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3. Burning
3.1. Controller - description, operation and maintenance
Boiler automatic control unit utilizes a microprocessor-controlled PLUM
ecoMAX 200 controller. Its task is to maintain the preset temperature in the
heating circuit and temperature of hot water in hot household water reservoir.
Regulation may be performed using any of the three available methods:
employing linear reduction of air supply rate when the boiler is nearing its
set temperature (CLASSIC regulation method)
by continuous modulation of the air supply (PID control, without
combustion gases sensor),
by continuous modulation of the air supply (PID control, with combustion
gases sensor, which is a part of the boiler's standard equipment)
Inclusion of the combustion gases sensor with the boiler has significantly
contributed to reduction of chimney stack losses. It also allows to detect very
fast nearing out-of-fuel condition. This reduces thermal losses related to the
fuel-less fan operation and extends the boiler readiness for fuel refilling. The
user does not have to hurry with fuel refilling, as fast detection of the out-of-fuel
condition will maintain heat in the boiler for longer periods. The optimum
temperature of combustion gases set in the regulator shall lie within the range of
200 to 230
O
C. A higher temperature would contribute to increased chimney
losses - a lower temperature may lead to water condensation in rear chambers of
the boiler, which would affect its durability.
Fig. 9 Control system with ecoMAX 200 controller – front view
1. STB temperature limiter
2. Control light (red)
3. Settings buttons
4. ecoMAX 200 regulator control panel
2
4
6
7
5
5. Display
6. Power switch
7. Fuse
8. Thermo-manometer
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1
P
T
3