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52 Cards in this Set
- Front
- Back
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The reason for using zone valves on a hydronic heating system is to _____.
A. allow different areas of the structure to maintain different temperatures B. reduce the chance of a water leak C. prevent unused parts of the house from getting warm, and wasting energy D. both A and C |
D. both A and C
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Air in a hydronic system can cause ____.
A. reduced water circulation B. increased efficiency C. corrosion D. both A and B |
D. both A and B
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A pressure relief valve is set for 30 psig. The valve is constantly opening and flooding the floor. What should the technician do?
A. Increase the set point of the relief valve to 40 psig. B. Find the cause of overfiring. C. Put a bucket under the valve. D. Both A. and C are correct. |
B. Find the cause of overfiring.
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A series loop hydronic system is not desirable for use in a large residence because ____.
A. all of the heated water will flow to all rooms B. some rooms will overheat before other rooms warm C. they are extremely noisy D. both A and B |
A. all of the heated water will flow to all rooms
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A limit control on a hot water boiler is needed to ____.
A. regulate the amount of water to each section of baseboard B. regulate the water in the supply line to the boiler C. balance the water flow rate in the piping system D. protect the boiler against excessive water temperatures |
D. protect the boiler against excessive water temperatures
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The pressure relief valve ____ .
A. regulates the pressure of the water in the supply line B. is set to relieve the pressure in the boiler below the maximum design pressure of the boiler C. shuts the boiler off if the water temperature gets too high D. relieves the pressure in the expansion tank |
B. is set to relieve the pressure in the boiler below the maximum design pressure of the boiler
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The expansion tank provides a means of removing the air from the system as well as ____ .
A. provides a space for excess water from the supply source B. provides water for the domestic hot water coil C. provides a space for water expansion and contraction with water temperature changes D. all of the above |
C. provides a space for water expansion and contraction with water temperature changes
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An expansion joint is a devise used to ____ .
A. prevent damage between boiler sections B. connect the expansion tank into the system C. allow for expansion and contraction of the loop piping with water temperature changes D. connect the manual vent into the system |
C. allow for expansion and contraction of the loop piping with water temperature changes
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In a series loop hydronic heating piping system ____ .
A. the heated water flows in the same direction in parallel pipes B. the heated water flows in the opposite direction in parallel pipes C. part of the heated water is directed to each terminal unit D. all the heated water flows through all the terminal units |
D. all the heated water flows through all the terminal units
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A column of water one foot high exerts a pressure of ____ .
A. 0.369 psig B. 0.407 psig C. 0.433 psig D. 0.496 psig |
C. 0.433 psig
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Air in the hot water circulating system will cause ____ .
A . corrosion B. noise C. flow blockage D. all of the above |
D. all of the above
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If air conditioning is to be added to an existinig forced-air heating system, what must be taken in to acount?
A. duct size B. fan speed C. required air volume D. all of the above |
D. all of the above
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A three ton air conditioning unit will require approximately ____ of air flow.
A. 400 CFM/ton B. 1,200 CFM C. 1,200 CFM/ton D. both A and B |
D. both A and B
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What can be done to prevent ductwork from sweating?
A. Lower the thermostat setting. B. Add dampers. C. Insulate the duct. D. Both A and C are correct. |
C. Insulate the duct.
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Typically, an air-conditioning (cooling) system requires an airflow through the evaporator of ____ cfm per 12,000 Btu/h capacity.
A. 340 B. 360 C. 400 D. 420 |
C. 400 cfm
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In evaluating an air distribution system, the terminal units called the ____ are an important factor.
A. electric baseboard and radiators B. evaporators and condenser C. registers and grills D. blower and damper |
C. registers and grills
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When adding a summer cooling system to an existing heating system, frequently a ____ must be added to the control circuit.
A. thermocouple and limit switch B. glow coil and static pressure disc C. transformer and fan relay D. stack switch and CAD cell |
C. transformer and fan relay
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When designing an all weather system, the air distribution system is designed around ____ .
A. the cooling requirement B. the heating requirement C. either heating or cooling requirements D. both heating and cooling requirements |
D. both heating and cooling requirements
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Package or self-contained all-weather units are not normally made for electric air conditioning and ____ .
A. natural gas heat B. electric heat C. LP gas heat D. oil heat |
D. oil heat
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The heat anticipator in a thermostat is often a(n) ____ type resistor.
A. ceramic block B. carbon block C. adjustable thermistor D. adjustable wire wound |
D. adjustable wire wound
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The cooling anticipator in a thermostat is a(n) ____ type resistor.
A. combination B. fixed C. adjustable thermistor D. adjustable wire wound |
B. fixed
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When adding a control transformer for an air-conditioning system to an existing heating system, the second transformer can be wired in parellel with the original or ____ .
A. in series with the original transformer B. as a seperate circuit C. in parallel with the fan relay D. in parallel with the compressor contactor |
B. as a seperate circuit
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True or False, When an oil or gas boiler is used, the water chamber is divided into smaller compartments to increase the surface area on which the heat can act.
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True
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True or False, If a parallel hydronic system is installed, it maybe necessary to bleed air from each of the parallel circuits.
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True
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True or False, Expansion tanks must always be bled from the top until all of the air is removed.
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False
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True or False, It is possible for a hydronic system with many zones to operate with one circulating pump.
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True
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True or False, Hydronic heat circulators are centrifugal pumps.
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True
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True or False, In a series loop, the water going through the last terminal unit will be the same temperature as the water through the first terminal unit.
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False
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True or False, The only place a bleed valve is needed is on top of the boiler.
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False
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True or False, A tankless domestic water system provides hot water from a coil in the boiler.
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True
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True or False, One problem with using too large a blower on a heating system is that the products of combustion may condense.
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True
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True or False, If a 1,200 cfm of air is pushed through a duct that is designed for 800 cfm, the result will be increase in duct noise.
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True
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True or False, The required air flow for air conditioning is the same as for heating.
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False
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True or False, If a system utilizes two transformers, an isolating subbase should be used.
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True
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True or False, In the average year-round system installation, the cooling mode will require more cfm than the heating mode.
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True
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True or False, A 36,000 Btu/h air-conditioning system can be added to a 60,000 Btu/h heating system with no need for changes in the heating unit.
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False
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True or False, Not changing air filters can often cost more than the price of the filter.
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True
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Hydronic heating can refer to both ______ and ______ .
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water and steam
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the devise that will shut down a boiler if the water temperature gets too high is called a ______ .
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limit control
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The most popular way of heating using a hot water system is by the use of ________ on the outer walls of the area.
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fin type baseboard
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The zone control valves are controlled by ________ .
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Thermostats
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the main source of air into a hydronic system is the ________ .
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makeup water
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Hot water boiler limit controls are usually set at _____ °F
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210 °F
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Circulators in hydronic systems use impellers with vanes between side plates. These are called ______ impellers.
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Closed impellers
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The material used to make circulator impellers is ______ .
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bronze
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An automatic air bleed valve controls the airflow out of the system by means of a ________ .
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float valve
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Air is conditioned when it is ______, ______, ______, ______, or ______ .
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heated , cooled, dehumidified, humidfied or cleaned
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On a system equipped with gas heat and electric air conditioning, automatic blower operation is controlled by the ________ for the cooling and by the __________ for the heating.
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thermostat for cooling and the fan delay relay for heating
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It is common to see ________ fan on systems that provide heating as well as cooling.
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Multi-speed
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When two transformers are wired in parallel, care must be taken to ensure that they are wired ________ .
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in phase
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A heating anticipator is wired in ________ with the heating contacts.
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series
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A cooling anticipator is wired in ________ with the cooling contacts.
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parallel
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