Initial Pull Down; Automatic Pull Down (Applicable For Eeta Only) - Danfoss EET Series User Manual

Refrigeration controller, type EET series
Figure 5: Advanced Fan control
Fan ON cycle
Fan stop cycle
Fan start delay Fan stop delay

Initial pull down

If the cabinet temperature is very high at power up, the controller detects the need for faster cooling and enters into
Initial pull down mode. In this mode, the controller adjusts the defrost interval by skipping it to a later time than its
scheduled intervals until the desired cabinet temperature is achieved.
Figure 6: Initial pull down
Without initial pull down, where defrost is initiated
Cut-in
Cut-out
This ensures faster cooling by achieving the required cabinet temperature in the shortest period possible.

Automatic Pull down (applicable for EETa only)

This feature helps to achieve faster and extra cooling when there is an increase in the cabinet temperature due to
frequent door opening or fresh food products being placed in the cabinet. The faster and extra cooling is achieved
by adjusting the temperature set point and defrost intervals until the desired setpoint range is achieved. The
controller detects this mode by monitoring the cabinet temperature behaviour, also it is possible to trigger this
mode manually via a digital input switch.
Figure 7: Pull down/Super cool mode
Cut-in
Set point
Cut-out
> 1 hr
(pull down initiated, when the cabinet
temp is above pit for for more than 1 hr)
© Danfoss | Climate Solutions | 2023.07
Compressor cut in
Cabinet Air
Compressor cut out
Fan
Compressor
With initial pull down
Initial pull down initiation (Pit)
Defrost terminate temp
0 ºC
Time saving, with 'Initial pull down'
∆ t
feature enabled
Pull Down Initiation (Pit)
Pull down offset temp (Pit)
Pdd
(pull down duration)
BC320944106159en-000301 | 7