Most Frequent Function Failures And Their Causes - Drazice OKCE 80 Operating And Installation Manual

If water contains too many minerals, an expert has to come to remove the scale that forms inside
the tank, as well as free sediments. This has to be performed after one or two years of operation.
The cleaning is carried out through the hole in the flange - dismantle the flange lid and clean
the tank. A new sealing has to be used for re-fitting. Since the inside of the heater has special
enamel, which must not get in contact with the scale removing agent - do not work with a lime
pump. Remove the lime layer with a timber and suck it off, or wipe it off with a clout. After that,
the appliance must be rinsed thoroughly and the heating process is checked the same as during
the initial putting in operation. Do not use any abrasive cleaning agents (such as liquid sand,
chemicals - acid, alkaline) or dye thinners (such as cellulose thinner, trichlor, and the like)
to clean the outer shell of the heater. For cleaning use a wet clout and add a few drops of liquid
cleaning agent for household applications. Repeated heating causes lime scale settling
on the receptacle walls and mostly on the lid of the flange. Lime scale settling depends
on hardness of heated water, its temperature and on the volume of hot water used.
We recommend checking and cleaning the tank from scale and eventual replacement of the
anode rod after two years of operation. The anode life is theoretically calculated for two years
of operation; however, it changes with water hardness and chemical composition in the place
of use. Based on such an inspection, the next term of anode rod exchange may be determined.
If the anode is only blocked with sediments clean its surface and, if used up, mount a new one.
Have a company in charge of service affairs deal with the cleaning and exchanging of the anode.
When draining water from the heater, the combination faucet valve for hot water must be open,
preventing occurrence of under-pressure in the heater tank which would stop the water
from draining.

2.9 MOST FREQUENT FUNCTION FAILURES AND THEIR CAUSES

FAILURE SYMPTOM
Water is cold
Water is cold
Water is not warm enough
Temperature of water is
not corresponding with
the temperature set on
the control
Water is constantly
dripping off the safety
valve
INDICATOR
•
Light on
•
Light off
• Light on
•
Light off
Table 5
SOLUTION
• The temperature set on the
thermostat is too low; heating
element failure
•
No supply voltage!
•
Thermostat failure
•
Safety thermostat shut off
probably due to failed
operation thermostat
•
Failure of one of the coils
in the element (3x 1350 W)
•
Defective thermostat
• high input pressure
•
defective safety valve
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