DeDietrich 310 ECO Series, Installation And Operating Manual, Page: 60 / 76

59
De Dietrich Gas 310/610 ECO
14.4 Failure (lock-out) codes (requires user intervention, manual reset of control)
When a failure code is displayed, both the code window and the

window will flash alternately. Except for
failure

(does not flash).
Failure Description Cause/check points

Flame simulation,
(flame detected in the off position)
- Burner glows as a result of high CO
2
percentage (> 10% CO
2
)
- Check ignition/ionization electrode gap 1/8" or [3-4mm]
Gas valve is leaking or is stuck open, check and replace

Short Circuit in 24v circuit
Check;
- Wiring to sensors
- Wiring to gas valve

No flame or ionization signal after 5
attempts
a) N° ignition spark, Check;
- Connection of ignition cable and spark plug cover
- Ignition cable and electrode for breakdown
- For 'flash over' between spark plug cover and earth
- Electrode distance, should be 1/8" or 3.5mm
- Condition of burner set (burner set / electrode seal) earth
b) Ignition spark is present, but no flame. Check;
- The gas main cock valve is open
- There is sufficient inlet gas pressure > 3,5 "w.c. [8.7 mbar]
- The gas pipe has been purge of air
- The gas valve multiblock is energized, during ignition
- The electrode is clean and fitted correctly
- The gas pip is not blocked or fitting correctly
- The air supply or flue gas discharge is not blocked/fitted incorrectly
- The gas/air mixture is set correctly
c) There is flame, but there is insufficient ionization < 2µA, Check;
- The condition of the electrode and earth
- The temperature sensors for leakage current
 Gas valve multiblock defective
Control unit does not recognize gas valve multiblock, check;
- The wiring on the gas valve has been disconnected or not fitted
- The gas valve is not defective (burned °out or short-circuit)
 Fuse 3 blown Replace fuse 3
 Permanently locked out
Mains voltage has been disconnected during lock out, solution; reset (original lock-
out usually return automatically)

No processor handshake (or external
influences)
Fault in control unit or fault due to EMC influences, Reset first if fault persists,
replace control unit. If fault still persists, locate and remove possible external EMC
sources
 Input failure; sensors are short circuiting
Check the wiring of the temperature sensors. If fault persists, replace control unit. If
fault still persists, locate and remove possible EMC sources.

Gas valve multiblock relay fault Gas valve multiblock defective or not connected.

Air pressure differential sensor does not
maintain check level
Check;


Air pressure differential sensor does not
maintain check level
- The air supply or flue gas discharge for blockages/ installation faults.
- The air pressure differential switch and connections

Fault on internal communication bus
(I
2
C-bus) when reading EPROM
Check
- The multiple wire cable in the instrument panel for short circuit
- Moisture on the display
- Find and remove and EMC sources

Locked input open (external safety
controls) LWCO & Hi Limit
- Maximum thermostat (=external protection), connected to terminals X29.1 & 29.2
on the terminal strip, has tripped or jumper has been removed.
- Fuse F3 on automatic burner unit is defective
 Gas multiblock protection Gas valve multiblock defective or not connected.
 Flow temperature too high
Check;
- Flow
- System as has proper air elimination
- Temperature sensors for deviations
- Water pressure in the system
 Excessive fan speed
Check;
- Fan setting parameters
- Fan cable is defective or poor connection, if failure persist fan or control unit may
be defective.