hva Flashcards
Coolant that is evaporating or boiling is _____
cold
Coolant that is condensing is _____
warm
Low pressure induces _____ and high pressure induces _____
boiling,
condensation
releasing the pressure in an aerosol can causes _____
rapid cooling, it is boiling to release the pressure
An economizer cycle ______
introduces night time outside air to assist cooling
heat pump heating is ______ and best used in milder climates
inefficient, the compressor needs a lot of energy to work
Typically we want a building slightly _____ pressurized
positively, so as to not suck outside air in through infiltration or even worse it could suck outside moisture in
Name the main disadvantage of a VAV system
It cannot heat and cool separate zones at the same time, so it is critical that zones are established correctly
Oversized HVAC systems are problematic because
More costly, Less efficient, and most importantly with a larger unit the cooling coils cannot pick up enough moisture to dehumidify the space while cooling
Which likely has a longer duct run to the space it serves and FCU or AHU
Fan Coil Unit as it is usually in the actual space. It is also louder because a fan is in the actual space. More maintenance as well. But it is much more compact.
In a compression air conditioning loop which is likely to be warmer
Condenser coil (not the evaporator coil)
Mechanical air conditioning can remove both sensible and latent heat, True or False
True, expend more energy when the air condenses on the cooling coil, removing the moisture.
Downstream of the compressor, coolant is under high or low pressure
high
Air should move _____ through ducts
slower, high pressure is inefficient and noisy. also the LARGER the duct the better, more volume means slower air
NC level is the _____ ______ ____
background noise level
