baltur COMIST 180 DSPNM, User Instruction Manual

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0006080118_201311
VarianT fOr BUrner eqUiPPeD WiTH a
sTeam PreHeaTer fOr THe LiqUiD fUeL
The burner may be equipped with a steam-operated fuel oil preheater
that makes it possible to heat the fuel with steam thereby saving
electricity.
This device consists of a small tank in which the steam circulates,
inside of which there is a coil in which the fuel oil to be heated
circulates. This particular implementation makes it possible to
considerably decrease the size of the preheater.
When the burner is switched on, the cold fuel oil would be forced
to pass through the steam preheater coil while still cold because it
has not been supplied with steam.
The high viscosity of the fuel (cold), the considerable length of the
coil and its relatively small diameter (necessary for a higher heat
exchange) would cause a considerable pressure loss and, as a
result, the fuel would reach the nozzle with an insufficient pressure.
To prevent this unacceptable situation, the steam preheater is
equipped with a manual by-pass damper that makes it possible,
when open, to prevent passing through the coil (see 8576).
insTaLLaTiOn
The User must install a gate valve, a suitable pressure reducer
(adjustable between 1 and 8 bar) and a control pressure gauge (full
scale 10 bar) on the pipe that directs the steam to the fuel heater.
Do not collect the condensation that is discharged from the heater
to avoid, in the case of coil loss, taking fuel oil into the steam unit.
regULaTiOn
When the boiler has reached a pressure that seems sufficient, the
damper opens, this allows the steam to flow to the oil heater, the
"air release" damper located on the condensate outlet pipe will
open slightly.
While the steam vents from the gate valve slightly open, it adjusts
the pressure reductor to a sufficient level to heat the fuel oil to a
slightly higher temperature (around 10 - 15° C) to that which the
electric heater's thermostat regulator has been set. A preliminary
regulation is obtained by regulating the pressure reducer based on
the value indicated on the pressure gauge. The regulation can be
corrected if necessary after checking the temperature of the fuel
exiting the steam heater.
Once the adjustment is complete the air release gate is closed.
The electric heater thermostats (minimum and regulation) must
be adjusted normally as described in the chapter “Ignition and
Regulation”.
Pressione vapore al manometro bar 1 1,5 2 2,5 3 3,5 4 4,5 5 6 7 8
Temperatura approssimativa corri-
spondente °C
120 127 133 138 143 147 151 155 158 164 169 174
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