Roberts Gorden Dualair DA260G Series, Installation, Comissioning, Service & User Instructions

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4.10 Air Handling Controls
4.10.1 Pressure Switches
The pressure switches for the air filters and cooling coil should be set on site so that the cooling
equipment is protected against reduced air flow.
The pressure loss across the coil and filters as new and clean should be measured and a sensible
margin estimated to allow for increasing pressure loss as the filters become dirty.
The maximum loss across the filter alone should not be allowed exceed 150Pa (1.5 mbar) when the
filters are dirty.
The setting of pressure switches should be adjusted so that the filter pressure switch (2.11) operates
first to give warning of impending problems before the coil pressure switch (2.10) turns off the
condesers.
4.10.2 Coil Frost Thermostat
The coil frost thermostat should be set at approximately 4°C with a differential of 1°C to give the
cooling coil the protection it requires.
It is strongly reccomended that this control is connected and set to give the cooling coil
protection from freezing which would cause severe damage.
4.11 Handing Over
Ensure that all covers are fitted correctly and all test points are properly sealed before leaving the
appliance.
When the commission is complete explain to the user the controls of the heater including how to
operate the heater and cooling equipment ,how to turn safely off the equipment, using the controls
fitted on site.
Ensure that the user understands the need to check and replace the air filters at regular intervals i
accordance with these instructions.
Hand over these instructions to the user.
Ensure that the user is shown and understands the emergency instructions in Section 9 of this book.
WARNING
The electrical isolator should only be used in an emergency and should not be
used for closing down the burner, as this switches off the fan prematurely and may damage
the heat exchanger invalidating the warranty and causing a potential fire hazard.