13
Step 5 —
Check Duct System
A supply air outlet collar and return air duct flange are provided
on all units to facilitate duct connections. Fold the duct flange out
-
wards along the perforated line. Refer to Fig. 2-6 for physical di
-
mensions of the collar and flange
NOTE: All dual fan units (50HQP 120 and 180-242, 50VQP 210-
360) must use a “pair of pants” duct configuration as shown in
Fig. 10. Failure to follow these guidelines can result in fan system
failure.
Fig. 10 —
Typical Fan Discharge Connections for
Multiple Fan Units
Refer to the Carrier System Design Manual or ASHRAE
(American Society of Heating, Refrigerating and Air-Condition
-
ing Engineers) standards for the recommended duct connection to
unit with 2 fans. An adequate straight length of ducting from the
unit should be allowed before elbows are installed. Elbows should
turn in the direction of fan rotation, if possible. Abrupt turns will
generate air turbulence and excessive noise. Turning vanes should
be used in all short radius bends. Ensure that ducting does not ob
-
struct access to the unit for routine servicing.
A flexible connector is recommended for supply and return air
connections on metal duct systems. All metal ducting should be
insulated with a minimum of one inch duct insulation to avoid
heat loss or gain and prevent condensate forming during the cool
-
ing operation. Application of the unit to uninsulated duct work is
not recommended as the unit's performance will be adversely af
-
fected. Do not connect discharge ducts directly to the blower out
-
let. The factory provided air filter must be removed when using a
filter back return air grille.The factory filter should be left in place
on a free return system. If the unit will be installed in a new
installation with new ductwork, the installation should be designed
using current ASHRAE (American Society of Heating, Refriger
-
ating, and Air-Conditioning Engineers) procedures for duct sizing.
If the unit will be connected to an existing duct system, a check
should be made to assure that the duct system has the capacity to
handle the air required for the unit application. If the duct system
is too small, larger ductwork must be installed. Be certain to check
for existing leaks and repair.
The duct system and all diffusers should be sized to handle the de
-
signed airflow quietly. To maximize sound attenuation of the unit
blower, the supply and return air plenums should be insulated.
There should be no direct straight air path through the return-air
grille into the heat pump. The return air inlet to the heat pump
must have at least one 90 degree turn away from the space return
air grille. If air noise or excessive airflow are a problem, the blow
-
er speed can be changed to a lower speed to reduce airflow.
Step 6 —
Install Condensate Drain
A drain line must be connected to the heat pump and pitched away
from the unit a minimum of
1
/
8
-in. per foot to allow the condensate
to flow away from the unit. 50VQP Vertical units include one con
-
densate drain. 50HQP horizontal units include two condensate
drain connections to allow for field pitching based on installation
requirements. Only one condensate drain connection should be
used. Cap and seal the unused drain connection.
Units with waterside economizer include an additional condensate
pan and drain as part of the economizer assembly. This drain must
also be piped to a condensate line following the guidance above.
NOTE: the waterside economizer condensate pan is not protected
by a condensate overflow switch from the factory.
This connection must be in conformance with local plumbing
codes. A trap must be installed in the condensate line to ensure
free condensate flow. (Units are not internally trapped.) A vertical
air vent is sometimes required to avoid air pockets. (See Fig. 11.)
The length of the trap depends on the amount of positive or nega
-
tive pressure on the drain pan.
Fig. 11 —
Condensate Trapping
A second trap must not be included. The horizontal unit should be
pitched approximately
1
/
4
-in. towards the drain in both directions,
to facilitate condensate removal. (See Fig. 12.)
A
B
a50-8357.eps
NOTE: A = 1
1
/
2
to 2
1
/
2
B
CAUTION
Verify condensate switch is installed in the lowest part of the
drain pan, based on unit pitch. Condensate switch may need to
be relocated from factory position.
Summary of Contents for Aquazone 50HQP 072
Page 23: ...23 Fig 20 Single Phase with WSHP Open ...
Page 26: ...26 Fig 23 3 Phase with WSHP Open ...
Page 28: ...28 Fig 25 3 Phase Deluxe D Control Package with 1 Speed VFD and Hot Gas Reheat ...
Page 29: ...29 Fig 26 3 Phase with WSHP Open Hot Gas Reheat Water Economizer and SAVTM ...
Page 31: ...31 Fig 28 WSHP Open W2A Wiring Diagram ...
