| 摘要 |
An adapter fitting for the selective connection of a heater to a single or double-tube heating installation has a housing (2) in which there are two channels (3, 4) through which the heating medium is taken during operation from the heating installation to the heater or from the latter. In each of these channels there is a shut-off valve (26 or 27). In addition there is a connecting channel (5) connecting the two channels (3, 4) in which there is a regulating and shut-off valve (29). The two shut-off valves (26, 27) have closing components (24, 25) operating in a straight line and in a common plane bounded by the axes of the two connectors (10, 11) by which the fitting is connected to the heater. A closable drain aperture (34) opens into the atmosphere from at least one of these connectors (10, 11) for the purposes of emptying the heater when the shut-off valves (26, 27) are closed without interfering with the operation of the rest of the installation. To this end the two shut-off valves (26, 27) can be operated independently of the regulating and shut-off valve (29), and the drain aperture (34) can also be closed independently of these valves. |
