Cleaning And Maintenance - Sime 30 PC Manual De Instrucciones

the intake downstream of the gas valve.
– Disconnect the valve VENT pressure test
point tube (5 fig. 21).
– Remove the cap (1) from the modulator.
– Place the hot tap water potentiometer
knob at the maximum position.
– Turn on the boiler using the four-way
switch and turn on a hot water tap all
the way.
– Remember that rotating clockwise will
increase pressure while rotating anti-
clockwise will diminish it.
– Adjust maximum pressure using the nut
(3) with a wrench to the maximum pres-
sure value indicated in Table 4.
– Do not adjust minimum pressure until
you have adjusted maximum pressure.
– Turn off the supply power to the modula-
tor, and keep the hot water tap turned
on.
– Lock the nut (3) in place, turn the screw
/nut (2) to the minimum pressure indi-
cated in Table 4.
– Turn off the boiler and turn it back on
again several times, keeping the hot
water tap turned on at all times and
checking that the maximum and mini-
mum pressure values correspond to the
established values; correct the settings if
necessary.
– Adjust, checking that you have restored
the power to the modulator.
– Put the pipe back on the valve VENT
pressure test point.
– Remove the manometer, remembering
to tighten the screw for closing the pres-
sure test point.
– Put the plastic cap (1) back on the modu-
lator and seal with a drop of coloured
sealant if necessary.
4.6 DISMANTLING THE CASING
The casing may be removed completely to
facilitate boiler maintenance, as shown in
fig. 23.
4.7

CLEANING AND MAINTENANCE

Carry out the cleaning of the generator in
the following way:
– Turn the main switch off to stop electric
power reaching the boiler and close the
gas feed cock.
– Remove the outer casing and the gas
burner manifold unit . To clean the bur-
ner, blow in a jet of air, so as to remove
any dust particles that may have accu-
mulated.
– Clean the heat exchanger, removing any
dust or residue from combustion. When
cleaning the heat exchanger or the bur-
ners, chemical products or steel bru-
shes MUST NOT BE USED.
Make sure that the tops of the burners
with the holes are free from encrusta-
tions.
– Reassemble the items removed from
the boiler, making sure to follow the cor-
SIT 845 SIGMA
1
2
KEY
1 Plastic tap
2 Minimum pressure adjusting nut
3 Maximum pressure adjusting nut
rect sequence.
– Check operation of the main burner.
– After assembly of all the gas connec-
tions, these must be tested for sound-
ness, using soapy water or appropriate
products. DO NOT USE NAKED FLAMES.
– Do not use calcium chloride to treat the
plastic component during generator
maintenance.
4.7. 1 Chimney sweep function (fig. 24)
To carry out the verification of combustion
in the boiler turn the selector and stop on
the position ( ) until the green/orange led
1
HONEYWELL VK 4105M
SIEMENS GVU 50
3
starts to flash intermittently.
From that moment the boiler will start func-
tioning in heating mode at the maximum
power, with switching off at 80°C and
restarting at 70°C.
Before activating the chimney sweep func-
tion make sure that the radiator valves or
eventual zone valves are open.
The test may be carried out also during hot-
water service functioning.
To do so it is enough, after having activated
the chimney sweep function, to take some
hot water from one or more cocks.
Even in this condition the boiler functions at
the maximum temperature always with the
primary controlled between 80°C and 70°C.
2
IT
ES
PT
GB
Fig. 22/a
Fig. 23
83