| 摘要 |
In a conditioning apparatus unit to be used in relation with conditioning systems of the type having four pipes for the secondary water, wherein the temperature is controlled by varying the secondary air flow passing through two heat-exchangers and a by-pass section by means of valve assemblies, the valve assemblies are actuated by the primary air feeding the same apparatus at a pressure value comprised in the range between 15 and 100 Kg/m2. Each valve assembly relating to a heat-exchanger is operated by an expansion lung fed by the inlet primary air through a valve controlled by a thermostatic device. A linkage mechanically connects the valve assembly of the by-pass section with the valve assemblies of the heat-exchangers in such a manner that when one of the valve assemblies relating to the heat-exchanger is at least partially open, the other valve assembly is locked in the "close" position and only the by-pass valve assembly can be operated by the said one valve assembly. At each position of either of the two heat-exchangers valve assemblies a given position of the by-pass valve assembly is associated and in particular to the "open" position of one of them the by-pass valve is closed. |
