AAON LL-540 - Manual (Page 29)

29
Gas Connection
For LL Series outdoor mechanical units with
boiler systems, size gas piping to supply the
unit with proper pressure when all gas
consuming
devices in the building
connected to the same gas system are
operating. The maximum gas train inlet
pressure for all boiler sizes is 5 psig. The
minimum gas train inlet pressure for the 500
MBH boiler is 5 inches of water column,
and for all other boilers, 7 inches of water
column.
Carefully consider all current and future gas
usage. Table 3 details the input rate for each
boiler unit.
Gas connection sizes are listed on the unit
rating sheet.
Table 3 - Boiler Rated Input Capacity
Boiler Size
Rated Capacity (CFH)*
Natural LP/Propane
500 MBH 500 200
750 MBH 750 300
1000 MBH 1000 400
1500 MBH 1500 600
*Note: Rating is for sea level conditions.
For additional information regarding the gas
piping
connection, see the Thermal
Solutions Boiler “Installation, Operating,
and Service Instructions” that are included
with the unit.
Boiler Exhaust Connection
In addition to gas connection installation,
each boiler requires installation of the
exhaust vent piping and inlet vent hood. The
exhaust panel with chimney cutout is
removed for shipping, and replaced with a
shipping cover.
Figure 7 - Boiler Vent Shipping Covers
Remove the shipping cover and attach the
exhaust panel shipped with the unit. When
the exhaust panel is securely fastened with
Boilers must be operated only with
liquid flowing through the boiler.
WARNING
Installing Contractor is responsible
for proper sealing of the water piping
entries into the unit Failure to seal the
entries may result in damage to the
unit and property.
CAUTION