ECKELMANN UA 400, Operating Instruction

Page: 39 / 401

Firmware V3.15 21.04.2021 39/401
5.5.4 Brine defrosting
Defrosting with brine may be considered a special form of discharge gas defrosting (hot gas defrosting). The
brine defrosting is initiated and ended via the CAN bus by the pack controller. A special feature of brine
defrosting consists in synchronized operation of the cooling relay and defrost relay, meaning that the cooling
relays remain open during defrosting.
Cooling relays and defrost relay are energized on initiation of brine defrosting. The display (Actual Values menu
on controller or in LDSWin) shows cooling to be off, as the cooling relays then assume a defrost function and
not a cooling function.
The defrost relays and cooling relays are de-energized separately by zones when defrost termination
temperature is obtained on the defrost sensors. Cooling does not resume until defrosting is terminated by the
pack controller via the CAN bus.
Fan controller - case controller
UA 111; UA 121; UR 41 NK (NT); UA 111 D: Fans are switched to continuous running during brine defrosting.
UR 141 TK (LT); UA 131 DD: Fans are switched off during brine defrosting.
Fan controller - cold-room controller
UR141 NK (NT) / UR 141 TK (LT): Heating circuit and second defrost stage are controlled as before in single-
zone operation. The second cooling relay remains off however during brine defrosting in single-zone operation
and does not simulate the second defrost stage.
Demand defrosting is ignored when brine defrosting is initiated. Any waiting time set is disregarded on
initiating brine defrosting. The defrost timer switches from INTERNAL to EXTERNAL when brine
defrosting is initiated.
