ECKELMANN UA 400 - Defrost in General

Firmware V3.15
21.04.2021
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5.5.2 Defrost in general
Defrosting prevents icing of the evaporators due to normal control action. Defrosting is performed by
supplementary heating of the evaporator by the off-cycle method. Refrigeration point temperature control is
deactivatedduringdefrosting.Defrostingdiffersforsingle-zoneandtwo-zoneoperation.
Defrosting in single-zone operation
R1.x: Evaporator sensor (with UA 121, UA 131, UR 141 NK/TK, UA 131 DD these sensors are used for
defrosting)
R2.x:Supplyairsensor(withUA111,UA111D,UA141)thesesensorsareusedfordefrosting)
Solenoidvalve1:RelayforSolenoidValve1
Defrost heater 1 to 4: Relay for Defrost Heater 1 to 4 (depending on controller type)
Allocation of sensors to defrost relays
Optional,non-connectedsensorsarenotusedforoperationofthedefrostrelays.
Controller type Required sensors Allocated defrost relay
UA 111 / UA 111 D / UA 141 R2.1 R2.2 R2.3 R2.4 (R2.5 with UA 111 D only) Defrost relay 1
– Defrost relay 2
UA 121 R1.1 R1.2 R1.3 R1.4 Defrost relay 1
– Defrost relay 2
UA 131 / UA 131 DD R1.1 Defrost relay 1
R1.2 Defrost relay 2
R1.3 Defrost relay 3
R1.4 Defrost relay 4
UR 141 NK(NT) / UR 141 TK(LT) R1.1 R1.2 Defrost relay 1
R1.3 R1.4 Defrost relay 2