Carel kVent, Manual

Page: 21 / 53

kVent – rel 3.1 – 22/06/2018
21
5. FUNCTIONS
5.1 Input functions
Here below the list of analog inputs functions:
AI Code Analog input Function
1 Ga01 Supply temperature Main temperature regulation
2 Ga06 Return temperature
Supply setpoint compensation
Fire alarm activation
3 Ga11 External temperature
Recovery control and defrost
FreeCooling/freeheating
Cool/Heat mode changeover
Antifreeze and antifrost control
Fast heating function
4 Ga16 Exhaust temperature
Fire alarm in case of return probe
broken
6 Ga26 Back water temperature Antifreeze control
10 Ga 46
Preheater back water
temperature
Antifreeze control
11 Ga51
After preheater
temperature Main preheating regulation
Recovery defrost
12 Ga56 CO2 sensor Fresh air regulation
13 Ga61 Supply air pressure VAV and CAV regulation
14 Ga66 Exhaust air pressure VAV and CAV regulation
15 Ga 71 Supply humidity Main humidity regulation
24 GaB6 VOC sensor Fresh air regulation
25 GaC1 Fresh air humidity Freecoling/freeheating enabling
Here below the list of digital inputs functions:
DI Code Digital input Function
1 Gb01 Fire alarm Fire alarm activation
2 Gb03 Fan overload Stop unit
3 Gb05 Humidifier alarm Stop humidifier
4 Gb07 Remote On Start/Stop the unit with timings
5 Gb09 Summer/Winter Define working mode
6 Gb11 Cooling alarm Stop cooling
8
Gb15 Freeze alarm Stop ventilation
Force heating valve at 100%
9 Gb17 Heating alarm Stop unit and force ventilation ON
10 Gb19 Eco Force unit in Economy mode
11 Gb21 Precomfort Force unit in Precomfort mode
12 Gb23 Comfort Force unit in Comfort mode
13 Gb25 Supply filter alarm Warning dirty filter
14 Gb27 Supply filter alarm 2 Warning dirty filter
15 Gb29 Return filter alarm Warning dirty filter
21 Gb41 Supply air flow switch Check air flow and stop unit
22 Gb43 Return air flow switch Check air flow and stop unit
23 Gb45 Recovery clogged Recovery in defrost mode
24 Gb47 Door Switch Door open
5.2 On request
The On status requires the AND logic of:
•
Unit configured by Service (I003)
•
No serious alarm
•
On by digital input
•
On by the OR of the following conditions:
o
On by pGD (X00a)
o
On by BMS
o
On by thTune, if present
o
On by scheduler, if enabled
Variable mode is shared with all the control sources.
If any condition go to OFF, the unit will turn OFF.
5.3 Cooling/Heating changeover
The external and room/return temperatures are considered: if
the external temperature is lower than a minimum threshold or
greater than a upper threshold the heating or cooling mode
can be forced:
In the middle, between the heating and cooling external
temperature thresholds, or when the external temperature
probe isn’t available the heating or cooling mode will be
decided considering the room temperature or the return
temperature (if the probes are available), here below it is
represented the behaviour in case of room temperature:
If the room temperature is greater than the setpoint, the unit
starts in cooling mode and remains in cooling mode until the
room temperature becomes lower than the setpoint for a
settable delay (H013), then the heating mode is activated. In
the same way, if the starting temperature is lower than the
setpoint the unit starts in heating mode and remains in heating
mode until the room temperature becomes greater than the
setpoint for the same delay.
5.4 Temperature regulation strategy
Compensation 5.4.1
The regulation of the unit could be done according the return,
supply or room set.
In case of return or room regulation, kVent provides the
compensation control strategy, based on return or room and
external temperature. Compensation modulate the supply
setpoint between the minimum and maximum supply setpoint.
Final supply setpoint is calculated as following:
%
%
%
-100% is equal to maximum supply setpoint and 100% is equal
to minimum supply setpoint, as in the following graph:
External temp.
Cooling
Heating
Based on room temp.
H011 H012
Supply temp.
Cooling
Heating
Delay Delay
Supply setpoint
2.0°C 2.0°C
0
Max cool
H010
External temperature compensation
100
-100
Min cool
H009
Min heat
H007
Max heat
H008
Return temperature compensation
Return set
100
0
-100
PID regulation
H005
H006
Min set
H002
Max set
H001
-100% 100%
Supply
set