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Packaged rooftop units
with integrated gas burner
11
Supply of
air from the
48EN/EH
unit
Safety
thermostat
bulb (F2)
The F2 blocking can be triggered when the safety thermostat bulb detects
an excessive temperature in the inlet air to the burner. The following
fi gure shows the position of the aforementioned bulb:
The burner remote control manages the burner protection devices by
detecting and indicating the following operating faults on its display:
Safety devices in the gas burner
Indication
Failure
Problem
F1
The burner does not
start.
Reversed phase and neutral.
No gas supply.
Connection without neutral.
No ground connection.
Problems with the fl ame detection
electrode.
The electrode nozzle is dirty or its
diameter is incorrect.
F2
Safety thermostat
High temperature in the exchanger.
Faulty thermostat bulb.
Presence of smoke.
Differential air
pressostat
The plastic conduit that enters the
pressostat is disconnected.
The discharge pipe and / or air inlet
pipe is (are) blocked.
Pressostat fault.
F3
The fan does not start
The fan wiring is wrong or
disconnected.
The voltage values for the modulation
are outside the range.
Failure in the fan motor.
F4, F5, F6
Unused
F7
No serial
communication
The remote control is disconnected.
F8
The fl ame control
device does not work
The fl ame control device is
disconnected or broken.
To unblock press
both keys for 3 seconds
The screen displays a fault
Green led: this indicates that
the unit is switched on
Unused
Red led: this indicates that the
burner is switched on
Blocks F1, F2, F3 and F8 are triggered by safety devices and require
manual resetting. To unblock press the up and down keys for 3 seconds
at the same time.
8. S
AFETY
ELEMENTS
Signalling pilot for
the switched on unit
Signalling pilot for
burner blocking
Transformer 230V/24V
Electronic modulation
board
Power supply
Connection for display
pilot lights
General switch
Flame
control
device
In order to access the gas burner control remove the door from the
auxiliary electric panel:
Burner remote
control
Gas burner switch
By removing the support box for the remote control access is gained
to the modulation board (0-10Vcc) and to the fl ame control device:
Support
box
In the event of failure, the burner control will send the CARRIERrtc
control a safety signal which will only be used as an indication (see the
electrical connections diagram in the previous chapter).
Summary of Contents for 48EH
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