28
The acid solution specified in the table is sufficient to remove a thickness of about 2 mm. of scale along the
whole coil.
6) The closed-cycle operation should last for at least 2-3 hours and in any case until the formation of foam is
seen in the container.
N.B. If there is considerable scaling, the operation should be repeated completely, renewing the solution
once the time mentioned above has elapsed
7) When the operation is finished empty the coil and the container completely.
Collect the solution and neutralise it before draining.
Wash the coil and the container with clean water under pressure, then drain again.
8) In the normal container prepare a neutralised alkaline solution with water and sodium bicarbonate (Solvay
Soda) base in the proportion specified in the table.
9) Circulate the solution in the coil for about 30’ then drain.
This operation would be better performed hot (60–70 °C), lighting the burner from time to time.
10) Cool, drain and wash carefully to remove the operation residues from: valves, dischargers, etc. Reas-
semble the previously removed filter meshes, replace the piping and start the boiler.
UNI-MATIC
UM model
Tank capac.
(minimum).
L
Water
content
L
Acid
content
L
Cont. Inhib.
“Lithsolvent”
L
Content
“ solvay
soda”
kg
UM 30
100
80
11
0.50
3
UM 50
150
120
16
0.75
4
UM 100
200
160
22
1
6
UM150,
UM 200
300
200
30
1.5
10
UM 300
500
300
40
2
15
Important: in order to operate in security we recommend to ask to our assistance contacting
Bono Energia
S.p.a. (+39 02 55302848).
DOWNTIME
When the generator is placed out of operation for a short time there are no particular precautions; in the case
of long downtime the generator should be set up to avoid deterioration to the coil and the equipment.
•
Clean the smoke side of the generator carefully by washing with water and caustic soda.
•
Immediately afterwards start the generator again for a short time to remove the humidity completely.
•
Discharge the coil under pressure and then leave the generator to cool.
•
In a separate container prepare an alkaline water solution with 50% sodium bicarbonate “Solvay Soda”
(see tab. 7)
•
Fill the coil completely and fill the water supply circuit up to the on-off valve on the pump suction, with the
alkaline solution described above.
•
Close all the generator valves.
•
Put a blank on-off flange between the generator and the chimney.
•
Lubricate the valve closing screws and all the generator bolts and stud bolts.
•
Protect the control panel and all the equipment against dust and external humidity.
N.B. To protect the coil avoid the dangers of frost.
8. MAINTENANCE
Table 7
Chemical descaling standard data
