Condensate Disposal Systems - GE 5500 Data Manual

Condensate Disposal Systems

Cooling Condensate
Air conditioners produce condensate water as a result of
lowering the humidity of the area being conditioned. When
the indoor coil temperature is below the dew point,
moisture in the air condenses into water droplets on the
coil. This water drains to a pan located under the indoor
coil and is routed through the barrier, the partition
separating the indoor and outdoor sides of the unit, to the
base pan on the outdoor side. It is then picked up and
dispersed against the outdoor coil, which is hot when the
unit is in the air conditioning mode. The water is evaporated
into the atmosphere by contact with the hot outdoor coil.
This evaporation process also helps lower the temperature of
the outdoor coil and improves the operating efficiency of
the unit.
Slinger Ring Systems
Packaged Terminal units employ various means of dispersing
the condensate water against the outdoor coil. One of the
most popular, and most effective, means is by the use of a
"slinger ring". A "slinger ring" is a ring around the
circumference of the outdoor fan. The design of the unit
positions the slinger ring very close to the bottom of the
base pan so water in the base pan is lifted by the rotating
ring. Water picked up by the slinger ring will be dispersed
into the air stream and deposited on the hot outdoor coil
where it evaporates.
All Zoneline Series Packaged Terminal Air Conditioners and
Packaged Terminal Heat Pumps utilize a slinger ring for
cooling condensate disposal.
Certification Test Requirements
ARI (Air Conditioning & Refrigerating Institute) requires
that all certified Packaged Terminal Air Conditioners and
Packaged Terminal Heat Pumps pass a cooling condensate
disposal test. One stipulation of the ARI test is that "the test
start with condensate collection pan brimful". In order to
pass the ARI Condensate Disposal Test the unit must operate
continuously for four hours without condensed water
blowing, dripping, or running off the unit casing during the
test or after the unit has been turned off. Under extremely
high outdoor humidity conditions or extreme operating
conditions, such as exceptionally high air infiltration (a door
or window left open while the unit is running, for instance)
it is possible for any air conditioner to be unable to dissipate
all the cooling condensate generated.
All Zoneline Series Packaged Terminal Air Conditioners and
Packaged Terminal Heat Pumps meet the condensate disposal
requirements of ARI standards 310-93 and 380-93.
Heat Pump Condensate
During the operation of a unit in the heat pump, or "reverse
cycle", mode the outdoor coil becomes the cold coil and the
indoor coil becomes the hot coil due to reversing the flow of
the refrigerant. When the temperature of the outdoor coil is
below the dew point, condensation will form on the outdoor
coil just as it does on the indoor coil during cooling
operation. Since the dew point is humidity as well as
temperature related, there may be more condensate on days
when the relative humidity is high.
Heat Pump Condensate Disposal
Since the outdoor coil is cold during heat pump operation,
the condensate water cannot be deposited on the outdoor
coil as the water would cause frost to form on the coil. This
frost would block the air flow through the coil and greatly
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diminish the ability of the heat pump to extract heat from
the outdoor air. Rather than allow this problem to occur,
heat pump units must dispose of the condensate in another
manner.
Temperature Activated Drain Valve
The most widely used method
of disposing of heat pump
condensate is with a
"Temperature Activated Drain
Valve". This is a device
mounted in the base pan of a
heat pump unit with a bellows
that expands on temperature
rise and contracts with
temperature drop. A shaft with
a rubber plug on the end is
connected to the bellows.
When the outdoor
temperature remains above a
certain temperature, the
bellows is expanded and the
plug fits tightly into a hole in
the bottom, or base pan, of the unit. When the plug is
blocking the hole, as it should be during cooling operation,
the condensate water is contained in the base pan. At
temperatures when heating is required, the bellows
contracts, the rubber plug is retracted from the hole and the
heat pump condensate water is allowed to drain into the wall
case. The valve is fully open at 49°F.
Drain Kits
Although the Zoneline units are designed to dissipate all of
the condensate generated during normal cooling operation,
there may be times when abnormal operating conditions
cause more condensate than the unit can dissipate. Heat
pumps also generate condensate that the unit may not be
designed to dissipate. For these reasons, if condensate
dripping from the wall case is objectionable, an internal or
external drain system should be installed. See pages 35 and
36 for information covering the drain systems and the
RAD10 kit available to connect to the wall case.
Internal Condensate Removal (ICR) System
GE has developed an Internal Condensate Removal (ICR)
System for Packaged Terminal Heat Pumps. This system has
been offered as an option on Zoneline Packaged Terminal
Heat Pumps since 1982, and thousands of them are in use.
During heat pump operation the ICR system utilizes a small
pump to lift the water from the base pan and pump it into a
collector tray positioned above the indoor coil. The water
drains from the collector tray and drips onto the warm
indoor coil where it is evaporated into the room atmosphere.
If an excess amount of water is pumped to the indoor side, it
is routed back to the outdoor portion of the base pan.
The ICR system has proven to be an effective means of
minimizing the amount of heat pump condensate dripping
from the unit. However, if the restrictions of a particular
installation will allow absolutely no drippage of condensate
water from the wall case, the installation of an internal or
external drain system is recommended.
Units with ICR may not be installed in seacoast or corrosive
environment applications.