27
Regulation and servicing
fo
r the technician
Changing Gas type
ATTENTION: the operations described below must
be carried out only by qualified personnel
[authorized from HERMANN Ltd]
.
For gas conversion, use the nozzles supplied by boiler
manufacturer only.
CONVERSION FROM NATURAL GAS TO L.P.G.
Using LPG, it is absolutely necessary to install a
pressure reducer upstream the boiler.
1. Disconnect the boiler from the electrical supply.
2. On “SE” models, open sealed combustion chamber.
3. Remove pipe between gas valve and injectors bar.
4. Remove injectors bar and replace injectors with the ones
suitable for L.P.G., using a 7 mm. spanner (see figure
“BURNER”). Reassemble injectors bar and pipe,
replacing gaskets. On “SE” models, close sealed
combustion chamber;
5. Remove the cover of the control panel and move the first microswitch of SW3 (on the right) in
the position ON, indicated in the figure with “GPL”.
6. check that pressure upstream the boiler is: Buthane = min.25 - max.35 mbar or Propane =
min.25 -max.37 mbar.; check for gas leaks;
7. repeat following regulations: Domestic Water Output (max. and min.), Slow Opening Pressure
and Heating Output, carefully reading the instructions given in the previous pages.
CONVERSION FROM L.P.G. TO NATURAL GAS
1. Disconnect the boiler from the electrical supply.
2. On “SE” models, open sealed combustion chamber.
3. Remove pipe between gas valve and injectors bar.
4. Remove injectors bar and replace injectors with the ones suitable for Natural Gas, using a 7
mm. spanner (see figure “BURNER”). Reassemble injectors bar and pipe, replacing gaskets.
On “SE” models, close sealed combustion chamber;
5. Remove the cover of the control panel and move the first microswitch of SW3 (on the right) in
the position OFF, indicated in the figure with “MET”.
BURNER
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