Solutions
When changing out an evaporator coil the installer must be certain to plumb the cabinet so its
sides are vertical
The recommended maximum external static pressure used for heating and cooling equipment
with blowers for 5 ton of cooling or less is 0.1 in W.C
When a balancing check of a newly installed duct system the dampers should be open
completely in all rooms
Operating sound is a consideration in the location of a condensing unit because excessive
noise could be disruptive to the customer
A technician has determined a supply in a flexible duct system is leaking so All connections
including inner and outer layers should be checked
Sensible heat ratio is sensible removed ÷ total heat removed
,A wet bulb reading that is very close to the dry bulb reading from the same instrument indicates
the relative humidity is very high
The following measurements would be needed to properly evaluate a complaint of "drafty"
operation with a heating system are: system TD, drop, and static pressure
The kind of energy that the condenser removes from the refrigerant is sensible and latent heat
In a simple refrigerant system, the refrigerant boils in the evaporator
The common suction line on a heat pump is connected between the indoor coil and the
compressor
There are two generally used methods for changing capacity on demand in a heat pump. One is
to use a _______ and the other method is two speed compressor, using a two stage thermostat
, The three things that happen when a heat pump is cycled into the defrost mode are: the
reversing valve switches to the cooling mode, the outdoor fan is shut off and the auxiliary heat is
energized
An extended plenum duct system is a single trunk extending in one or two directions with
many branch ducts
The effect on supply airflow when static pressure on the return is reduced is airflow will be
increased
The voltage most often used to power the outdoor unit in a residential system is 240V single
phase
Residential control or low voltage wiring normally is shielded wired
If you increased suction pressure on a reciprocating compressor the capacity would decrease
The refrigerants typically used in residential and light commercial pumps have a storage life of
an indefinite length of time