Pelltech PV20a - Principal Function; Safety Devices

PV20a / PV30a pellet burner
page 8/ 41
DK9902A1 www.pelltech.eu
6. User interface screen
2-row screen to display burner status and to change its settings.
7. Battery
Enables to empty feeder auger and finish burning pellets in
burning chamber when mains power is lost (blackout) or safety
thermostat has turned burner off. It takes approx. 30 minutes.
8. Sockets
For connecting the mains supply, boilers thermostate and
external auger.
9. Feeder auger motor
Rotates internal feeder in order to transport pellets to burning
chamber.
10. Fan
Blows air to burning chamber according to actual burner power
level.
11. Fuel level sensor
Optical sensor, what starts external auger. Sensor consists of
sender – receiver pair.
12. Mounting nut
M6 nut connects burning chamber to burner housing
13. Flame sensor
Optical sensor to detect flame in burning chamber.
14. Igniter
Electrical heating element what heats up the air and ignits
pellets.
15. Grate
16. Safety thermostat
Grate with air supply holes made of heat resistant 4mm steel
253MA on what pellets burn.
Turns off the mains and external auger, when feeder augers
temperature rises above limit. It is a safety measure against back-
burning.
Principal function 1.1
The PV20a/30a burners are meant to be installed in a boiler and fuelled with wood pellets. The external
auger transports the pellets from a pellet container to the burner. The controller board contains a
microprocessor system that tests main safety components, monitors and regulates the burning
procedure, starts and stops the burner automatically according to the boiler temperature. A warm air
element (electrical igniter) ignites the pellets. The start procedure is designed to create a quick and
smoke free ignition.
The burner starts burning when the boiler temperature cools down and boilers thermostat switches on.
Burner runs until the pre-set maximum boiler temperature (switch-off temperature) has been reached.
After that burner stops safely burning procedure and goes to waiting (stand by) status.
Main supply interruptions (blackouts) are taken care of by the control system. After a main supply
interruption burner stops safely burning and goes to stopped status.
If there is a safety risk, the burner switches off.
Safety devices 1.2
The burner has following safety devices (Figure 2) against back-burning and other dangerous situations.
1. Melting hose
2. Temperature sensor
3. Controller
4. Back up battery
5. Safety thermostat