Amana AMVM97 Service Instructions Manual page 17

PRODUCT DESIGN
• If the furnace is installed horizontally, ensure the access
doors are not on the "up/top" or "down/bottom" side
of the furnace.
• Do not connect this furnace to a chimney flue that serves
a separate appliance designed to burn solid fuel.
• On Counterflow Installations, the air conditioning coil
must be downstream on the supply (positive) side of the
furnace heat exchanger.
• Counterflow Installation over a noncombustible floor.
Before setting the furnace over the plenum opening, en-
sure the surface around the opening is smooth and level.
A tight seal should be made between the furnace base
and floor by using a silicone rubber caulking compound
or cement grout.
• Counterflow Installation over a combustible floor. If in-
stallation over a combustible floor becomes necessary,
use an accessory subbase (see Specification Sheet ap-
plicable for your model for details.) A special accessory
subbase must be used for upright counterflow unit in-
stallations over any combustible material including wood.
Refer to subbase instructions for installation details.
Follow the instructions with the subbase for proper in-
stallation.
Do not install the furnace directly on carpeting, tile, or
other combustible material other than wood flooring.
(NOTE: The subbase will not be required if an air condi-
tioning coil is installed between the supply air opening
on the furnace and the floor.)
Furnace Components
Heat Exchanger Assembly
The primary heat exchanger is a tubular type constructed
of high quality steel (409 stainless steel for Amana Brand,
aluminized for Goodman) the heat exchanger assembly con-
sists of primary and secondary sections crimped together
on a back transition plate. The secondary heat exchanger
is a single pass coil consisting of AL29-4C stainless steel
tubes and aluminum fins. These stainless steel tubes are
expanded on to the aluminum fins to enhance heat trans-
fer. Each tube in the secondary heat exchanger contains
an internal turbulator to effectively scrub heat from the
flue gases. The primary and secondary heat exchanger sec-
tions are joined by a 441 stainless steel header plate. Flue
gas condensation takes place in the secondary heat ex-
changer as latent heat is transferred from the flue gases to
heat the conditioned space.
Burners
Burners have been redesigned for 34.5" chassis furnaces.
Overall length and width dimensions remain the same as
40" model burners. The burners used 34.5" models have
burner head insert with larger diameter center hole and a
larger number of surrounding holes.
New 34.5 Burner
Depending on the size of the furnace, each furnace will have
from three to six inshot burners. Burners are precisely con-
structed of aluminized steel and designed to provide proper
ignition and flame stability.
Gas Manifold Assembly
Each gas manifold is fitted with the appropriate number of
#45 natural gas orifices. At 100% of gas input, each burner
will provide approximately 20,000 BTUH. The A/
GMVM951155DX models uses #43 gas orifices at 22,500 per
hour. If converting to LP gas, the factory installed mani-
fold assembly must be replaced by the manifold assembly
provided in the LP kit.
ECM Motor
A variable speed ECM four wire indoor fan motor provides
supply air to the conditioned space. This is the same motor
used on Goodman & Amana previous generation communi-
cating furnaces.
Induced Draft Blower (IDB)
All modulating furnace models use a three phase induced
draft blower to draw flue gases through the heat exchanger.
The inducer uses ball bearings and is permanently lubri-
cated. This motor is driven at varying speeds by the VFD
(variable frequency drive) section of the IFC. The IFC takes
typical single phase power supplied to the furnace and con-
verts it to a three phase supply to operate the draft inducer
at the desired speed. The windings of the induced draft
motor will have equal resistance +/- 5%. Normal resistance
readings at room temperature will range from 14-17 ohms.
The voltage supplied by the IFC to drive the induced draft
blower will vary from 15-110 volts A/C between any two
windings. This would be read between any two of the three
power wires between the IFC and the induced draft blower.
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