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HEMNVx & HEMSL Range Users, Installation & Servicing Instructions Doc Ref M103 issue 3.6 Mar 2020.
Gas Safety (Installation & Use) (Amendment)
Regulations
It is law that all gas appliances are installed,
adjusted and, if necessary, converted by
qualified persons* in accordance with the
current issue of the above regulations.
Failure to install appliances correctly can lead to
prosecution. It is in your own interests and that of safety
to ensure that the law is complied with.
* Gas Safe Registered Engineer
Checks to ensure electrical safety must be carried out by
a qualified person
and must include.
i) Ensure that a two pole electrical isolator having a
minimum separation between pole of 3.0mm is fitted
adjacent to the module.
ii) That the correct value fuse and cable size has been
used.
iii) That the module is correctly earthed.
iv) That polarity at the module is correct.
v) That connections to the module are as per the wiring
diagram.
vi) That the main air fan is interlocked with the module so
that the module will not function if there is no air flow.
vii) That installation wiring has not been routed adjacent
to components that will become hot when the module is
working. e.g. burners, exhaust header box.
For new installations, the whole of the gas installation,
including the meter, should be inspected and tested
for soundness and purged in accordance with the
recommendations of IGE/UP/1 (Edition 2) or IGE/UP/2A
as appropriate.
The following preliminary checks should be made before
lighting the heater(s)
a) Ensure that the ELECTRICAL supply to the heater is
switched OFF.
b) Check that all warm air delivery outlets are open.
c) Check that all external controls are calling for heat.
d) Ensure the external control/BMS is set to winter
operation.
1. Ensure that the gas service valve is closed.
2. Switch on the electrical supply at the isolator and
the ignition sequence will commence. After a delay of
approximately 45 seconds the ignition spark will be
generated and the main gas valve(s) energised.
3. If the limit indicator light comes on press the limit
thermostat reset switch on the front panel. The Red
indicator light will go out and the ignition sequence will
commence. After a delay of approximately 45 seconds the
ignition spark will be generated and the main gas valves
energised.
4. The burners will fail to light as the gas service valve is
closed.
The control box will attempt ignition a further four times
and then go to lockout and the lockout light/reset switch
will be illuminated.
5. To restart the ignition sequence depress the lockout
light/reset switch for about 3 seconds.
NOTE: On initial lighting of the heater(s), it may
take some time to purge the internal pipe work
of air.
IMPORTANT: The internal pipe work of the
appliance has been tested for soundness
before leaving the factory. After establishing
the main burners test round the gas inlet
connection using a leak detection fluid.
1. Switch on the electrical supply at the isolator and
the ignition sequence will commence. After a delay of
approximately 45 seconds the ignition spark will be
generated and the main gas valve(s) energised.
2. If the burners fail to light the control box will complete
a further four ignition attempts. If at the end of five
attempts the burners have still not lit the control box
will go to lockout and the amber rocker switch will be
illuminated. To restart the ignition sequence depress the
illuminated reset button for about 1-2 seconds.
Set the external controls to OFF. If required, once the main
air fan has stopped or the module is cold, the electrical
supply to the module can be switched OFF.