Technical data

GENERAL INFORMATION AND TECHNICAL CHARACTERISTICS
Ed.06/2011 9
1.2 OPERATION OF THE UNIT
The F2 C Series gas fired unit heater is an independent heater appliance with airtight
combustion circuit and forced air draft.
It is designed for an indoor installation - inside the area to be heated.
It is adjustable for the use of Natural Gas (G20) and L.P.G. (G30/G31) (appliance
belonging to the II
2H3B/P
category according to the Standard EN 1020).
The combustion circuit is airtight regarding heated room and conforms the standard EN
1020 for the C type appliances: the air inlet of the combustion air and the flue exhaust are
outdoors and are ensured through the operation of combustion blower.
The heater operation is controlled by a room thermostat on demand (available as
accessory). When the thermostat is turned on the flame control box, after the pre-purge
period (about 40 seconds), ignites the burner.
The flame sensor controls the ignition of the burner. If the flame does not appear the
flame control unit locks out the heater.
The combustion products pass through the heat exchangers, the air flow given by the
centrifugal fan provides warm air to the room.
The fan control thermostat allows the axial-flow fan to start automatically only when the
heat exchangers are hot (after about 60 sec. from the flame detection or when the
temperature of 60°C is reached on the exchanger thermostat) and to turn off when they
are cold. This prevents cool air from being blown into the room.
If heat exchangers overheat due to malfunction, the temperature limit thermostat cuts off
the supply to the gas valve by setting the blower and the fan; should the temperature
increase further, the limit thermostat comes into operation causing the switching off of the
heater. The limit thermostat reset is manual.
!
After removing the cause of overheating, Qualified service engineers should carry
out resetting of the temperature.
Ahead of the burner the flue fan is installed which makes the air-gas mixture and forces
draft of the exhaust flues.
Ahead of the burner the flue fan is installed which makes the air-gas mixture and forces
draft of the exhaust flues.
In case of obstructions in the exhaust or intake duct or in case of blower malfunction, the
flame control box reduces automatically the combustion air and consequently the gas flow
rate. In case of obstructions or malfunction beyond the allowed limits, the differential
pressure switch closes the gas valve and consequently stops the fuel flow to the burner.
In the summer time it is possible to activate only the axial fan to provide pleasant and
refreshing air movement in the room (for more information see Paragraph “SUMMER
OPERATION (COOLING)” at page 15).