Cuenod NC12 - Setting Air Pressure Switch; Start-Up; Preliminary Checks; Leakage Test

10/2007 - Art. Nr. 13 017 700B 7
Start-up
Preliminary checks / leakage test
Setting air pressure switch
Burner start up simultaneously involves
starting up installation by the fitter or his
representative; only they can guarantee
boiler house compliance with currently
accepted practices and regulations in
force.
The fitter must first be in possession of a
“certificate of gas fuel conformity ”
issued either by the approved body or
distributor and also have leak-tested and
drained pipework upstream from the
quarter-turn hand-operated valve.
Preliminary checks
• Check the following:
- nominal available voltage and
electrical frequency and compare
them with values found on
identification plate,
- polarity between phase and neutral
- previously tested earth wire
connection,
- lack of potential between neutral and
earth,
• Make sure there is no current.
• Close fuel valve.
• Read boiler and regulator
manufacturer service instructions.
• Check the following:
- boiler is full of pressurized water,
- circulator(s) work(s),
- valve(s) open,
- combustion air supply to the boiler
house and combustion product
exhaust pipe are working correctly
and compatible with burner capacity
and fuel,
- electrical protection equipment
outside burner are present,
calibrated and set,
- boiler regulator circuit is set.
- gas type and distribution pressure
are suited to the burner.
Setting air pressure switch
• Check the connection of the flexible
piping of the pressure tap on the + of
the pressure switch.
• Remove transparent cover. Unit
includes a  index and graduated
mobile disk.
• Provisionally set pressure controller to
the minimum value shown on
graduated disk.
Leakage test
• Connect a pressure gauge to pressure
take-off located upstream from gas
manifold.
• Open quarter-turn hand-operated
valve.
• Check supply pressure.
• Use a purpose designed medium to
check air-tightness of gas manifold
connections, including external filter.
No leak should be found.
• Vent the pipe downstream of the
manual valve by a quarter of a turn
whilst protecting the gas valve inlet.
• Reclose drain valve.