Oversink and Undersink Water Heater
- 17-
MALFUNCTIONS
POSSIBLE CAUSE
SOLUTION AND EXPLANATIONS
Indicator light does not
come on (hot water comes
out)
Lamp not connected
Reconnect the lamp and thermostat.
Faulty lamp
Replace lamp
Indicator light does not
come on
(hot water does not come
out)
No current
Reinstate the mains power supply
Thermostat safety limiting
device tripped
Reset the thermostat. Call qualified personnel. See notes
on “Safety limiting device”
Indicator light always on
(with little hot water
available)
Drawing tap/s open
Check and close any hot water drawing taps even left
partially open.
Leak in system hot water
section
Have a qualified plumber check the plumbing system; a
small leak can activate the heating element often or
continuously.
Indicator light always on
(hot water does not come
out)
Thermostat connectors not
correctly inserted in heating
element
Remove the thermostat and check the connectors
(thermostat and heating element). Call qualified personnel.
Heating element interrupted
Check electrical continuity and insulation and replace the
heating element if necessary. Call qualified personnel.
Indicator light goes off
when water heater is
switched on
Element line overloaded or
heating element earthed
causing tripping of
protection device
Disconnect any other electrical appliances or call qualified
personnel to replace the heating element
Electric heating element
noisy
Anomalous level of water
hardness.
Water causing scaling.
Scale on the heating element causes an uneven and
violent heat exchange in the places where it has come off.
The definitive solution is to install a water softener (A
dispenser may not be sufficient).
Dripping from water safety
unit
Internal pressure greater than
or equal to 0.7 Mpa (7 bar).
(Often due to normal water
expansion during heating)
The system cannot “absorb” the water expansion in
heating. To avoid dripping install an expansion tank or
connect the safety valve to a drain.
See the relevant section “Dripping from water safety unit”
and “Expansion tank”.
Water leaks
GENERAL NOTES
Leaks are generally seen at the bottom of the appliance.
Condensation
Dripping can occur if the water in the tank is cold. Always
check for leaks with the water hot.
Hot and cold water flexible
connectors
Check tightness and replace the gaskets.
Tighten down and check tightness
Leaks from heating element
Check tightness, replace gasket and tighten securely.
Replace the heating element if faulty.
7.9
General notes
Always use tools that are appropriate for the intended purpose.
Always replace the gaskets and/or the o-rings ensuring the hydraulic sealing.
Only use genuine spare parts.
During reinstalling make sure that:
the electric heating element is properly housed and the sealing gaskets are correctly installed;
the safety and regulation devices (thermostats) are properly installed inside their housings;
before reconnecting the equipment to the mains fill it (referring to the appropriate section) and check that there
are no water leaks.
