Section 14: Operation; Heater Lockout Indication (Optional); Figure 35: Sequence Of Operation Chart - Roberts Gorden Blackheat BH15UT Installation, Operation & Service Manual

SECTION 14: OPERATION

DANGER
Electrical Shock Hazard
Disconnect electric
before service.
More than one
disconnect switch may
be required to
disconnect electric from
heater.
Heater must be
connected to a properly
grounded electrical
source.
Failure to follow these instructions can result in death, electric shock, injury or property damage.

Figure 35: Sequence of Operation Chart

KEY TO
SYMBOLS
Thermostat
Fan
Pressure
P
Switch
Neon
Ignition
Gas
Valve
Flame
Sensing
Lockout Alarm
Signal (optional)
NOTE: If the heater operates for more than 24 hours continuously, the ignition module will automatically recycle the
burner to ensure that all safety functions are still in working condition.

14.1 Heater Lockout Indication (Optional)

In case of flame loss during operation of the heater, the
burner control unit goes to lockout mode after three
ignition trials. At this stage a signal or closed relay will
enable the ROBERTS GORDON
Explosion Hazard
Turn off gas supply to
heater before service.
T0 T1 T2
P
Fan Neon
Burner Neon
Tp
10 sec
40 sec max.
11 sec typical
® controller, BMS
WARNING
Burn Hazard
Allow heater to cool
before service.
Tubing may still be hot
after operation.
T3 T4
Interruption of main
flame sensing
system, etc. to indicate precisely which heater has failed.
This can be done by two options.
SECTION 14: O
Cut/Pinch Hazard
Wear protective gear
during installation,
operation and service.
Edges are sharp.
T5 T6 T7
Tp Ts
10 sec 10 sec
Burner Lockout
signal received after
3 ignition trial
PERATION
T8
failures
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