Hamworthy F175H, Инструкция по установке, вводу в эксплуатацию и эксплуатации

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HAMWORTHY HEATING LTD
39
FLEET H series 500001216/D
9.0 FAULT FINDING
The Fleet boiler is equipped with full self-diagnostic fault indication, with faults allocated a code, which is
displayed (flashes) on the display - refer to
section 8.3.9 - Maintenance functions.
The common fault codes are detailed in
section 8.3.9 - Maintenance functions. . Fault codes not detailed in this
manual should only be investigated by an Engineer.
Should a fault code appear which cannot be reset, or a fault code repeatedly occurs,
contact Hamworthy Heating for assistance. Do not continue to operate or use the boiler
as this may cause damage to the controls.
9.1 Safety Temperature Limiter (Limit Thermostat)
1. The electronic control thermostat has several safety levels built in such that a controlled shutdown should occur
before the safety temperature limiter is activated. Should these safety levels be overridden (say external pump
overrun failure after shutdown) the safety temperature limiter will trip initiating a boiler shutdown, preventing the
boiler from firing. The code
(110) on the controls display will flash indicating that the safety temperature limiter has
tripped.
2. The safety temperature limiter is auto reset located on the top rear of the heat exchanger block. Once the
boiler has cooled to normal operating temperature, pushing the reset pushbutton on the display (refer to
section
8.1.1 - Controls Operation ) will reset the lockout. Should the lockout code not extinguish and the boiler does not
fire up, it is possible that the safety temperature limiter will not reset because the boiler is still too hot.
3. Always carry out an investigation to ascertain the reason for overheating. The most common cause of
overheating is lack of water flow rate through the boiler possibly caused by a faulty pump or blockage in the heat
exchanger circuit due to system debris.
Figure 9.2 - Water Flow Switch
9.2 Water Flow Switch
1. The water flow switch is
located in the return pipe before
the pump and the heat
exchanger
(see figure 9.2) and
will prevent the boiler from firing
should there be inadequate or
no water flow. This is to protect
the heat exchanger from
damage in the absence of water
(dry firing) which will cause
catastrophic failure of the heat
exchanger.
2. The operation of the flow
switch can be checked by
closing one of the isolating
valves connecting the boiler to
the system, this will generate
error E164 on the LMU display.
9.3 Ignition Controller
1. The flame is under constant supervision by the burner ignition controller. The controller monitors the flame’s
ability to rectify an AC current. If the flame diminishes for whatever reason and the rectified current drops below
the controller’s minimum detection current (3µA DC), the controller will de-energise the gas control valve within 1
second and commence a restart. Failure to establish and detect a flame during the light-up sequence will result in
burner shutdown and lockout within 5 seconds, requiring a manual reset to restart the ignition sequence. Refer to
section 8.3.9—Maintenance functions. .
2. If the boiler continues to lockout, then an investigation must be made to ascertain the cause. Refer to figure
8.3.10 - Operating faults , for possible causes of lockout.
3. A false flame signal at the start and during pre-purge will cause the boiler module to restart its ignition se-
quence at the end of the pre-purge period. If this occurs 3 times in succession the controls will disable operation
of the boiler module, requiring reset of the module. Refer to
section 8.3.10 - Operating faults