AAON M2-036 - Manual (Page 59)

59
Duct Furnace Component Identification
Figure 22 - Horizontal Configuration
Horizontal Airflow Configuration
1. Airflow may be from either right or left
for heater as shown, without any difference
in system performance.
2. Typically no condensate drain attachment
is necessary in “Heat” only applications.
Condensation should not occur during
heating cycle. However, in applications
operating at low temperature rise or with
50% or more outside air, condensation may
occur early in the heating cycle. In these
applications connection of a condensate
drain line is recommended, to avoid
condensate buildup and possible heat
exchanger damage.
3. If heating section is located downstream
of a refrigeration system or cooling coil,
condensation can occur during operation of
the air conditioning, resulting in
condensation from warm, moist air in the
heat exchanger tubes and flue collector. This
condensate is not harmful to the heat
exchanger provided it is drained
continuously. For these applications a 1/4
inch NPT connection is provided for
attachment of condensate drain line to
remove condensate from heat exchanger.
Figure 23 - Vertical Configuration
Vertical Airflow Configuration
1. Airflow may be either upflow or
downflow for heater as shown, without any
difference in system performance.
2. In this configuration, condensate due to
operation of air conditioning system would
drain through the open heat exchanger tubes
near base of heater. An optional condensate
drain pan is available for these applications,
if none is incorporated integral to the unit.
3. Some condensation may occur in the flue
collector box, and it is recommended that a
drain tube be connected to the lower
condensate drain fitting as well.
Gas Valve
Figure 24 - Gas Valve