Open expansion tank installation kit, no sanitary water, coupled with gas boiler.
In this the second pump kit is sold separately.
With this kit the water circulating in the Thermo fireplace does not mix with the boiler, thus isolating the Thermo fireplace from the plant.
The recommended schedule is shown in the diagram. The kit is supplied as shown on the picture and contains the parts inside the blue box of the diagram; includes electronic control unit.