Application Guidelines

For existing furnace applications, the furnace must have a suitable blower size.
Furnace coils built in 2006 or newer can be straight matched to the outdoor unit
tonnage or one size larger*. An R410A TXV is required on the furnace coil.
Furnace coils built between 2005 and 1992 may be straight matched, one or two
tonnage sizes larger than the outdoor unit tonnage*. An R410A TXV must be
added to the indoor coil.
Existing 2-stage indoor equipment
The ICP inverter unit is capable of operating with a standard 2-stage thermostat
and non-communicating 2-stage indoor equipment. In this case, the outdoor unit
will be wired as a 2-stage system, and will operate as a 2-stage system.
Combination ratings will be available with some furnace/coil and FVM4 fan coil
combinations. These ratings will apply to both new and existing equipment of like
model numbers.
For existing furnace applications with the ICP inverter outdoor units, the furnace
must have a suitable blower size and staging capability. Furnace coils built in
2006 or newer may be straight matched to the outdoor unit tonnage or one size
larger*. An R410A TXV is required on the furnace coil. Furnace coils built
between 2005 and 1992 may be straight matched, one or two sizes larger than
the outdoor unit tonnage*. An R410A TXV must be added to the indoor coil.
* Examples
• Straight matched to outdoor unit tonnage – 3-ton AC unit with 3-ton furnace or
fan coil
• One size larger indoor – 3-ton AC unit with 3.5 ton furnace or fan coil
• 2 sizes larger indoor – 3-ton AC unit with older 4 ton furnace coil