8.3 Special maintenance
Special maintenance must be carried out at the end of the season or for extended shutdowns.
All of the operations described in the previous section must be performed, in addition to the following:
- Check the condition of the turbulators for wear.
- After cleaning the flue gas circuit, wipe with a rag dipped in a diluted caustic soda solution. After letting it dry, wipe all surfaces with a
rag dipped in oil.
- Hygroscopic substances (quicklime, silica gel in small containers) should be placed inside the furnace, which must then be closed
hermeti-cally so air cannot enter.
- Do not empty the system or boiler.
- Protect the screws, nuts and pins on the door with graphite grease.
The operations performed must be recorded in the maintenance logbook.
8.4 Cleaning the boiler
To clean the boiler, proceed as follows:
- The boiler comes with a brush for cleaning the fire tubes.
- Open the front door (1) and remove the turbulators (2).
- Clean the inside surfaces of the combustion chamber and the flue gas path using a brush (3) or other suitable implement.
- Remove the deposits accumulated in the smokebox through the open cleaning door (4). For more thorough cleaning, remove the
smokebox (5) and replace the gasket before reassembling.
- Check periodically that the condensate drain (6) is not blocked.
8.5 Checking boiler operation
Before starting the boiler and running the functional tests, check that:
- The turbulators are inside the exchanger tubes.
- The cocks on the water circuit and fuel line are open.
- There is fuel available.
- The expansion vessel is suitably filled.
- The pressure of the water circuit, when cold, is over 1 bar and under the maximum limit for the boiler.
- The water circuits have been vented.
- The electrical connections to the mains power and components (burner, pump, control panel, thermostats, etc.) have been completed.
- The phase-neutral connection must be strictly observed, and grounding is mandatory.
After completing the steps described above, the following operations are necessary to start the boiler:
- If the system is equipped with a temperature controller or timer-thermostat, check that they are on.
- Set the room timer-thermostat(s) or temperature controller to the desired temperature.
- Place the main system switch in the "on" position.
- Set the boiler thermostat located on the control panel.
- Place the main switch on the control panel in the "on" position and check that the green indicator light comes on.
The boiler will run the ignition phase, and will remain on until the set temperatures have been reached. If problems occur during ignition or
operation, the boiler will "LOCKOUT," as signaled by the red light on the burner and the red indicator on the control panel. After a "LOC-
KOUT," wait about 30 seconds before resetting the ignition conditions. To reset the ignition conditions, press the burner "button/light" and
wait for the flame to ignite. If this operation fails, it can be repeated a maximum of 2 or 3 times. Then check:
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