Termal Kamin 20, Service Manual

Page: 7 / 99

Service manual
7
2.1.6 Thermostat
The thermostat is a safety switch for the temperature of the liquid in the boiler. It performs the function
of protecting the device (boiler / fireplace), the central heating system or people and objects that are
located close to the boiler and heating installation due to overheating and the formation of a fire when
the boiler temperature is exceeded. The factory thermostat is set to activate contacts at the maximum
operating temperature of the device (fireplace / boiler) of 105
o
C. The probe thermostat is inserted
together with the NTC temperature sensor in the copper coil located in the boiler body. The built-in
thermostat has a bistable characteristic, ie. once the thermostat is activated due to temperature
overrun, it remains active even when the temperature of the device falls. In this regard, when the cause
of overheating of the boiler is eliminated, the thermostat must be manually reset by pressing the small
pin located below the black protective cap most often on the back of the boiler.
x
Airflow sensor so-called "delta"
The air flow sensor bases its work on measuring the pressure difference in front and behind the
diaphragm on the suction line of the boiler. The sensor itself is located directly on the control unit and is
connected with the diaphragm using two silicone hoses for Pa + and Pa-. Based on the obtained
measurement results, the control unit optimizes the combustion process in a way that controls the
speed of the suction and exhaust fans.
Pa+
Pa-