Daikin EWAD TZ-B Operation Manual

Also see for EWAD TZ: Installation, operation and maintenance Installation, operation and maintenance manual

Contents

Daikin EWAD TZ-B Operation Manual Manual pdf 40 page image

Air and Water cooled inverter chillers and heat pumpD-EOMZC00105-17ENOperation Manual40/84EWAD TZ - EWAD TZ B -EWWD VZAir and Water cooled inverter chillers andheat pump5.1.4 Alarm SettingsIf glycol is present in the water circuits, factory defaults values for the Alarm Limits listed below must beadjusted:Parameter DescriptionLow Press HoldSet the minimum refrigerant pressure of the unit. It is generally recommended to set to a value whose saturatedtemperature is 8 to 10°C below the minimum active setpoint. This will allow a safe operation and a proper controlof compressor suction superheat.Low Press Unload Set lower than the hold threshold enough to allow a suction pressure recovery from fast transients withoutunloading the compressor. A 20 kPa differential is generally appropriate for most applications.Evap Water FrzStops the unit in case the leaving temperature falls below a given threshold. To allow a safe operation of thechiller, this setting must be adequate to the minimum temperature allowed by the mixture water/glycol present inthe evaporator water circuit.Cond Water Frz(W/C units only)Stops the unit in case the leaving temperature falls below a given threshold. To allow a safe operation of thechiller, this setting must be adequate to the minimum temperature allowed by the mixture water/glycol present inthe condenser water circuit.When glycol is used in the plant, always disconnect antifreeze electric heater.5.1.4.1 PumpsThe UC can manages one or two water pumps for both evaporator and, for W/C units, condenser.Number of pumps and their priority can be set from the menu in 4.2.4.The following options are available to control the pump(s):#1 Only Set to this in case of single pump or twin pump with only #1 operational (f.e. in case of maintenance on #2)#2 Only Set to this in case of twin pump with only #2 operational (f.e. in case of maintenance on #1)Auto Set for automatic pump start management. At each chiller start, the pump with the least number of hours will be activated.#1 Primary Set to this in case of twin pump with #1 running and #2 as a backup#2 Primary Set to this in case of twin pump with #2 running and #1 as a backup5.1.5 Power Conservation5.1.5.1 Demand LimitDemand limit function allows the unit to be limited to a specified maximum load. Capacity limit level is definedwith an external 4-20 mA signal and linear relationship. 4 mA indicate maximum capacity available whereas20 mA indicates minimum capacity available.With demand limit function is not possible shutdown the unit but only unload it until minimum admissiblecapacity. Demand limit related setpoints available through this menu are listed in the table below.Parameter DescriptionUnit Capacity Displays current unit capacityDemand Limit En Enables demand limitDemand Limit Displays active demand limitCapacity Limit[%]MinimumCapacityMaximumCapacity204 Demand Limit[mA]