EVCO S.p.A.
EV3 HRV & EVD HRV
| Application manual ver. 1.0a | Code 1443DHRVE104
page 36 of 74
7
SELECTING THE OPERATING MODES
The controller always makes it possible to manage heating and cooling and use either “manual” operation or “time bands” to meet the
user’s needs in the best way.
7.1
Selecting the heating/cooling mode
There are three possibilities for selecting the operating mode:
- By digital input
- By probe (automatic)
- By keypad/supervisor.
If a digital input is configured as
‘Change of operating mode’
then it is the status of this input that determines the operating mode.
If a digital input is not configured but the automatic changeover function (C11=2) is active, the machine heats up if the probe
temperature configured by parameter C23 is lower than C25, while it cools down if this temperature is above C26. Parameter C24
defines the time required for the operating mode to switch.
If the changerover probe (C23) is not configured by the relative parameters (I01-I20) the configuration alarm is activated, if however,
the probe is in alarm mode the relative probe alarm is activated. In both cases this inhibits the automatic change of operating mode
and the machine remains in its “current” operating mode.
If the change of operating mode by digital input or automatic is active (based on the value of one of the probes provided) any
attempt to change the mode from the keypad will fail and there will be no warning of the reason for the failure of the action.
If a specific digital input is not configured and the automatic changeover function (C11=0) is not active, the operating mode is set
through the keypad and each time the DOWN key is held down, the operating mode will change ...-> COOL -> HEAT.
In this situation the supervisor is able to force the operating mode (S17 status).
When C11=1 ( Auto) the machine can be set to operate in heating or cooling mode or even automatically through the keypad
and by the supervisor. Each long press of the DOWN key changes the operating mode in the sequence ...-> COOL -> HEAT
→
AUTO.
7.2
Selecting the time band mode
The setpoints for temperature, for opening the mixing chamber damper and for the fan speed are set based on parameter
t01
and the
current time. The “temporary” setpoints for temperature, fan speed and mixing chamber damper regulation (if present) can be changed
from the keypad or by the supervisor in the following way:
- From the keypad by pressing the SET key and changing the values tMP, FAn, dMP
- By the supervisor by changing the status of S05 (fan speed), S09 (damper opening) and S19 (temperature).
In manual mode any change to these values is also reflected in the parameters, thus becoming final.
If the time bands are active, when a new band starts up or if the mode is changed from manual to time band or vice versa, the
setpoints are reassigned according to the parameters set.
7.2.1
Manual mode (t01 = 0)
Listed below are the setpoints used:
P07 manual temperature setpoint heating mode
P08 manual temperature setpoint cooling mode
P12 manual fan setpoint
P17 manual mixing chamber damper setpoint
7.2.2
Time band mode (t01 = 1)
The active time band is based on the current time scrolling back in time until a valid value is found in the parameters for the time
bands. If no valid mode is found (e.g. if the time band parameters t02-t32 have not been correctly set) the machine operates in manual
mode.
Each day of the week can be associated with a different day type (t26-t32).
Three “day types” (A, B, C) are available each of which can have up to 4 different time bands (t02-t25).
Each band depends on the active mode, the start time and the required comfort level.
The following comfort levels are available:
- Comfort (COM) for this mode the setpoints used are provided by the following parameters:
- P01 comfort temperature setpoint heating mode (winter)
- P02 comfort temperature setpoint cooling mode (summer)
- P09 comfort fan speed setpoint
- P14 comfort mixing chamber damper setpoint
