Water-Side Maintenance; Descale The Tank - A.O. Smith SGS-28 Installation, User And Service Manual

10.2
10.2.1
92
The display will now show INTERNAL CHECK for about 10 seconds, and will then go
to the main menu.
7. Activate ON mode by going through the following steps:
-
Press once on the blue arrow [ ] to position the cursor beside ON, then press
[ENTER].
- Confirm the selection START OPERATION with [ENTER].
8. If there is no heat demand, then raise T
setting. Draw some hot water off to create heat demand.
9. Check whether the heating cycle runs correctly (see section 4.1.1).
10. If you have adjusted T
11. Remove the plastic cover on the top of the appliance.
12. Check the supply and burner pressures (see section 7.9.2) and adjust them where
necessary.
13. Check that all components of the chimney flue system are properly attached.
14. Check the pressure differential across the pressure switch (see section 7.9.5) and, if
this is too low, the heat exchanger should be cleaned (see section 10.3.2).
15. Test the operation of the overflow valve of the protected cold supply setup. The
water should spurt out.
16. Check the drainage pipes from the discharge points of all valves and remove any
scale deposits that may be present.
17. Drain the water heater, see draining (see section 7.10.2).

Water-side maintenance

To do water side maintenance:
• Descale the tank (see section 10.2.1)
• Clean the condensate drain (see section 10.2.2)

Descale the tank

Scale and lime build-up prevent effective conduction of the heat to the water. Periodic
cleaning and descaling prevents build-up of these deposits. This increases the service life
of the water heater, and also improves the heating process.
Take the rate of scale formation into account when deciding on the service interval. Scale
formation depends on the local water composition, the water consumption and the water
temperature setting. A water temperature setting of maximum 60°C is recommended for
the prevention of excessive scale build-up.
To guarantee a good, watertight seal around the cleaning opening, replace the gasket,
washers, bolts and, if necessary, the lid with new parts before reassembly (see the figure).
A special set is obtainable from the supplier/manufacturer.
To simplify descaling and cleaning of the tank, the water heater is equipped with two
cleaning openings.
. (see section 4.3.3) Note the original
set
, return it to the original value (see section 4.3.3).
set
Installation, Maintenance and Service part