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OPERATION
6.
6.1 GENERAL INFORMATION
The unit is not provided with an independent control for the start-up and shutdown of internal parts. However, the relevant
signals come from the outside via specific connections provided in the electric control board.
A check on the pressure value, generated by the pump to the primary circuit that is measured by the pressure probe
available in the circuit, is automatically performed.
If secondary circuit pumps are available, they will be equipped with pressure probes too.
The speed of the pumps is adjusted by the inverters so as to keep the value of the increase in pressure generated by the
pumps steady, as the flow rate varies.
The operation rotation logic of the pumps is also managed independently if backup pumps are available as accessories.
6.2 START-UP OF THE UNIT AND MANAGEMENT OF THE PUMPS
The unit can be provided with one or two pump units; one to the primary circuit (always present, and operating with glycol in
variable percentages between 20% and 40%), and the other to the secondary circuit (supplied as optional and operated with
water).
The authorization to operate the unit and to start the primary circuit pump (the only ever present, even in "basic" model) is
subject to the simultaneous occurrence of two conditions, namely: 1) UTA in operation; 2) achieving the minimum threshold
of opening level of one of the two valves available. Once started, the pump will switch off when one of the two following
conditions occurs: 1) UTA shutdown; 2) complete closing of both two-way modulating valves.
The secondary circuit pump (optional) is started at the same time as the GOLD treatment unit, and is switched off only when
the Gold unit goes off (fans stop). For this reason it is necessary to equip the secondary circuit with a by-pass calibration
valve that allows a minimum water flow even when the beams are not completely powered.
If there are 2 pumps in parallel (one as a back-up pump), the exchange between the two will occur is case of failure, or at
least periodically to ensure uniformity of operation time.
The speed of the pumps is always adjusted by an inverter that receives a signal from a pressure probe installed on the
related circuit. The aim is to maintain a constant pressure level in the circuit at different pump speed with any degree of
opening of the available two-way valves.
The two-way valve internal to AQUA Link has the aim to adjust the temperature of the water sent to the circuit of the chilled
beams, a value established by the All Year Comfort control. The 0-10 V signal that drives this valve must come from a
temperature probe installed on the flow of the secondary circuit (see par. 3.1).
A second two-way valve (not installed internally to AQUA Link but provided on the UTA), controls the water flow to the UTA
battery. The adjustment of this valve is completely entrusted to the control installed on Gold.
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