Thermona Therm 28 KD, Руководство по установке

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1.1 Heating mode without weather-compensated regulation
Setting:
The sensor of outside temperature is not connected, the service switch DS2, DS3 – OFF
The operating state of the boiler starts by the switching of the room thermostat (the mode switch in the winter
position). In the case of KDC boilers the relay of the three-way valve is activated and the valve is reset into the
heating position (the starting position of the valve is that of DHW heating, for reasons of time saving). While the
valve is being reset (circa 8 sec), any efforts to ignite the boiler are blocked. In the case of KD and KDZ boilers the
starting position of the three-way valve is into the heating, which means that the above mentioned cycle does not
take place. Then the ventilator is put into operation and the circulation pump and ignition automatics get activated.
The boiler is ignited at the output that was previously set. The set output is preserved for 2 sec from the ignition of
the boiler because of the feedback from the ignition automatics. After that the output gets at the minimum level
with a slow linear rise (circa 1 min) to the point of modulation that is given by the service setting of the maximum
heating output. The output regulation of the boiler in this phase is categorized as the PID type (referring to its
proportion/integration/derivation characteristics) while the temperature set by the revolving knob on the control
panel is maintained in the range of 30 – 80
o
C. If a system with an input lower than the minimum output of the
boiler is heated up, the outlet temperature of the heating water exceeds the set value by 5
o
C. At this moment the
burning in the boiler is stopped, while the circulation pump is still in operation, and the time limit of the repeated
ignition is put into operation (the service setting of the time limit ranges from 0 to 10 min). Given the vast number
of consequently regulated heating systems (e.g. zone regulations, thermostatic valves, etc.), the boiler functions as
an exceedingly adaptable heat source.
When the room thermostat opens, the pump runs down within a settable time (the factory setting is 0 – 10
minutes). This function is used to divert the heat from the condensation device and to balance the temperatures of
different heating elements (useful mainly for horizontal distribution systems) if room thermostats with PI link with
short operating cycles (e.g. Honeywell CM 27, CM 67) are involved.
1.2 Heating mode with weather compensated regulation
Setting: Outside sensor connected, service buttons DS2 – ON, DS3 – OFF
The boiler operates on the same basis as above. The only difference is that the temperature of the heating system
is controlled automatically, depending on the outside temperature which is detected by the outside sensor. The
calculation of the necessary temperature of the heating system is a function of the outside temperature and the
„K“
factor (slope of the weather compensation curve). The factor is set by the service technician according to the
natural environment of the premises and the type of the heating system. Use the adjusting revolving knob on the
control panel to set the required temperature of the heating system (correction of the offset of the weather-
compensation curve is in the range of
±
15 °C).
The weather compensation curve is calculated for the standard heating system with radiators.
Curve graphs
Slopes of the weather-compensation curve Off-sets of the weather-compensation curve
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