The gas valve unit DUNGS MB - DLE... is made up of:
1) A safety valve which closes opens rapidly.
2) A principle valve which opens in two stage (5). The first opening stage occurs rapidly (release) and is adjustable by
unscrewing the knob (2) and inserting the back part of the regulating pin underneath. The + and symbol can be seen
on the head of the valve and these indicate the direction in which the pin should be turned in order to increase or the
ignition output (the first stage of the valve opening). By rotating in a clockwise direction, the initial delivery (ignition
flame) can be reduced; in an anti-clockwise direction, the initial delivery is increased. The complete run from zero to
maximum, and viceversa, is slightly more than three turns (40% of the total opening). When the first opening stage
has taken place, the valve comtinues to open slowly and takes 15 seconds to reach the maximumopen position. To
regulate maximum delivery desired, loosen the locking screw (4) (the one with the protruding head and not the one
locked and sealed with paint) and turn knob (3). Rotate in a clockwise direction to reduce delivery and in anti-
clockwise direction to increase it. It should be pointed out that when the regulating knob is turned, the end - of - the -
run which limits the operating of the valve moves; therefore, when the knob has been turned untilit reaches the - sign,
the valve will not open and the burner will not ignite. To get ignition, it's necessary to turn the knob in an anti-clockwise
direction towards the + sign. The complete run from zero to maximum and viceversa is neary six turns of the knob. This
regulating operation (for maximum and ignition output) must be carried out without forcing against the end - of - the -
run - positions.
3) The pressure stabilizer (10) can be regulated (see table) by manoeuvring the screw which can be reached by sliding
the cover (1) to one side. The complete run from the maximum to the position and viceversais about 80 turns. Do not
force against the end - of - the - run positions. Around the screw are arrows with symbols which indicate the sense of
rotation: to increase pressure, rotate in a clockwise direction, to reduce it, rotate in an anti-clockwise direction. This
stabilizer hermetically closes "upstream" and "downstream" when there is no flow of gas. Dfferent springs to obtain
different pressure value from those described above are not foreseen. To regulate the pressure stabilizer, connect
a water manometer to the rubber tube holder installed on the tap (8) in correspondence with the exit of the
stabilizer.
4) The small entry filter (12) can be reached for cleaning by removing one of the two side closing plates.
5) The minimum pressure switch (14). To regulate it remove the transparent cover and operate the black knob. The
reference mark is the small rectangle to be found on the yellow disk which the regulating knob rotates around.
6) At entry, a tap (13) has been fitted to the connction flange to measure the entry pressure. At the exit of the connection
flange, there is also a tap (7) to measure the pressure in exit.
7) The side pressure taps (9), indicated as Pe, are in communication with the entry pressure.
8) The side pressure taps (8) indicated as Pa, are used to measure the pressure coming out of the stabilizer. It might
be useful to know, that the pressure coming out of the valve unit (to be measured at tap 7), corrisponds to the pressure
regulated by the stabilizer and is reduced in order to overcome the crossing resistance of the principle valve (5). It
should be pointed out, that the valve crossing resistances depend on the opening of the valve regulated by knob 3
through wjich the end - of - the - run position is adjusted. To regulate the pressure stabilizer, connct a water
manometer to the rubben tube holder installed on tap (8) in correspondence to the stabilizer exit (Pa).
9) The holes of the pressure stabilizer bleed (11) should be free and unblocked if it's to function properly.
SUGGESTIONS FOR REGULATING THE GAS VALVE
1) Connect a water manometer to the pressure tap Pa (indicated as n° 8) to measure the pressure coming out of he
stabilizer.
2) Put the gas delivery regulators for ignition (2) and for maximum delivery (3) in the positions presumed necessary for
the delivery desired. Also open adequately the combustion air regulator.
3) Turn on the burner.
4) With the burner on, manoeuvre the regulating screw (1) of the stabilizer regulator of the gas pressure and regulator of
the gas pressure and regulate the pressure at the value considered necessary to obtain the output desired, when the
maximum output regulator (3) is in the maximum opening position. It should be pointed out that, normally, the above
conditions require about 40 ÷ 70 mm.W.C.
5) Put the ignition output regulator (2) in the position considered necessary to obtain ignition with the minimum delivery
possible.
VALVE
INLET MAX PRESSURE
MODEL
MB ...403 B01 S 20
MB ... .... B01 S 20
COMBINED DUNGS VALVE (monobloc)
mod.MB-DLE...B01
ADJUSTTABLE OUTLET PRESSURE
(PE) mbar
200
360
36
FROM THE STABILIZER (PA) mbar
from 4 to 20
from 4 to 20
N° 0002910301
REV. 16/02/2004
TYPE OF GAS
Natural gas / L.P.G.
Natural gas / L.P.G.