A.O. Smith 120 through 250 Series - Manual (Page 88)

Performing maintenance
88 Instruction manual BFC
15
s
4. Inspect the tank and remove the loose scale deposits and contamination.
5. If the scale cannot be removed by hand, then the appliance will need to be
descaled using a descaling agent. Contact the supplier for advice on the
preferred descaling agent.
6. Close the cleaning opening. To avoid damage to the tank, tighten the bolts
that fasten the lid with a torque no greater than 50 Nm. Use suitable tools for
this.
15.3.4 Cleaning condensation water discharge
Regular cleaning of the condensation drain and siphon is essential for
prevention of blockages.
15.4 Gas-side mainte-
nance
15.4.1 Introduction
The following steps must be carried out on the gas side:
1.
Clean the burner(s) .
2. Clean the orifice(s) .
3. Cleaning the heat exchanger .
4. Finalizing maintenance .
15.4.2 Clean the burner(s)
1. Detach the burner(s)
2. Remove all contamination present on the burner(s).
3. Fit the burner(s)
15.4.3 Clean the orifice(s)
1. Detach the orifice(s)
2. Remove all contamination present in the orifice(s).
3. Fit the orifice(s)
15.4.4 Cleaning the heat exchanger
1. Detach the burner.
2. Clean the combustion chamber of the heat exchanger using a vacuum
cleaner and a soft brush.
3. Detach the flue gas discharge.
4. Clean the end of the heat exchanger using tap water.
5. Fit the burner.
6. Fit the flue gas discharge.
Note
Check the pressure differential again after cleaning. If the pressure
difference is too low following cleaning, please contact the supplier of the
appliance.
15.5 Finalizing mainte-
nance
To finalize the maintenance carry out the following steps:
1. Fill the appliance
(5 "Filling") .
2. Start the appliance (9 "Starting and running") .
3. Erase the message SERVICE REQUIRED. Do this by pressing once on
then once on .