EWWQ090G ÷ EWWQ720L - R410A - Water-cooled scroll chillers
EWLQ090G ÷ EWLQ720L - R410A - Condenser less
EWHQ100G ÷ EWHQ400G - R410A - Heat pump scroll chillers
EWAQ-G 075
- R410A - Air-cooled scroll chillers
EWAQ-
- R410A - Air-cooled scroll chillers
EWYQ-
- R410A - Air-cooled scroll heat pumps
Air and Water cooled scroll chillers & heat pump
Operation
Manual
Operation Manual
54
EWWQ - EWLQ - EWHQ
EWAQ - EWYQ
Air or Water cooled scroll chiller &
heat pump
D-EOMHW00107-15EN
The heater contact has to be connected to an external backup heater inserted into the buffer tank
of the customer’s water system.
There are several conditions that can enable the heater contact:
When the unit runs at low ambient temperature it may not be able to satisfy the Heat
Setpoint. In this case if all of the following are TRUE:
o
the OAT is lower than the Backup Heater enable temperature,
o
the unit is running at full capacity,
o
the Leaving Water Temperature is lower than the Heat Setpoint
– Stage Up dT,
If unit is in defrost,
If there is an alarm active AND the Leaving Water Temperature is lower than the Heat
Setpoint
– Stage Up dT,
To activate the Backup Heater no Capacity Limitation must be active.
The Backup Heater is then deactivated if any of the following is TRUE:
the Leaving Water Temperature rises above the Heat Setpoint,
the Unit Mode is different from Heat,
A Capacity Limitation become active.
5.6 Condensation Control (W/C only)
The UC provides the possibility to choose between three different types of condensing control:
1. Pressure
2. Cond In
3. Cond Out
Depending on the unit type (Chiller, Condenser less, Heat pump with water inversion, Heat pump
with gas inversion) only some of the previous condensing controls are available.
5.6.1 Pressure (W/C only)
Pressure control is available for the following unit type:
-
Chiller
-
Condenser-less
In this control mode the controller regulates the condensing saturated temperature (quantity
directly connected to the condensing pressure). From the menu Circ x Cond Control 4.3.1.2 is
possible set condensing saturated temperature setpoint and the maximum and minimum output of
the regulation signal.
When this condensing control mode is active the controller provides two 0-10V signals (one per
circuit) that can be used to control one/two remote condensers (in case of condenser-less unit) or
one/two water valves (in case of chiller).
The controller also provides two digital contact (one per circuit) that can be used to enable the
remote condensers or the condensing pumps.
