Unical AIREX 25 2S, Installation And Servicing Manual

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Instructions for the installer
3.12 - STANDARD CONTROL PANE
The standard control panel (code 36749) operates in a semi-automatic way and is supplied in a cardboard with the following
standard items:
- Microswitch which has to be fitted to the mechanism controlling the bypass rod (TKS) as shown in fig. 14 page 17.
- A 3 pole cable for the fan’s electrical connection (2 fans for the models AIREX 65 2S and AIREX 80 2S)
The connection of the thermostat bulbs to the bulb holders must be carried out as shown in fig. 16, on page 18.
The connection of the loads to the control panel (C.H. pump, recirculation pump, fan, etc.) must be carried out according
to the general wiring diagram in fig. 21 and/or according to the practical wiring diagrams on page 24 and 25.
Functional description
Once the main switch pos. 11 and the pump switch pos. 13 are in the ON position, it is possible to light the boiler.
Once the boiler has been fired, close the loading door; in this way the TKS microswitch, operated directly by the rod closing the
smokes bypass to the chimney, will reset the temporized relay that “will begin to count.”
The factory adjusted time of the temporized relay is of 30 minutes, which can be extended to an additional 30 minutes.
The
Tsc thermostat (minimum thermostat) is not satisfied at boiler start-up, because adjusted at 65°C, actually prevents the
C.H. pump running, until this temperature is reached.
If the boiler does not reach the 65°C in the set time, the temporized relay stops the fan.
This can be due to the boiler not firing or due to an insufficient load of the firewood.
To avoid this inconvenience it is possible to increase the temporized relay’s intervention time (this operation has to be done only
by trained personnel) or more firewood has to be loaded.
If the boiler fires in a regular manner, when the boiler reaches 65°C the C.H. pump is activated.
The working thermostat, pos. 32, acting on the fan(s) operation mode, will make the boiler fire in an “automatic” way.
The same thermostat will stop the fan when the preset working temperature has been reached.
In case of boiler overheating (temperature higher than 90°C), and in case of the delayed intervention of the heat relief valve
(remember that in solid fuel boilers, due to high thermal inertia, the installation of this valve is compulsory), the maximum
thermostat
Tmax , bypassing the microswitch TKS , the C.H. pump’s thermostatic control Tsc and the pump switch Ipi , will
automatically allow the boiler thermal inertia to discharge into the central heating circuit. This situation could cause an undesired
heating of the radiators, even if the ambient temperature does not request it.
On the fan’s electrical supply there is a safety thermostat Ts that will switch OFF the fan in case
A temperature of 100°C is reached (safety limit temperature).
It is possible to reset this thermostat by unscrewing the cap in pos. 31 and pressing the button underneath.
A room thermostat can be connected on the terminals 19 and 20 after having removed the jumper that links them.
The recirculation pump
Pr has to be connected to the terminals 10 and 11.