Application

Room Segment Functions
Device Control Functions HVAC
62
Siemens Industry, Inc.
Application Note
A6V11692053
Smart Infrastructure – Building Products
2019-04-01
Hot Water Coil (HclHw11)
Application template: 14369
This application function operates a hot water valve for a heating coil. The main
output is an analog output for valve position.
Main features:
⚫ Hot water valve modulation
⚫ Heating available status
⚫ Interlocks
⚫ Supply chain interface
Function
The heating coil heating request (HclHReq) is received and processed into an
analog output signal for the heating coil valve position (HclVlvPos).
Basic function: Accept request signal from associated room controller and pass it
through a device mode logic switch; output the result as a command to the BACnet
object that controls the device.
Hot water valve modulation: In response to heating request from the room, the
heating valve is modulated to control the room temperature at setpoint. It can also
be 2-positioned in response to external trigger(s) for special modes such as
warmup or cool down, or safety conditions.
Configuration
Description
Parameter
Default value
Switch-on point for hot water demand
SwiOnPtHwDmd
4 [%]
Hysteresis for hot water demand
HysHwDmd
2 [%]
Switch-on point for air volume flow heating request
SwiOnAirFlHReq
4 [%]
Hysteresis for air volume flow heating request
HysAirFlHReq
2 [%]
Switch-on delay for air volume flow heating request
DlyOnAirFlHReq
30 [s]
Enable monitoring for air volume flow state
EnMonAirFlSta
0: No
Available Status
When the heating coil is available for heating, the binary output signal for Heating
coil available for heating (HclAvlH) will be "Yes" (available). HclAvlH is used by
the system to regulate heating resources. For example, if there is a call for heating
but the heating coil is not available because it is already at maximum capacity
(because device mode is fully open), then HclAvlH will signal "No" and the next
available heating resource in the temperature control sequence will be activated.
For heating available status to be "Yes", device mode must equal "Control mode"
(modulation).