Protherm Gepard 23 MOV, Training Manual, Page: 46 / 68

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T e c h n i c a l T r a i n i n g
Service visit :
List of recommended annual checks:
Components Check Method
Domestic hot water
flow rate sensor Ignition of the burner for a
domestic hot water flow rate
of 1.5l/min
In the installer menu, line d36 indicates the domestic hot water
flow rate.
- Check that the burner properly ignites at the expected flow
rate.
- Check that the flow rate measured corresponds to reality.
Gas valve Does the gas flow rate
modulate correctly?
Draw off water at max. flow rate
Reduce the draw rate until the burner goes off.
Check that the gas flow rate follows.
NTC Thermistors Measure the resistance of
each thermistor (12,500Ω at
20°C, 1,750Ω at 70°C)
Disconnect the thermistors to measure the resistance.
Flame detection
(ionisation): Ionisation quality The ionisation quality can be checked with data item d44 of the
After-Sales menu:
Less than 300 with the burner lit = good detection
Temperature
regulation Does the burner shut off at
the end of regulation? Check that the burner shuts off when it approaches the setting
(test to be performed in hot water mode at low flow rate)
Pressure sensor Does the sensor stop the
boiler if the pressure drops
below 0.3 bar?
If possible, close the heating circuit isolation valves and drain
the boiler until it shuts off.
Expansion tank Does the tank still contain
gas? Check that the water pressure remains stable in operation.
If not, check the tank pressure when empty.
Also check:
- Check that there are no water leaks (at connections, safety valves, disconnect... )
- Check that there are no gas leaks (at connections, gas valve...)
- the sealing of the exhaust ducts
- the electrical ground connections
Clean:
- the burner
- the main heat exchanger
- the fan
- the heating filter (if necessary, clean the installation)
- domestic hot water filter
The seals must be replaced each time they are removed.