Special Maintenance; Cleaning The Boiler; Checking Boiler Operation - Ferroli PREXTHERM RSH 950N Instruction For Use, Installation And Assembly

- Gas boilers: Once a year
- Gas oil boilers: Twice a year
In any case, local maintenance standards must be observed.
During routine maintenance, remove the turbulators and then brush the tube bundle and furnace. Remove the deposits accumulated in the
smoke box through the open inspection doors. For more thorough cleaning, remove the rear smoke box. If worn, replace the flue gas seal.
Check that the condensate drain is not blocked. Make sure the control and measurement devices on the boiler are working correctly.
On this occasion, record the amount of top-off water used. After analyzing the water, perform a preventive descaling.
After repeated fills, the calcium and magnesium salts dissolved in the water will produce deposits in the boiler, cause the metal plates to over-
heat, and may cause damage that is not attributable to materials or workmanship, and is therefore not covered by the warranty. After performing
cleaning and maintenance operations and the next ignition, check the tightness of the door and smoke box. In the event of combustion leaks,
replace the corresponding gasket.
The operations performed must be recorded in the system logbook.

7.3 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 hermet-
ically 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.

7.4 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 smoke box 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.

7.5 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.
36
EN
2 3 1
fig. 15
cod. A73020821 - 2023-09
PREXTHERM RSH N
6
fig. 16
5
4