Roberts Gorden HE20ST Operation, Electrical Shock Hazard, Burn Hazard, Disconnect electric

SECTION 14: OPERATION

SECTION 14: OPERATION

DANGER		WARNING
Electrical Shock Hazard	Explosion Hazard	Burn Hazard	Cut/Pinch Hazard
Disconnect electric	Turn off gas supply to	Allow heater to cool	Wear protective gear
	heater before service.	before service.	during installation,
before service.
			operation and service.
		Tubing may still be hot
More than one			Edges are sharp.
disconnect switch may		after operation.
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 33: Sequence of Operation Chart

KEY TO

SYMBOLS

Thermostat

Fan

Pressure

P Switch

Neon

Ignition

Gas

Valve

Flame

Sensing

Lockout Alarm

Signal (optional)

T0	T1	T2	T3	T4	T5	T6	T7	T8
P
Fan Neon
Burner Neon
		Tp			Tp		Ts
	10 sec				10 sec		10 sec
	40 sec max.				Interruption of main		Burner Lockout
11 sec typical					flame sensing		signal received after
							3 ignition trial
								failures

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® controller, BMS system, etc. to indicate precisely which heater has failed. This can be done by two options.

14.1.1 Heater Lockout Indicator by Connector

A 230 V signal is provided which enables the ROBERTS GORDON® controller, BMS system, etc. to indicate the heater that has failed. An additional wire has to be installed from the heater lockout indicator connector to the monitoring computer. See Page 56, Section 13.5.

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