Aegis Sequencer
User Interface
L-OMM-015_0B
• 8/8/2023 Technical Support • (800) 433-5654 • Mon-Fri, 8 am - 5 pm EST
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4.2.1. Sequence of Operation
Temperature control is only active when the system is turned on. When the system is turned off (from
the keyboard, BMS, digital contact, etc.), the control panel only receives data from the units and displays
any anomalies (e.g. offline units).
The Aegis Sequencer activates the slave units in order based on the value of the temperature probes
positioned in the storage system. The BT1 and BT2 probes, which have two independent set points,
function as follows:
•
Probe BT1: If the set point for the BT1 probe is reached, other units can be activated, unless the
set point for the BT2 probe is reached.
•
Probe BT2: If the set point for the BT2 probe is not reached, a heat pump will be forced on, even
if set point on probe BT1 is reached.
•
Probes BT4
– BT9: The additional probes are associated with distinct points and differentials,
calculated by adding an offset to the set referred to as BTL. Except for the management
associated with the BT1 and BT2 probes, each unsatisfied set will raise the request for an
additional unit to activate.
See Section 4.3, User Menu, for more information on menu settings.
4.2.2. Anti-Legionella Management
The Aegis Sequencer includes a control algorithm called
“anti-Legionella function.” This function does
not apply to the North American market and should not be used because the required heat exchanger
module is not compatible with this feature. The information in this section is included for reference only.
The anti-Legionella function can be activated either on a set schedule or manually via the interface or
BAS.
NOTE:
The anti-Legionella function may be used to mitigate the risk of waterborne Legionella in the
tank array and near-tank piping. This function will not automatically disinfect building system piping.
A proper waterborne pathogen mitigation strategy should be used.
See ASHRAE Standard 188.
The BTL probe placed at the inlet of the heat exchanger is required to manage the anti-Legionella
function. The anti-Legionella cycle consists of two phases:
1. Phase 1
•
The "Anti-Legionella active" relay contact is closed.
•
All the units are forced to a set point value of 194
°
F [90
°
C] (settable value).
•
With BT1 up to Phase 1 Set BTL (e.g. 140
°
F [60
°
C] settable value), all heat pumps are
activated.
•
With BT1 over Phase 1 Set BTL, the system keeps only one unit active until the temperature
of the BTL probe reaches a predefined Phase 1 Set BTL set point, preset at 131
°
F [55
°
C].
The set point must be lower than the parameter ''Maximum inlet water temperature" set on the
Aegis unit. This function is only available on units with High Inlet Temperature function.
⚠
W A R N I N G !
It is recommended that this function, if used, be scheduled for periods of low demand to reduce the
risk of scalding. A master mixing valve and/or point-of-use mixing valve is required to prevent scalding.
Lync recommends the DigiTemp line of digital mixing valves.
