Which of the following control is variation of ON / OFF Control.
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Reverse reset means that as the signal from the secondary sensor drops, the setpoint of the controller decreases.
Refrigerated air–conditioning will ____:
The absolute pressure of a gas at constant temperature varies _______ as its volume:
The chiller dehydrator removes which of the following from refrigerant:
According to ASHRAE, the outside fresh air requirement for both residencies and apartments ranges from:
Pneumatic controls cannot operation at part load condition:
The load on the condenser will decrease with increase in the compression ratio:
Which one of the following is not an HVAC control actuator:
When the damper makes up a significant portion of the total system pressure loss, which of the dampers are used:
Cooling of air without any condensation of moisture is purely sensible cooling
A Mixing Valve is used normally for radiator circuits:
_____ measure the velocity of sound waves propagating through a fluid between to points on the length of a pipe.
Which of the following controllers have setpoint and throttling range scales labeled in degrees F or C.
The quantity of air to be distributed to various rooms, wings or zones of the building should be in proportional to the load in the respective areas:
Which one of the following device wide range of operation characteristics:
_____ is the desired condition of a variable that is to be maintained
In a duct system, in which of the following case there will be more pressure drop (loss):
The relative humidity of the air _____ as the temperature increases
RTDs are used in measuring which of the following quantities:
An activated ____ adsorber removes gaseous contaminants from the air
_____ is an instrument used to measure relative humidity
The capacitance value of the circuit of a capacitance sensors ______ with increase in liquid level in the tank
With direct reset, as the signal for the _____ input increases, the setpoint increases.
The dew point temperature is the temperature at which moisture begins to condense out of the air.
Ultrasonic flow sensors is to measure which of the following:
In case of Proportional (P) control, there will not be any error:
Sealed bellows is used in measuring in which of the following:
Which one of the following is not an RTD:
______ operate on the principle that when a fluid flows around an obstruction in the flow stream
A sensor-transducer assembly is called a ______ :
The density of the water vapor is ____
Electronic controllers cannot modulate a pneumatic actuator:
Which of the following system can accommodate complex control and override schemes:
The Pitot – static tube can be used to measure _____ through the decrease:
In the ducts, pressure of the air falls because of which of the following:
A ______ duct with its high strength to weight ratio is suitable for distribution systems:
The larger the condenser area exposed to the moving airstream, the ____ the temperature of the refrigerant when it leaves the condenser
When there is an abrupt expansion in the duct, the pressure loss in the duct will be:
Which of the following cooling methods are generally found in large commercial and industrial applications: