Baxi Luna 3 Comfort Manual Para El Usuario Y El Instalador página 33

28. HOW TO PURGE THE DHW SYSTEM FROM LIMESTONE DEPOSITS
(Not fitted on 1.240 i - 1.240 Fi and 1.310 Fi models)
To clean the DHW system it is not necessary to remove the DHW heat exchanger if the assembly is equipped with the
appropriate taps (supplied on demand) placed on the hot water outlet and inlet.
To carry out the purge it is necessary to:
• close the cold water inlet
• drain the DHW system from the water contained therein by means of a hot water tap
• close the DHW outlet
• unscrew the two stop cocks caps
• remove the filters.
In case the appropriate tap is not supplied it is necessary to disassemble the DHW heat exchanger, as described in the fol-
lowing section, and do the purge aside. We recommend you also purge from limestone deposits the DHW heat exchanger
seat and the NTC sensor fitted on the DHW system.
To purge the exchanger and/or the DHW system we suggest the use of Cillit FFW-AL or Beckinser HF-AL.
29. HOW TO DISASSEMBLE THE DHW HEAT EXCHANGER
(Not fitted on 1.240 i - 1.240 Fi and 1.310 Fi models)
The stainless steel plate-type DHW heat exchanger is easily disassembled with a screwdriver by operating as described
below:
• drain, if possible, only the boiler system, through the drain tap;
• drain the DHW system from water;
• remove the two screws (right in front of you) securing the DHW heat exchanger and pull it off its seat (figure 19).
30. CLEANING THE COLD WATER FILTER
(Not fitted on 1.240 i - 1.240 Fi and 1.310 Fi
models)
The boiler is equipped with a cold water filter
placed on the hydraulic assembly. To clean it do
the following:
• drain the DHW system from water;
• unscrew the nut on the flow sensing assembly
(Figure 19);
• pull out the flow sensing device and its filter;
• remove the impurities.
Important: in the event of replacements and/or
cleaning of the O-rings on the hydraulic unit, do
not use oil or grease as lubricant but exclusively
Molykote 111.
To optimise boiler efficiency, carry out the following annual controls:
• check the appearance and airtightness of the gaskets of the gas and combustion circuits. Replace any worn seals with
new original spares;
• check the state and correct position of the ignition and flame-sensing electrodes;
• check the state of the burner and make sure it is firmly fixed;
• check for any impurities inside the combustion chamber.
Use a vacuum cleaner to do this;
• check the gas valve is correctly calibrated;
• check the pressure of the heating system;
• check the pressure of the expansion vessel;
• check the fan works correctly;
• make sure the flue and air ducts are unobstructed;
• check for any impurities inside the siphon fitted on certain boilers;
• check the magnesium anode, where present, for boilers fitted with storage boilers.
WARNINGS
Before commencing any maintenance operations, make sure the boiler is disconnected from the power supply.
Afterwards, move the knobs and/or operating parameters of the boiler to their original positions.
INSTRUCTIONS PERTAINING TO THE INSTALLER
Figure 19
31. ANNUAL MAINTENANCE
33
flow sensing securing nut
DHW heat exchanger securing screws
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