Emerson Dixell IEV22D Manual page 24

7.1.1 Manual mode
If manual mode has been selected (par. Et2/Et5), the controller will bring the valve to the number of
steps set in parameter Et3/Et6 while remaining in that position; opening and/or closing valve are not
active.
This can be helpful during the set-up of the machine or in case of maintenance.
7.1.2 Adjustment mode
Only at start-up, regardless of the mode of operation, the valve will be completely closed by reaching
the maximum number of steps of the Ec13/Ec22 valve plus the extra steps for the complete closure
Ec11/Ec20.
Once it is closed completely, it will go to the adjustment position by performing the relaxation steps
Ec12/Ec21 while opening.
When the driver valve starts to regulate the valve moves to the number of steps set by Et1 / Et4 and
remains there for the time Et23 / Et43.
PID parameters for summer and winter operation mode must be configured by the user and adapted in
function of the type of machine and plant.
7.1.3 Defrost
The adjustment in defrost mode is carried out like the adjustment in cooling mode, but the proportional
constant is determined by the specific Et51 parameter.
In the event of a circuit with two valves, one configured to only operate in heat pump mode and one
configured only operate in chiller mode, defrost is carried out with the valve configured for the chiller
mode.
In the event of a circuit with just one valve that operates in chiller and heat pump mode, the valve will
also carry out the defrost.
If the valve(s) are set for operation in heat pump mode only, the defrost valves will not be activated.
Valve connected via LAN to Ichill – EVO series
•
Defrost input
o
o
1592026260 IEV22-24D GB r.1.0 21.02.2019
Ichill turns off the compressor(s) before reversing the gas cycle
when Ichill turns off circuit's compressors to perform the defrost, the
▪
valve closes.
when Ichill requests the switch-on of the compressors after reversing
▪
the gas cycle to perform the defrost. The valve opens at the step
number set under parameter Et52 / Et54 and maintains this position for
the time set under Et53 / Et55 before providing the consent to Ichill to
turn on the compressor(s) for the defrost stage
after the Et53 / Et55 pre-aperture time, the valve provides adjustments
▪
according to the chiller mode, though the proportional component is
provided by the specific Et51 defrost parameter
Ichill does not turn off the compressor(s) before reversing the gas cycle
when Ichill transmits the defrost status to the valve (i.e. when it
▪
reverses the gas cycle), the valve starts adjusting according to the
chiller mode, though the proportional component is provided by the
specific Et51 defrost parameter
IEV 24/60