HOT WATER

DDC Control of Two-Stage Heat Exchanger for Heating and Domestic Hot Water.
Reference
DDC Controller
PI 11 PSF pressure
PI 17 PRF Pressure
PI 22 DHW pressure (supply flow)
PI 24 DHW pressure (return flow)
PI 28 Cold water pressure
PI 213 DHW network pressure
PIC 32 SSF pressure
PIC 35 SRF pressure
QIR 02 Elec. Power metering
QIR 15 Heat metering
QIR 214 Drinking water metering
TI 01 Outdoor air temperature
TI 12 PSF temperature
TI 215 DHW circulation, return flow temperature
CHILLER, BOILER, AND DISTRIBUTION SYSTEM CONTROL APPLICATIONS
Table 11. Description of Figure 138 Reference Points.
Description
Table 12. Description of Figure 140 Controls.
Description
Reference
TIC 24 SRF temperature
TZA+ 21 Safety temperature limit (SSF)
Y 11 Control valve PRF
Y 23 Circulating pump
270
255
240
235
220
205
190
175
160
-5
OUTSIDE AIR TEMPERATURE (°F)
Fig. 139. SSF Temperature Reset Schedule.
Reference
TIC 16 PRF–temperature
TIC 21 DHW temperature (supply flow)
TIC 31 SSF temperature
TIC 34 SRF temperature
Y 13 Actuator valve (SSF temperature control)
Y 14 Actuator valve (DHW temperature control)
Y 23 Actuator valve (DHW supply flow)
Y 25, 26, 27 DHW circulating pumps
Y 29, 210 DHW pressure booster pumps
Y 31 Actuator valve (SSF)
Y 36, 37 Circulating pumps (secondary fl.)
Y 38, 39 Refill pumps (PRF to SRF)
Y 211, 212 DHW pressure booster pumps
Y 310 Actuator valve
393 ENGINEERING MANUAL OF AUTOMATIC CONTROL
Description
65
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M10673
Description