English
10
A.O. Smith Dscale
s
Appliances with a cleaning
opening
1. Switch the appliance off, following the instructions in the equipment manual.
2. Drain the appliance (see equipment manual).
3. Remove the cleaning opening's cover plate
1
on the outer jacket.
See
.
4. Undo the bolts.
5. Remove the cover and the gasket.
6. Flush the appliance with tap water to remove loose impurities.
7. Close the drain valve.
8. Remove loose scale deposits manually.
9. Where the scale deposits cannot be removed by hand, use A.O. Smith
DScale.
Warning
Wear safety goggles and rubber gloves. A.O. Smith DScale irritates the skin
and can cause serious eye injuries.
10. Add the appropriate number of litres of A.O. Smith DScale, as described in
.
11. Dilute the DScale with the same number of litres of water.
n
Note
For severe scaling, use double the quantity of DScale undiluted. When there
is not much scaling, dilute the DScale in the proportions 1:2. The total
quantity of liquid must always match the figure given in
.
12. Leave the mixture in the appliance for 1 to 2 hours, depending on the
amount of scale. DScale works for up to 2 hours. The effect decreases
gradually.
13. Open the drain valve.
14. Open the filler tap slowly and flush the device thoroughly with tap water.
Rinsing is required because DScale is acidic.
15. Look in the cleaning opening and check whether all the limescale deposits
have been removed. If not, repeat the descaling procedure.
16. Close the cleaning opening. Tighten the bolts to a torque not exceeding
50Nm (to prevent damage to the tank). Use suitable tools. When tightening
the bolts, use the sequence shown in
n
Note
You must replace the gaskets and fixings regularly so that a watertight seal
can be guaranteed for the cleaning opening. You can obtain a special set for
this from A.O. Smith.
Figure 4
Example of an opening
allowing cleaning
IMD-0080
1
SU
Figure 5
Bolt tightening
sequence
1
3
6
2
4
5
