
1.6. SAFETY ELEMENTS
1.7. FUEL
Safety elements, fuel
Only wood pellets are used as fuel in PelTec / PelTec-lambda. Wooden pellets are bio-fuel made of
wooden wastes. Pellets can be packed in different packaging: in bags (15 kg or 1000 kg), or as bulk in
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large (underground) tanks ( 4 - 15 m ) or in basement spaces. Pellets used in pellet boiler must be in
accordance with following norms: ENplusA1, DINplus, ONorm-M-7135 or DIN 51731.
Recommended properties of pellets are following:
- heating value >= 5 kWh/kg (18 MJ/kg)
- diameter <= 6 mm
- max. lenght = 50 mm
- max. moisture content <= 12 %
- max. dust content <= 1,5 %.
Boiler have a few safety elements:
- Bimetal thermostat - built on the burner pellet feeding tube. If the bimetal set temperature (80°C) is
exceeded, pellet feeding is stopped, the boiler stops working and the E8, E8-1 or E8-2 and "Pellet
supply tube temperature too high" are displayed on the controller screen.
- Pressure switch - if there is no underpressure in the boiler (eg. chimney is not passable, any boiler
door or cleaning opening is open or the PVC pellet supply pipe is punctured), the controller displayed
E12 and "Safety pressure switch", and the boiler stops working.
- Photocell - in case there is no flame (photocell does not see flame) in the ignition phase at the set
time, the controller displays E18 and "No flame in ignition stage" and stops the boiler, if the flame
disappears in the ignition phase, the control displays E23 and "Flame disappeared in ignition stage"
and stops the operation of the boiler, if the flame disappears in the stabilization phases, the controller
displays E24 and "Flame disappeared stabilization stage" and stops the boiler, and if the flame
disappears in the phases of boiler operation, the controller displays E19 and "Flame disappeared
working phase" and stops the boiler operation.
- Controller has a built in protective function which protects the boiler against overheating. If
temperature in the boiler exceeds 93 °C, regardless heating or sanitary water is needed the boiler
pump and/or the sanitary water turns on and works until temperature in the boiler falls below 93 °C.
- The fan has a built-in RPM counter and, if regulation is informed that the fan does not operate in
accordance with the requirement interrupts the process display error E13 and "Fan error"
- The grate cleaning mechanism has two built-in microswitches that monitor the position of the grate.
If the grate is not in the required position at a certain moment, the controller receives this information
and interrupts the operation process, and E21 and "Error grate cleaner" will appear on the display.
- Flue gas connection have in-built sensor for flue gas temperature meassuring. If flue gas tube
temperature is over 300 °C, controller interrupt proces and display information E4 and "Flue gas
sensor error»
- STB thermostat - When temperature in the boiler exceeds 110°C (+0°C / - 9°C), power supply is
turned off by the safety thermostat (STB).
- Thermal protection (built in coils of the fan electric motor at the burner and the screw feeder motor,
flue pipe cleaning, grate cleaning) protects them against overheating caused by failure or locking.
- Flexible PVC tube connecting the pellet burner and pellet tank is made of plastic material reinforced
with metal wire which, in case of back flame from the burner to the tank, melts and prevents flame to
penetrate to the pellet tank.
- PelTec-lambda 69 and 96 have build in thermal protection exchanger. Thermal protection valve
must be installed to it and connected to the water suppy to provide boiler cooling in case of
overheating (thermal protection valve is in standard delivery, Caleffi 543, 98°C ).
16 Technical instructions PelTec-lambda