Some hydronic heating systems use electrically operated valves to control the flow of water into each zone. In these zoned hydronic systems, the valves operate…
Category: Steam and Hydronic Line
A flow control valve is used (1) to prevent gravity circulation in a hydronic heating system when the circulator is not operating and (2) to…
A hot-water heating control consists of an outdoor liquid expansion type bulb connected by a capillary system to a double-ported three-way automatic mixing valve (see…
Water-tempering valves are used in hot-water space heating systems where it is necessary to supply a domestic hot-water supply at temperatures considerably lower than those…
An electric control valve (regulator) is designed to provide remote electric on-off control in heating systems and steam process applications (see Figure 10-49). The solenoid…
Temperature regulators are used for many heating and cooling applications, including small-flow instantaneous heaters or coolers (shell-and-tube or shell-and-coil heat exchangers), small storage or tank…
Sometimes air pockets will form in the pipelines of steam or hot water heating and cooling systems and retard circulation. One method of eliminating these…
An undersized expansion tank or one that is completely filled up with water will cause the boiler pressure to increase when the water heats. Because…
The air in a diaphragm-type expansion tank is separated from the water by a flexible rubber membrane (see Figure 10-44). These tanks are smaller than…
The closed steel expansion tank has no moving parts (see Figure 10-43). It is normally two-thirds filled with water and one-third with air. As heated…