Robinson Willey Bantam Ecotherm LPG, Руководство пользователя

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The spark generator: a buzzing noise is heard and sparks can be seen through the window at the
right hand side of the heat exchanger.
4. The gas at the burner is ignited. A circuit on the control board detects the flame and maintains the
heater in the normal operating condition. The flame can be observed in the window at the right hand
side of the outer case. The detection current should be greater than 3uA. The detection current is
measured by removing the connection from the detection electrode and inserting an ammeter with a
minimum f.s.d. of 10 uA. This must be done before the heater is switched on.
5. The heater continues to operate and is switched on and off automatically in accordance with the
heating programme set on the clock and thermostat. Note that the heater operates at full rate when
heat is required and is switched off when heat is not required. There is no low or by-pass rate.
Operation in Fault Conditions
1. If, in item 4 of Normal Operation above, the gas is not ignited, the spark generator will continue to
operate for approximately 9 seconds. This time is called the ignition period. At the end of the ignition
period the circuit on the control board causes the valve to close and switches off the convection fan
and spark generator. The red lamp goes out and the amber lamp remains on. This condition is known
as the 'lock-out' condition. The heater cannot be re-lit until the electrical supply is broken and re-
made, by turning the control knob to the OFF position or operating the override switch.
2. If, while the heater is running normally, the flame fails because of:-
Combustion air failure
Gas failure
Overheat switch operation
The heater will revert to the 'lock out' condition. If, when the heater is switched on the control board
has a fault which simulates the presence of a flame at the burner, the heater will revert immediately to
the 'lock out' condition without attempting to light.
Possible Faults
When examining the heater for faults, switch it off, and then switch it back on. Observe what happens and
compare with the pattern of operation noted above. A test instrument for checking voltage and electrical
continuity is very useful. If a control board fault is suspected, check by substituting a spare control board.
The following are possible fault conditions:-
Fault Check
1. Combustion fan does not start Main switch and fuse is fitted. Clock is in an 'On' period
(Warmplan XX Auto). Thermostat setting is above room
temperature.
Connections to main switch on thermostat.
Combustion fan and connections.
2. Combustion fan starts but purge Connections from main terminal block to control board
period does not end. terminal block.
Possible control board fault.
3. Heater reverts to lock out condition Gas supply. Purge gas line on a newly installed heater.
without ignition after normal Solenoid valve operation and electrical connections.
purge and ignition periods. Injector for blockage.
Spark electrode gap and electrode setting in relation to the
flame port in the burner.