Carel uChiller UCHBD00001230, User Manual

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80
ENG
μc0300053EN rel. 2.2 - 14.12.2021
Functions
5.20.2 Heater management on air-air units
This function is only active when the unit is on - main fan on and control active or in defrost.
The type of control is set using parameter F028:
• room temperature (F028 = 0)
• air supply temperature (F028 = 1)
The user can set two diff erent off sets, one in cooling mode and one in heating mode.
The off set is a value that is subtracted from the current set point in cooling mode, or added to the current set point in heating
mode. A diff erential can also be set to defi ne the activation/deactivation temperature of the two heater steps.
Electric heaters can be activated during defrosting. If this function is activated by the user, the heaters remain on for the entire
duration of the defrost, including the dripping and post-dripping phases.
Operation of the electric heaters follows the scheme shown below.
300053_073_R01
Diff Diff Offset
SetA
R1
R 2
Fig. 5.ae
User
C
ode Description Def Min Max U
O
M
M F012 Off set on set point in cooling mode for the heaters 1.0 0.0 99.9 °K
M F013 Diff erential on set point in cooling mode for the heaters 0.5 0.2 99.9 °K
M F014 Off set on set point in heating mode for the heaters 3.0 0.0 99.9 °K
M F015 Diff erential on set point in heating mode for the heaters 1.0 0.2 99.9 °K
M F016 Heaters active during defrost (0= No, 1=Yes) 0 0 1 -
M F028 Air heating: probe for user heater temperature control
0 = ROOM
1 = SUPPLY 0 0 1 -
5.21 Automatic heater management for water units (Legacy model only)
The uChiller Legacy version can manage auxiliary heaters as part of the main control, even on air/water and water/water units.
The function is active
• only when the unit is on
• with the fan/pump on
• only in heating mode
• when control is active
The heater control diagram is the same as shown in par. 5.20.2 for air/air units.
The control set point (SetH) and probe are the same used for the main control.
An off set (F014) and diff erential (F015) can be set to defi ne the auxiliary heater activation/deactivation limits.
Example: The following fi gure shows the control diagram with one auxiliary heater only.
300053_203_R01
Power
request
100%
0%
SetR - SetA - Off - Diff BP SetA T
Off (F014)
Diff (F015) Diff (F015)
Fig. 5.af