Daikin EWAQ-G, Руководство по эксплуатации

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EWWQ090G ÷ EWWQ720L - R410A - Water-cooled scroll chillers
EWLQ090G ÷ EWLQ720L - R410A - Condenser less
EWHQ100G ÷ EWHQ400G - R410A - Heat pump scroll chillers
EWAQ-
- 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
EWWQ - EWLQ - EWHQ
EWAQ - EWYQ
Air or Water cooled scroll chiller &
heat pump
D-EOMHW00107-15EN
Operation Manual
45
Compressors are always started and stopped to guarantee the balancing of running hours and
number or starts in multiple circuits units. This strategy optimizes the lifetime of compressors,
inverters, capacitors and all the others circuit components.
5.1.5 Alarm Settings
Factory defaults are set for standard cooling mode, therefore they may not be properly tuned when
working at different conditions. Depending on the application, the following alarm limits need to be
adjusted:

Low Press Hold

Low Press Unload

Evap Water Frz

Cond Water Frz (W/C only)
Low Press Hold Set the minimum refrigerant pressure of the unit. It is generally recommended to set to a value whose saturated
temperature is 8 to 10°C below the minimum active setpoint. This will allow a safe operation and a proper control
of compressor suction superheat.
Low Press Unload Set lower than the hold threshold enough to allow a suction pressure recovery from fast transients without
unloading the compressor. A 20 kPa differential is generally appropriate for most applications.
Evap Water Frz Stops the unit in case the evaporator leaving temperature falls below a given threshold. To allow a safe operation
of the chiller, this setting must be adequate to the minimum temperature allowed by the mixture water/glycol
present in the evaporator water circuit.
Cond Water Frz
(W/C only) Stops the unit in case the condenser leaving temperature falls below a given threshold. To allow a safe operation
of the chiller, this setting must be adequate to the minimum temperature allowed by the mixture water/glycol
present in the condenser water circuit.
S
P
SP
+StageUpΔT
SP
+StartUpΔT
ELWT [°C]
First
Compressor
On
Other Compressors On Compressor starting
inhibited for maximum
pull down rate
Dead band
zone
# Compressors On
1
2
3
4
Compressors start-up sequence - Cool
mode
Time
Time