Siemens RDG20 KN Series Basic Documentation page 72

Functions
4
Additional functions
2-pipe+ el. heat
2-pipe/2-stage
4-pipe
4-pipe+ el. heater
4-pipe/2-stage
4-pipe with 6-port ball valve
4-pipe with PICV + 6-port
valve as changeover
IAQ - CO control,
2
KNX objects
IAQ - CO control –damper
2
signal (P453, P454, P455,
P456)
72 | 180
✓
✓
✓
✓
✓
✓
Selectable via P351 (Fan speeds)
1)
Selectable via P453 (Indoor air quality damper)
2)
Universal (CLC) applications can be set by switching off the fan functions
3)
(P350 = 0)
Note for IAQ control on universal (CLC) heating and cooling systems.
Application can be set as per Applications for universal systems [➙ 44] and by
switching off the fan function (P350 = 0).
On those applications without fan control, when the IAQ setpoint P023 is exceeded,
the thermostat controls the position of the damper. An independent fresh air
system guarantees the fresh air flow in the room.
See the possible combinations of applications, control signals and types of the
damper in the table for RDG204KN and RDG264KN as above.
Frost protection function is not available for universal applications.
IAQ – CO S-Mode objects:
2
•
100 Built-in room air quality value (out)
•
101 External room air quality value (in, for M/S – manager/subordinate function)
•
102 DC damper demand (1-byte out)
•
103 On/Off damper demand (1-bit in)
The CO concentration is available on the bus via S-Mode object 100 "Built-in room
2
air quality value". This information can be used to share the CO
the rooms, to an independent fresh air controller.
The S-Mode object 102 "DC damper demand" and the object 103 "On/Off damper
demand" can be used to share the current position of the damper to 3
equipment.
When the thermostats use M/S - manager/subordinate function, the CO
concentration of the master can be received from the subordinate device via S-
Mode object 101 "external room air quality value".
IAQ - CO
control with DC damper: P453 = 1
2
If DC 0...10 V damper control is selected, the following parameters can be used:
•
P453: Indoor air quality damper (1 = DC 0...10 V (U1))
•
P454: IAQ damper proportional band Xp
•
P455: Minimum damper position
•
P353, P357: Fan min. output
The following graphics show DC damper position during heating/cooling demand
and in dead zone; the fan is switched on via IAQ demand.
•
On/Off + DC
•
✓ DC + On/Off
•
2 × DC
✓
•
3 × DC
•
✓ On/Off + 2
✓
•
4 × DC
•
DC
✓
•
On/Off + DC
✓
✓
× DC ✓
✓
✓
concentration in
2
rd
party
2
A6V11545892_en--_c
✓
✓
✓
✓