Heat Controller HTV Series Installation, Operation & Maintenance Instructions Manual page 12

Condensate Piping – Horizontal Units
Pitch the unit toward the drain as shown in Figure 2 to
improve the condensate drainage. On small units (less
than 2.5 tons/8.8 kW), insure that unit pitch does not cause
condensate leaks inside the cabinet.
Install condensate trap at each unit with the top of the trap
positioned below the unit condensate drain connection as
shown in Figure 6. Design the depth of the trap (water-
seal) based upon the amount of ESP capability of the
blower (where 2 inches [51mm] of ESP capability requires
2 inches [51mm] of trap depth). As a general rule, 1-1/2
inch [38mm] trap depth is the minimum.
Each unit must be installed with its own individual trap and
connection to the condensate line (main) or riser. Provide
a means to flush or blow out the condensate line. DO NOT
install units with a common trap and/or vent.
Always vent the condensate line when dirt or air can collect
in the line or a long horizontal drain line is required. Also
vent when large units are working against higher external
static pressure than other units connected to the same
condensate main since this may cause poor drainage for all
units on the line. WHEN A VENT IS INSTALLED IN THE
DRAIN LINE, IT MUST BE LOCATED AFTER THE TRAP
IN THE DIRECTION OF THE CONDENSATE FLOW.
Duct System Installation
The duct system should be sized to handle the design
airflow quietly. Refer to Figure 3 for horizontal duct system
details or figure 8 for vertical duct system details. A flexible
connector is recommended for both discharge and return
air duct connections on metal duct systems to eliminate
the transfer of vibration to the duct system. To maximize
sound attenuation of the unit blower, the supply and return
plenums should include internal fiberglass duct liner or be
constructed from ductboard for the first few feet. Application
of the unit to uninsulated ductwork in an unconditioned
space is not recommended, as the unit's performance will
be adversely affected.
HTV/HTD/HTH SERIES
DUCT SYSTEM INSTALLATION
11
Figure 6: Horizontal Condensate Connection
*3/4" IPT
Trap Depth
1.5" [38mm]
3/4" PVC or
Copper by others
* Some units include a painted drain
connection. Using a threaded pipe or
similar device to clear any excess paint
accumulated inside this fitting may
ease final drain line installation.
CAUTION!
CAUTION! Ensure condensate line is pitched toward
drain 1/4" per foot [21mm per m] of run.
At least one 90° elbow should be included in the supply
duct to reduce air noise. If air noise or excessive air flow is
a problem, the blower speed can be changed. For airflow
charts, consult specifications catalog for the series and
model of the specific unit.
If the unit is connected to existing ductwork, a previous
check should have been made to insure that the ductwork
has the capacity to handle the airflow required for the unit.
If ducting is too small, as in the replacement of a heating
only system, larger ductwork should be installed. All
existing ductwork should be checked for leaks and repaired
as necessary.
Heat Controller, Inc.
Vent
Min 1.5"
[38mm]
1/4" per foot
(21mm per m)
drain slope
Rev.: 6/26/09S