Types of Gas Burners

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Types of Gas Burners

Types of residential gas burners include atmospheric injection, yellow (luminous) flame, and power burner units. Their classification is determined by the firing method used. Gas burners can also be divided into two broad classifications based on whether they are specifically designed as integral parts of gas-fired heating equipment, as in Figure 2-4, or are used …

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ACL FP Programmers

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ACL FP Programmers

(a) Fully pumped 2 x 2 port motor open/close valves links 4–9, 5–7 (b) Fully pumped 2 x 2 port spring return valves, 1 x 3-way mid-position valve, Satchell Duoflow Switchmaster Midi and Drayton Flowshare link 1–4–9 and 5–7 (c) Tower or ACL Biflo mid-position valve link 1–4–9 (d) Terminal 3 is a spare terminal …

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Electric Zone Valve

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Electric Zone Valve

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 in conjunction with a single circulator. The construction details of a typical electric zone valve are illustrated in Figure 10-62. When the room thermostat calls for heat, an electrical current …

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Flow Control Valve

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Flow Control Valve

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 permit the summer–winter operation of an indirect water heater. As shown in Figure 10-61, a flow control valve can be installed in either a vertical or horizontal position. Either location …

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Hot-Water Heating Control

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Hot-Water Heating Control

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 Figure 10-59). It is designed to blend the hot water from the boiler with the cooler return water in inverse proportion to the outside water and deliver the blended water …

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Water-Tempering Valves

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Water-Tempering Valves

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 of the water in the supply mains. The water-tempering valve automatically mixes hot and cold water to a desired temperature, thus preventing scalding at the fixtures. These valves are designed …

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Electric Control Valves

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Electric Control Valves

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 pilot at the top of the valve is connected to a room thermostat, automatic time clock, or some similar device from which it can receive an electrical signal. When the …

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Temperature Regulators

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Temperature Regulators

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 heaters, and similar installations. The Spirax Sarco Type 25T temperature regulator shown in Figure 10-48 is a diaphragm-operated valve used for regulating temperature in a variety of different process applications. …

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Air Eliminators

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Air Eliminators

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 air pockets is to install one or more air eliminators at suitable locations in the pipeline. An air eliminator (or air vent) is a device designed to permit automatic venting …

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Troubleshooting Expansion Tanks

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Troubleshooting Expansion Tanks

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 expansion tank is too small or too filled with water to absorb the excess pressure, the relief valve will begin to drip. The dripping relief valve is only symptomatic …

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