Section 4 – Installation
The smoke detector is installed in the Extract duct. Alternatively, an external fire alarm system can be used.
NOTE!
If an external smoke detector is not used then a link wire must be fitted across the “Smoke
Detector” terminals on the Main Connector PCB. (See section 4.5.1 Installation of the smoke
detector bypass Link Wire).
4.5.9 Installation of the External duct heaters. (Only applicable to Natural Air 180/350 PH models)
The preheater is for frost control, and the external post heater can be connected to the unit to ensure the
supply air temperature is acceptable.
The preheater is fitted into the Fresh air duct and must be adequately thermally insulated. *
The post heat (Boost) is fitted into the Supply air duct and includes its own temperature sensor. *
The airflow direction is indicated by arrows on the duct heater unit.
Both units are powered directly from the ventilation unit.
Connect the 230V 50hz supply (from the ventilation unit) to the terminal block inside the heater
enclosure.
A post heat (boost) duct heater also requires a wired connection for the internal thermistor to the NTC
terminal on the EMC Terminal Block PCB.
* Only use heater units as listed in the User Handbook Accessories. (Installation notes supplied with units).
Fig. 4.13a Connecting the duct heaters to the 180 unit
Fig. 4.14 Connection for Boost heater NTC
thermistor to TB1 (Terminals 1 and 2).
Fig. 4.13b Connecting the duct heaters to the 350 unit
1 Power supply to External Pre-heater unit.
2 Power supply to External Boost heater unit.
3 Inlet glands for external sensors (and NTC thermistor for Boost heater unit).
(Remove a grommet and make a suitable hole through the exposed EPP insulation into the wiring chamber)
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