Goodman AMH8 Service Instructions Manual page 45

MAINTENANCE
gas and with proper inlet pressures and correct piping size,
full capacity will be obtained.
With propane gas, no unit gas valve regulator is used; how-
ever, the second stage supply line pressure regulator should
be adjusted to give 11" water column with all other gas
consuming appliances running.
The dissipation of the heat transferred to the heat exchanger
is now controlled by the amount of air circulated over its
surface.
The amount (CFM) of air circulated is governed by the
external static pressure in inches of water column of duct
work, cooling coil, registers, etc., applied externally to the
unit versus the motor speed tap (direct drive).
A properly operating unit must have the BTU per hour input
and CFM of air, within the limits shown to prevent short
cycling of the equipment. As the external static pressure
goes up, the temperature rise will also increase. Consult
the proper tables for temperature rise limitation.
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