HVAC plant operating mode, for heat pump (HvacPltMod17)
Overview
The application function "HVAC plant operating mode 17, for fan coil unit, heat pump, radiant ceiling, radiator " (HvacPltMod17) selects the HVAC plant operating mode and considers the room operating mode, presence detection, HVAC presence mode and window contact. Warm-up and cool down request signals are received via the central operating mode AF.
Function
- The Plant operating mode (PltOpMod) can have the following states:
1:Off
2:Protection
3:Economy
4:Pre-Comfort
5:Comfort
6:Warm-up
7:Cool down
8:Room low temperature protection
9:Condensation overflow protection
10:Free cooling
11:Night cooling
12:Ventilation
13:Equipment temperature protection
14:Air volume flow off
15:Not used
16:Not used
17:Not used - The AF reads the room operating mode, presence detector, HVAC presence mode the window contact. Commands from central AFs are also received.
- The AF outputs the plant operating mode (PltOpMod), providing it to the room segments via a BACnet object, internal connection, and grouping.
- Switching delays can be configured to smooth plant mode switching (see Configuration).
Next room operating mode (NxROpMod)
To enhance energy efficiency, NxROpMod can be set to match the room operating mode expected to follow warm-up or cool down. A typical use case is a seldom used conference room that normally goes into Pre-Comfort after warm-up or cool down. Setting NxROpMod to Pre-Comfort would prevent the over-cooling or over-heating of the space by allowing Pre-Comfort setpoints to be used instead of Comfort setpoints during the warm-up or cool down phase.
The table shows the standard plant mode selection. No configurable selections are available.
IF | Then | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Room operating mode | Psc Det 1) | Hvac Psc Mod | Window contact | Vnt signal | NgtC signal | Cool down signal | Warmup signal | FreeC signal | Plant mode |
-- | -- | -- | Open | -- | -- | -- | -- | -- | Protection |
-- | Closed | True | -- | -- | -- | -- | Ventilation 2) | ||
Protection | -- | -- | Closed | False | -- | -- | -- | -- | Protection |
Economy | -- | -- | False | False | False | False | Economy | ||
True | False | False | False | Night cooling | |||||
-- | True | False | False | Cool down | |||||
-- | -- | True | False | Warm-up | |||||
-- | -- | -- | True | Free Cooling 3) | |||||
Pre-Comfort | -- | No Psc Fnct | -- | False | -- | False | Pre-Comfort | ||
-- | True | -- | False | Cool down | |||||
-- | -- | -- | True | Free Cooling 3) | |||||
Present | Cons. present & absent | -- | -- | -- | -- | Comfort | |||
Absent | Cons. present & absent | -- | False | -- | False | Pre-Comfort | |||
-- | True | -- | False | Cool down | |||||
-- | -- | -- | True | Free Cooling 3) | |||||
Comfort | -- | No Psc Fnct | -- | -- | -- | -- | Comfort | ||
Present | Cons. present & absent | -- | -- | -- | -- | Comfort | |||
Absent | Cons. present & absent | -- | False | -- | False | Pre-Comfort | |||
-- | True | -- | False | Cool down | |||||
-- | -- | -- | True | Free Cooling 3) | |||||
1) Presence detection with switch-on/off delay functionality, see Configuration.
2) Not supported by HvacPltMod17.
3) Only if in addition heating not active.
Configuration
Parameters
Description | Parameter | Default value |
|---|---|---|
Switch delay when present | SwiDlyPrst | 5 [min] |
Switch delay when absent | SwiDlyAbst | 5 [min] |
Interface
Interface | Description | Type | Ref. | Owned by |
|---|---|---|---|---|
PltOpMod | Plant operating mode 1:Off | MPrcVal | ● | - |
CoolDwnReq | Cool down request 0:Inactive | BCalcVal | ● | 1) |
WarmUpReq | Warm-up request 0:Inactive | BCalcVal | ● | 1) |
NgtCReq | Night cooling request 0:Inactive | BCalcVal | ● | 1) |
FreeCReq | FreeCReq 0:Inactive | BCalcVal | ● | 1) |
NxROpMod | Next room operating mode ▶ Can be set to match the room operating mode expected to follow warm-up or cool down, when that mode is not Comfort. 1:Protection | MPrcVal | ● | 1) |
CenEmgHvac | Central emergency for HVAC | GrpMbr | ● | - |
RCtl | Room control | GrpMaster | ◉ | Room |
1) Received from central AFs, provided here for monitoring.