SqurboXbox Twinfan Consultants Specification
OperationThe supply and extract ventilation unit shall be as indicated on the drawings and shall be in accordance with the particular fan schedule in the specification. Supply air to the room shall be pre-heated by the extract air via the integrated heat exchanger block. Where fitted an integrated heater battery shall raise the temperature of the supply air to the design room temperature after the air has passed through the heat exchanger. The ventilation unit shall automatically vary the ventilation rate, as it receives signals from one of the optional interconnected sensors. When signals are received, the fan shall either vary its speed proportionally or on a trickle and boost principle. The unit shall have the facility to commission the supply and extract fans individually via inbuilt minimum and maximum speed adjustment, the fans themselves shall have infinitely variable speed control.
squrboXbox twinfans - unit specification
Unit sizes 2 - 6 shall be manufactured from aluminium alloy with 25mm infill panels, giving extremely low noise levels.* It shall be come c/w a high efficiency heat exchanger block, supply and extract filters, automatic summer bypass, integral minimum and maximum infinitely variable speed controls, run on timer and facia mounted failure indication. The unit shall have low energy, high efficiency a.c. fan/motor assemblies with sealed for life bearings. The impellers shall be high efficiency mixed flow or centrifugal type.
The unit shall have a heat exchanger block with a thermal efficiency of up to 55 - 70% that shall be protected by G4* grade pleated filters on supply and extract. It shall come complete with a condensate drip tray and 22mm drain connection. Alternatively a condensate pump shall be provided if specified.
The unit shall be constructed with removable panels allowing full maintenance access from the side (access handing to be confirmed in product code and verified on site prior to order). The removable panels shall provide access to the following:
- Supply or extract fan
- Supply & extract filter
- Heat exchanger block
- Heater battery temperature adjustment (where included)
- LPHW Heater pipe connections. (where included)
- Speed control commissioning adjustment (min & max)
- Electrical connection terminal blocks
- 2 fans incorporate auto change over in the event of one fan failing
* Other filter specifications including high capacity filters & grade F7 available as integrated options.
squrboXbox twinfans - standard controls
All versions shall incorporate the following functions integrally mounted, pre-wired and factory fitted by the manufacturer:
- Integral infinitely variable speed control on supply and extract
- Integral background ventilation control/set point
- Integral boost ventilation control/set point
- Integral BMS interfaces – summer/winter switching, heating control**, 0-10v speed adjustment
- Integral run on timer
- Volt free failure indication (direct from individual fan)
- Integral S/L terminal for boost trigger from remote switch, e.g. lightswitch
- Integral air off coil temperature adjustment**
- Multiple IDC sockets for interconnection of up to 6 ECOSMART sensors, controllers or fans using pre-plugged 4-core low voltage cable
- Volt free frost alarm/heat demand interface**
- Frost protection/hold off stat**
- The unit shall be controlled by the ECOSMART control devices (enablers & sensors) as detailed in the schedule on the drawings
- LPHW pipework connections c/w diverting valve and actuator
Coil types and controls
The control for the coils shall be fully integrated and shall maintain a constant off coil temperature. The system shall have frost protection which shall, at temperatures below 4 degrees C, fully open the 4-port valve and only start the fan when the temperature at the filter has risen above the designated set point.
The Low Pressure Hot Water heating coil shall be factory fitted with a 3 or 4 port valve, drain cocks and air vents. The actuator controlling the 3 or 4 port valve shall be controlled via the on-board PCB by the off coil temperature sensor. All components pre-piped, assembled and tested by the manufacturers.
The Electric Heater Battery shall be factory fitted and pre-wired to an integral closed loop thyristor control. When the unit is switched off, the fan shall continue to run to dissipate heat from the electric heater battery before stopping.
The Fan unit shall have a 5 year warranty, first year parts and labour the remainder parts only.
The manufacturer’s recommendations should be observed at all times.
The unit shall be the squrboXbox and shall be manufactured by Nuaire.
