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Chapter 4 Water Supp
Chapter 4
| Question | Answer |
|---|---|
| Hot water is water to which heat ? | Heat energy has been added |
| Domestic Hot water Temp should be between? | 105F and 140 F |
| When water is heated it? | Expands and volume decrease? |
| Temperature and pressure relief valve | A dual type safety valve |
| As water is heated it immediately starts to____ | expand |
| A thermal expansion tank features a _____ air cushion ___ to the minimum system pressure before recovery starts | sealed, precharged |
| The volume of hot water supply is governed by recovery rate of hot water heater | True |
| Specific heat is the amount of of heat required to raise temperature of 1lb of a substance____ | 1F |
| The definition of specific heat indicates you must know the _______ of the water to be heated. | weight |
| Water can be heated using _____ and ___ | Direct and Indirect |
| whats Four direct methods for heating domestic hot water? | Gas,, Oil, Electricity, Instantaneous |
| Point of use heaters are small fixture____ type water heaters | under storage |
| Heat is a form of_____ that produces work or motion | Energy |
| What s convection associated with? | Liquid and Vapors |
| Water weight is 8.33LB | True |
| Gas fired heaters have____ burners forced draft burners_____ burners | atmospheric and condensing |
| Heating elements in electric water heaters are available in variety of____ and ___ | Voltages and Wattages |
| What is most common lining applied to interior of water heater tanks made out of? | Glass |
| Magnesium ___ are used used to protect the interior surfaces of a steel tank | Anode |
| Domestic Hot Water supply systems can be best classified by the type of service they perform, that is one temperature and____ multiple | multiple |
| Forced____ requires the use of a circulating or booster pump | circulation |
| What are check valves? | They are used to prevent backflow and back pressure in hot water supply |
| Expansion of water in a hot water supply system also causes the pipe which carries the water to expand as as heat is _______ | Transferred |
| Mechanical_______ joints or _____ joints can be used to absorb expansion in a hot water supply. | Expansion joints or Swing joints |
| Food service applications are most common examples of_____ temperature hot water supply systems. | multiple |
| Whats the minimum temperature needed for commercial dishwater sanitizing rinse is | 180F |
| What are the major parts of hot water supply system? | Mains, Risers, Major Branch, Minor Branch, Circulating Lines, Terminal Points |
| One temperature systems are often called______ | Recovery systems |
| Food service applications are most common examples of_____ temperature hot water supply systems. | multiple |
| Gravity circulation is more important than forced circulation? | False |
| A____ control valve is used in a hydronic heating system to prevent circulation of hot water when hot boiler water is not need. | Flow |
| The horziontal pipe between an ATFL fitting must pitch up at least ______ | 1" |
| What must be used if a dip tube cant be used | in line air seperator |
| Centrifugal pumps can be install where? | supply and return piping |
| How is a electronic zone valve operated? | It is electronically operated |
| A closed hot water heating system holds a solid fill of water in the? | a) expansion tank b)boiler,piping, radiation c)flow valve D)circulating pump |
| All piping in a hot water system must be ____ so that air in system can be____ into the expansion tank or from manual air vents | pitch, vented |
| Which fittings should be used when changing size of horizontal runs of pipe | eccentric fittings |
| A draft hood must be attached directly to a gas | fire water heater |
| An immersion type aquastat device does what? | Sense the temperature of water being heated |
| The basic deigns of water heaters are intended for use with? | Internal Immersion and External Immersion |
| How can the affects of hard water in domestic hot water heating equipment be minimized? | Lower water temperature and controlling flow |
| What are 6 valves in hot water system? | Check, ball,globe,butterfly,balance |
| What two valves are isolation valves? | Balls valves and gate valves |
| What is a heat exchanger? | |
| Water at ____ can scald in just half a second | 150F |
| ___ valve is used for throttling and shut off purpose | Globe valve |
| Balance valves are used for what? | To balance or equalize circulation |
| What are butterfly valves used for? | Balancing valves and isolate section of piping system |
| Pressure relief valve are set to relief system if pressure exceeds____ | 30 PSIG |