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hydronic
quick quizzes
88
Other
Undergraduate 3
01/05/2025

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Term
The water flow rates needed in hydronic systems are calculated mathematically based on the ___ difference of the water at two points in a system and the amount of heat transferred during the change of temperature?
Definition
temperature
Term
___ is a function of the weight of HTF and the vertical height of the HTF in a system above the pump.
Definition
static head
Term
Pressure drop ___ as the flow rate increases and the piping size decreases
Definition
increases
Term
The segment pressure drop of piping is found by multiplying the ___ of the segment by the pressure drop.
Definition
equivalent length
Term
In a hydronic system, the water flow velocity should normally be between 2.5 fps and ___ fps
Definition
8
Term
Additives such as inhibitors or glycols are typically mixed with water to protect the system from ___, bacteria, or freezing temperatures.
Definition
corrosion
Term
When HTF temperature rises, the resulting decrease in pressure drop in hydronic systems could be as much as ___%, which could result in oversizing of the piping and circulating pumps.
Definition
30%
Term
In ___ systems, the supply pipe and return pipe are typically the same size in each pipe section between terminal devices.
Definition
two-pipe direct-return
Term
The type of ___ used in a hydronic heating or cooling system depends on the degree of temperature control required in the building.
Definition
terminal unit
Term
One parallel piping installation commonly used in hydronic systems is system ___.
Definition
redundancy
Term
Most technicians today use a(n) ___ to test for voltage, current, and resistance.
Definition
digital multimeter
Term
A water loop system circulates water from a chiller condenser to a cooling tower and back to the chiller condenser, and these water loops are typically ___ systems.
Definition
open
Term
in a water loop system, organic matter may contribute to the growth of ___ contaminants that can clog and foul system components.
Definition
biological
Term
Of the different types of glycol used with hydronic systems, ___ glycol has better heat transfer characteristics, but it is more hazardous to handle during preparation.
Definition
ethylene
Term
___ may be caused by excessive velocity present in a piping system.
Definition
erosion
Term
The ___ system is the largest and potentially most complex part of a hydronic system.
Definition
piping
Term
___ is the process of purging air from a hydronic system while filling it with the appropriate HTF at the proper pressure.
Definition
charging
Term
__ is a formal assessment of the functionality and efficiency of a hydronic system
Definition
commissioning
Term
im copy and pasting all of these so go easy on me if it doesnt quite look right.
Definition
my body is a machine that turns taco bell into pain and regret
Term
The ___-based method of balancing is considered inaccurate and unreliable and is used only in limited cases and as a last resort.
Definition
temperature
Term
___ maintenance is scheduled and unscheduled work required and expected to keep equipment in peak operating condition.
Definition
preventive
Term
A(n) ___ is a device that measures the value of a controlled variable and transmits a signal that conveys this information to a controller.
Definition
sensor
Term
A ___ sensor is a sensor that measures the pressure exerted by a fluid, such as air or water.
Definition
pressure
Term
The most common type of airflow station is a ___ station.
Definition
pitot tube
Term
Hardware-based ___ are basically small computers that are specially designed to gather, process, and display system data.
Definition
human-machine interfaces
Term
A disadvantage of ___ signals is that electrical noise, which is normal to some degree in any electrical system, can affect the signals by changing their intended values slightly.
Definition
analog
Term
A(n) ___ is a narrative that details the operation of a system and its interaction with other systems in a logical order.
Definition
sequence of operation
Term
A(n) ___ is the desired value to be maintained by a system.
Definition
setpoint
Term
___ control is a control strategy that alternates the operation of two or more similar pieces of equipment in the same system.
Definition
lead/lag
Term
A(n) ___ control algorithm is a PID control algorithm that automatically adjusts its parameters based on environmental conditions.
Definition
adaptive
Term
___ control is a supervisory control function in which the load is turned on as late as possible to achieve the indoor environment setpoints by the beginning of building occupancy.
Definition
optimum start
Term
Radiant panels release 50% to 70% of their heat to a room by radiation and provide the balance of the heat by ___.
Definition
convection
Term
The aluminum layer in ___ limits oxygen diffusion through the walls of the tubing
Definition
pex-al-pex
Term
The most commonly used panel tubing arrangement is the ___ coil method.
Definition
sssssserpentine
Term
A ___ valve is provided at each circuit, or for each area where the flow of HTF must be controlled, in order to provide equal distribution of heat transfer to each zone.
Definition
balancing
Term
Floor surface temperatures should not exceed ___°F in building areas where foot traffic is expected, except where specified by the designer or manufacturer because of floor covering thermal insulation.
Definition
85
Term
If the space above a ceiling radiant panel is unconditioned, the minimum R-value is R-___.
Definition
r-30
Term
___-value is the measure of thermal resistance of a material or product.
Definition
R
Term
In the ___ method, subfloor spacers or sleepers separate the tubing and suspend the finished flooring above the tube.
Definition
sandwich
Term
___ is the controlled and forced phase change of snow and/or ice to liquid and vapor with effluent being drained away from a surface in a safe manner.
Definition
snow and ice melting
Term
Thermal insulation for a snow- and ice-melt system should have a minimum R-___ value and be resistant to water absorption.
Definition
R-1
Term
There are ___ types of terminal units commonly used in hydronic heating systems.
Definition
2 (radiant and convection)
Term
A ___ radiator is a radiator designed to function more efficiently and at lower HTF temperatures than a traditional radiator.
Definition
panel radiator
Term
___ systems are used on driveways, walkways, parking areas, stairways, ramps, loading docks, and other outside surfaces.
Definition
snow melt
Term
A ___ convection unit is a convection terminal unit that creates convective currents by mechanically moving air past a terminal unit element.
Definition
forced air
Term
The ___ in a cabinet unit heater adds energy to the air so that directional louvers can be used on the top or front of the heater to distribute the air more efficiently in a building space.
Definition
blower
Term
A ___ heater is a self-contained, forced-air convection heater that is not connected to ductwork and contains a fan, an HTF coil, and controls in one cabinet.
Definition
unit heater
Term
A ___ is intended to supply air only to the room where it is located.
Definition
fan coil unit
Term
The difference between the draw-through and blow-through AHU fan types is in the ___ of air produced by the unit
Definition
temperature
Term
A(n) ___ of conditioned spaces below 30% tends to reduce moisture levels in occupants, which can result in respiratory infections, dry skin, and general discomfort.
Definition
RH (relative humidity)
Term
In most cases, a cooling system will reduce the humidity levels in a space by removing the ___ heat of the moisture in the air.
Definition
latent heat
Term
___ occurs because of a combination of heat transfer by conduction and heat transfer by actual movement of some of a fluid from one place to another.
Definition
natural convection
Term
Heat that causes changes in temperature that can be measured is called ___ heat.
Definition
sensible
Term
A basic unit used to measure a quantity of heat is the __?
Definition
British Thermal Unit
Term
Wet-bulb temperature is the temperature of air if it were cooled to ___% RH
Definition
100%
Term
A(n) ___ thermometer is an instrument designed to measure temperature using a circular scale and pointer.
Definition
dial
Term
Whenever a moving stream of fluid is changed, either in velocity or direction, a ___ is required to cause the change.
Definition
force
Term
A ___ pressure gauge is a mechanical pressure gauge with a curved tube made of thin metal that acts as a pressure-sensing element.
Definition
bourdon tube
Term
___ is the speed water moves through a piping section, typically expressed in feet per second (fps).
Definition
water flow velocity
Term
The ___ line is a large pipe that distributes HTF from the heat source or chiller to smaller branch pipes.
Definition
main
Term
A zone is a section of a building that is controlled by ___ HVAC controlling device(s).
Definition
one
Term
A ___ system is a piping system that circulates HTF through a single main in which each terminal unit serves as a portion of the main.
Definition
series loop
Term
There are ___ main styles of diversion fittings currently in use.
Definition
2. monoflo and venturi
Term
A ___ changeover is the most commonly used changeover method using two three-way valves connected to the terminal unit or zone piping on a four-pipe system.
Definition
conventional 3 way valve
Term
___ are silent, efficient, nonelectric control valves that provide reliable temperature control for hydronic terminal units.
Definition
thermostatic control valves
Term
In a direct-return system, the first terminal unit taken off the supply main is the ___ to connect to the return main.
Definition
last. this also meant the first terminal unit is the closest unit to the heating or cooling source
Term
A ___-pipe system permits any zone or building space to be heated or cooled independently of any other zone, although all zones are supplied by the same piping.
Definition
3 pipe system
Term
In a four-pipe system, a ___ valve is generally recommended when high differential pressures are encountered.
Definition
double seated 2 way
Term
A hydronic system is divided into piping areas described as primary, secondary, and tertiary ___, determined by their relationship to the heat source or chiller and the piping configuration.
Definition
circuits or loops
Term
The objective of any building heating or cooling system, including a hydronic system, is to provide the ___ possible.
Definition
maximum human comfort
Term
The typical modern hydronic heating and cooling system is divided into ___ main parts.
Definition
3. the heating and cooling sources, the distribution system, and the terminal units.
Term
Hydronic system equipment that is normally installed in a mechanical room includes ___.
Definition
a boiler or other heat source to heat the htf
Term
A ___ hydronic system is a hydronic system in which circulation to the heating units is accomplished by the difference in the density of water in the supply and return mains.
Definition
gravity
Term
___ systems may be arranged in either direct return or reverse return system designs.
Definition
2 pipe. 2 pipe system utilize one man for supply htf and one main for return htf.
Term
___ units include baseboard radiation terminal units and radiant panel terminal units.
Definition
radiant
Term
In both winter and summer ___ water can be heated using the same boiler.
Definition
domestic
Term
There are ___ basic hydronic system distribution types.
Definition
4. one pipe, two pipe, three pipe, four pipe.
Term
A(n) ___ burner consists of a forced air fan that is used to bring air under pressure into close contact with fuel.
Definition
power burner
Term
___ boilers are normally water-tube boilers that use a configuration of finned copper tubes with headers as the heat exchanger.
Definition
copper
Term
___ draft is mechanical draft from air pulled through a boiler combustion chamber with fans located in the breeching.
Definition
induced draft
Term
According to manufacturers, the operating efficiency of ___ boilers can be as high as 98%.
Definition
condensing
Term
A(n) ___ is a device that controls the starting, stopping, and firing rate of a hot water boiler burner by measuring the temperature of the water in the boiler.
Definition
aquastat
Term
A ___ utilizes a paddle to sense fluid flow and physically close an electrical circuit, allowing power to the boiler burner.
Definition
flow switch
Term
The hydronic cooling cycle is composed of ___ separate and distinct cycles that create the complete hydronic cooling system.
Definition
5. The space cooling cycle, the evap cycle, the compressor cycle, the condenser cycle, and the cooling tower cycle.
Term
A ___ cooling system uses water's cooling capacity a single time.
Definition
once-through.
Term
The ___ is the reservoir located above a cooling tower to hold heated water prior to its flow through the fill.
Definition
distribution basin
Term
A ___ heat exchanger is an external tube-type heat exchanger that consists of a large pressure vessel with multiple tubes that run through it.
Definition
shell and tube
Term
The single greatest lead singer of all time?
Definition
Chris Cornell of course.
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