Amana GUX-X User manual

August 1996 (1)
As a professional installer you have an obligation to
know the product better than the customer. This
includes all safety precautions and related items.
Prior to actual installation, thoroughly familiarize your-
self with this Instruction Manual. Pay special atten-
tion to all safety warnings. Often during installation or
repair it is possible to place yourself in a position
which is more hazardous than when the unit is in
operation.
Remember, it is your responsibility to install the
product safely and to know it well enough to be able
to instruct a customer in its safe use.
Safety is a matter of common sense...a matter of
thinking before acting. Most dealers have a list of
specific good safety practices...follow them.
The precautions listed in this Installation Manual
should not supersede existing practices but should
be considered as supplemental information.
Amana Refrigeration, Inc.
Fayetteville, TN 37334
ATTENTION INSTALLING PERSONNEL
Amana Forced Air Central Furnace Design Complies With Requirements
Embodied in The American National Standard / National Standard of Canada
Shown Below.
ANSI Z21.47CAN/CGA-2.3 Central Furnaces
GUX-X, GUC-X, and GUD-X
Gas Fired Warm Air
Furnace
RECOGNIZE THIS SYMBOL AS A SAFETY PRECAUTION
Installation Instructions
Affix this manual, Specification Sheet and Users
Information Manual adjacent to the furnace.
Contents
To The Owner................................................................................. 2
To The Installer ............................................................................... 2
I. Safety and Unit Location ............................................................ 3
II. General Information ................................................................... 4
III. Air Requirements ....................................................................... 6
IV. Vent Pipe (All Models) and Combustion Air Pipe
(GUD Models) Materials .......................................................... 8
V. Vent Piping - GUX (All Installations),
GUC (All Installations), and GUD (One Pipe Installations) .... 9
VI. Combustion Air And Vent Piping (GUD - Two Pipe) ............. 11
VII. Condensate Piping ..................................................................15
VIII. Gas Piping ..............................................................................16
lX. Electrical Wiring .......................................................................20
X. Circulating Air and Filters........................................................23
XI. Sequence of Operation ............................................................24
XII. Start-Up and Adjustment ........................................................25
XIII. Maintenance ...........................................................................29
XlV. Functional Parts List ..............................................................32
10318715

2
WARNING
Should overheating occur or the gas
supply fail to shut off, turn off the man-
ual gas control valve to the furnace be-
fore shutting off the electrical supply.
To The Owner
It is important that you fill out the owners registration
card and mail it today. This will assist Amana in con-
tacting you should any service or warranty information
change in the future. When filling in the registration
card, be sure to include the Model, Manufacturing and
Serial Numbers, plus the installation date.
Your warranty certificate is also supplied with the unit.
Read the warranty carefully and note what is covered.
Keep the warranty certificate in a safe place, so you
can find it, if necessary.
If additional operating instructions are required, call
the dealer where the purchase was made.
To The Installer
Before installing this unit, please read this manual to
familiarize yourself on the specific items which must
be adhered to, such as maximum external static pres-
sure to unit, BTU input rating, air temperature rise,
minimum or maximum CFM, and motor speed connec-
tions.
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WARNING
If the information in these instructions
is not followed exactly, a fire or explo-
sion may result causing property dam-
age, personal injury or loss of life.
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
What to do if you smell gas:
 Do not try to light any appliance.
 Do not touch any electrical switch;
do not use any phone in your build-
ing.
 Immediately call your gas supplier
from a neighbors phone. Follow the
gas suppliers instructions.
 If you cannot reach your gas sup-
plier, call the fire department.
Installation and service must be per-
formed by a qualified installer, ser-
vice agency or the gas supplier.

3
Safety
 When the furnace is heating, the temperature of
the return air entering the furnace must be be-
tween 55°F and 100°F.
 If the furnace is installed near an area which will be
frequently contaminated by permanent wave solu-
tions, chlorinated waxes or cleaners, chlorine based
swimming pool chemicals, water softening chemi-
cals, de-icing salts or chemicals, carbon tetrachlo-
ride, halogen type refrigerants, cleaning solutions
(such as perchloroethylene), printing inks, paint
removers, varnishes, hydrochloric acid, cements
and glues, antistatic fabric softeners for clothes
dryers, and masonry acid washing materials, the
furnace should be sealed from this area so that no
contaminated air can reach the furnace. The fur-
nace must still have an adequate supply of com-
bustion air, either from a nearby uncontaminated
room or from outdoors. For details, see AIR RE-
QUIREMENTS Section III.
 Provisions must be made for intake of combustion
air (GUD) and venting combustion products out-
doors through proper venting systems. The length
of combustion air pipe (GUD) and flue pipe could
be a limiting factor in locating the furnace. See
Sections III and IV.
 Allow clearances from the enclosure as shown on
Specification sheet for fire protection, proper op-
eration, and service access. These clearances must
be permanently maintained. The combustion and
ventilating air openings in the front and top panels
of the furnace must never be obstructed.
 When the furnace is used in connection with a
cooling unit, the furnace must be upstream of, or in
parallel with, the cooling unit. For details see Sec-
tion VlI.
 This furnace produces condensate as it operates.
Do not locate the furnace or its condensate drain-
age system in an area subjected to below freezing
temperatures.
I. Safety and Unit Location
WARNING
To prevent personal injury or death due
to improper installation, adjustment, al-
teration, service or maintenance, refer
to this manual or for additional assis-
tance or information consult a qualified
installer, service agency or the gas sup-
plier.
WARNING
This product contains or produces a
chemical or chemicals which may cause
serious illness or death and which are
known to the State of California to cause
cancer, birth defects or other reproduc-
tive harm.
WARNING
To prevent possible death, personal in-
jury or equipment damage due to fire,
the following points must be observed
when installing the unit.
WARNING
To prevent possible death, personal in-
jury or property damage due to electri-
cal shock, the furnace must be located
to protect the electrical components
from water.
CAUTION
This unit must not be used as a
construction heater during the finish-
ing phases of construction on a new
structure. This type of use may result in
premature failure of the unit due to ex-
tremely low return air temperatures and
exposure to corrosive or very dirty at-
mospheres.

4
Location
 The furnace should be as centralized as is practical
with respect to the air distribution system.
 The furnace must be set on a level floor to enable
the condensate produced to drain properly. If the
floor may become wet or damp at times, the fur-
nace should be supported above the floor on a
concrete base sized approximately 1-1/2 larger
than the base of the furnace.
 Do not install the furnace directly on carpeting, tile,
or combustible material other than wood flooring.
 Do not install the furnace where the combustion air
is exposed to the following substances: permanent
wave solutions, chlorinated waxes or cleaners, chlo-
rine based swimming pool chemicals, water soften-
ing chemicals, de-icing salts or chemicals, carbon
tetrachloride, halogen type refrigerants, cleaning
solutions (such as perchloroethylene), printing inks,
paint removers, varnishes, hydrochloric acid, ce-
ments and glues, antistatic fabric softeners for
clothes dryers, and masonry acid washing materi-
als.
 Exposure to contaminated combustion air will result
in safety and performance related problems.
 When installed in a residential garage, the furnace
must be positioned so the burners and ignition source
are located not less than 18 inches (457 mm) above
the floor and protected from physical damage by
vehicles.
II. General Information
WARNING
Possible death, personal injury or prop-
erty damage due to fire, explosion,
smoke, soot, condensation, electrical
shock or carbon monoxide may result
from improper installation, repair, opera-
tion, or maintenance on this product.
WARNING
To prevent death, personal injury or prop-
erty damage due to fire, do not install
this furnace in a mobile home, trailer, or
recreational vehicle.
To ensure this upflow furnace operates safely and effi-
ciently, it must be installed, operated and maintained in
accordance with these installation and operating in-
structions, all local building codes and ordinances, or, in
their absence, with the latest edition of the National
Fuel Gas Code, ANSI Z223.1*, and/or CAN/CGA B149
Installation Codes, local plumbing or waste water codes
and other applicable local codes.
The rated heating capacity of the furnace should be
greater than or equal to the total heat loss of the area to
be heated. The total heat loss should be calculated by
an approved method or in accordance with A.S.H.R.A.E.
Guide or Manual J-Load Calculations published by
the Air Conditioning Contractors of America.
*Obtain from: American National Standards Institute
1430 Broadway New York. NY 10018
Transportation Damage
All furnaces are securely packed in shipping containers
tested according to the International Safe Transit Asso-
ciation standards. The carton must be checked upon
arrivalforexternaldamage.Ifdamageisfound,arequest
for inspection by carrier’s agent must be made in writing
immediately.
The furnace must be carefully inspected on arrival for
damageandboltsorscrewswhichmayhavecomeloose
in transit. In the event of damage the consignee should:
1. Make a notation on delivery receipt of any visible
damage to shipment or container.
2. Notify carrier promptly and request an inspection.
3. With concealed damage, carrier must be notified as
soon as possible - preferably within five days.

5
4. File the claim with the following support documents
within a nine month statute of limitations.
 Original or certified copy of the Bill of Lading, or
indemnity bond:
 Original paid freight bill or indemnity in lieu thereof
 Original or certified copy of the invoice, showing
trade and other discounts or reductions
 Copy of the inspection report issued by carriers
representative at the time damage is reported to
carrier.
The carrier is responsible for making prompt inspection
of damage and for a thorough investigation of each
claim. The distributor or manufacturer will not accept
claims from dealers for transportation damage.
Removal of Existing Furnace
When an existing furnace is removed from a venting
system serving other appliances, the venting system
may be too large to properly vent the remaining at-
tached appliances.
The following steps shall be followed with each appli-
ance remaining connected to the common venting sys-
tem placed in operation, while the other appliances
remaining connected to the common venting system
are not in operation.
(a) Seal any unused openings in the common venting
system.
(b) Visually inspect the venting system for proper size
and horizontal pitch and determine there is no block-
age or restriction, leakage, corrosion and other defi-
ciencies which could cause an unsafe condition.
(c) Insofar as is practical, close all building doors and
windows and all doors between the space in which
the appliances remaining connected to the com-
mon venting system are located and other spaces
of the building. Turn on clothes dryers and any
appliance not connected to the common venting
system. Turn on any exhaust fans, such as range
hoods and bathroom exhausts, so they will operate
at maximum speed. Do not operate a summer ex-
haust fan. Close fireplace dampers.
(d) Follow the lighting instructions. Place the appli-
ance being inspected in operation. Adjust thermo-
stat so appliance will operate continuously.
(e) Test for spillage at the draft hood relief opening
after 5 minutes of main burner operation. Use the
flame of a match or candle, or smoke from a ciga-
rette, cigar, or pipe.
(f) After it has been determined that each appliance
remaining connected to the common venting sys-
tem properly vents when tested as outlined above,
return doors, windows, exhaust fans, fireplace damp-
ers and any other gas burning appliance to their
previous conditions of use.
(g) If improper venting is observed during any of the
above tests, the common venting system must be
corrected in accordance with the latest edition of
the National Fuel Gas Code, ANSI Z223 1.
If resizing any portion of the common venting system,
use the appropriate table in Appendix G in the latest
edition of the National Fuel Gas Code, ANSI Z223.1.
Thermostat Location
In an area having good air circulation, locate the ther-
mostat about 5 feet high on a vibration-free inside wall,
Do not install the thermostat where it may be affected
by:
 drafts or dead spots behind door, in corners or
under cabinets.
 hot or cold air from ducts.
 radiant heat from sun or appliances.
 concealed pipes and chimneys.
 unheated (uncooled) areas behind the thermostat,
such as an outside wall.
Consult the instructions packaged with the thermostat
for mounting instructions.

6
III. Air Requirements
WARNING
Possible death, personal injury or prop-
erty damage may occur if the furnace
and other fuel-burning appliances are
not provided with enough fresh air for
proper combustion and ventilation of flue
gases. Most homes require outside air
to be supplied into the furnace area.
Improved construction and additional insulation in build-
ings has reduced the heat loss, making these buildings
much tighter around doors and windows so air infiltra-
tion is minimal. This creates a problem supplying com-
bustion and ventilation air for gas fired and other fuel
burning appliances. Use of appliances pulling air out of
the house (clothes dryers, exhaust fans, fireplaces,
etc.) increases this problem causing appliances to starve
for air.
Air Requirements
Most homes will require outside air be supplied to the
furnace area by means of ventilation grilles or ducts
connecting directly to the outdoors or spaces open to
the outdoors such as attics or crawl spaces. The follow-
ing information on air for combustion and ventilation is
reproduced from the National Fuel Gas Code NFPA54/
ANSI Z223.1 Section 5.3.
5.3.1 General:
(a) The provisions of 5.3 apply to gas utilization equip-
ment installed in buildings and which require air for
combustion, ventilation and dilution of flue gases from
within the building. They do not apply to (1) direct vent
equipment which is constructed and installed so that all
air combustion is obtained from the outside atmosphere
and all flue gases are discharged to the outside atmo-
sphere, or (2) enclosed furnaces which incorporate an
integral total enclosure and use only outside air for
combustion and dilution of flue gases.
(b) Equipment shall be installed in a location in which
the facilities for ventilation permit satisfactory combus-
tion of gas, proper venting and the maintenance of
ambient temperature at safe limits under normal condi-
tions of use. Equipment shall be located so as not to
interfere with proper circulation of air. When normal
infiltration does not provide the necessary air, outside
air shall be introduced.
(c) In addition to air needed for combustion, process air
shall be provided as required for: cooling of equipment
or material, controlling dew point, heating, drying, oxi-
dation or dilution, safety exhaust, odor control, and air
for compressors.
(d) In addition to air needed for combustion, air shall be
supplied for ventilation, including all air required for
comfort and proper working conditions for personnel.
(e) While all forms of building construction cannot be
covered in detail, air for combustion, ventilation and
dilution of flue gases for gas utilization equipment vented
by natural draft normally may be obtained by applica-
tion of one of the methods covered in 5.3.3 and 5.3.4.
(f) Air requirements for the operation of exhaust fans,
kitchen ventilation systems, clothes dryers, and fire-
places shall be considered in determining the adequacy
of a space to provide combustion air requirements.
5.3.2 Equipment Located in Unconfined Spaces: In
unconfined spaces (see definition below) in buildings,
infiltration may be adequate to provide air for combus-
tion ventilation and dilution of flue gases. However, in
buildings of tight construction (for example, weather
stripping, heavily insulated, caulked, vapor barrier, etc.),
additional air may need to be provided using the meth-
ods described in 5.3.3-b or 5.3.4.
Space, Unconfined. For purposes of this Code, a space
whose volume is not less than 50 cubic feet per 1,000
BTU per hour of the aggregate input rating of all appli-
ances installed in that space. Rooms communicating
directly with the space in which the appliances are
installed through openings not furnished with doors, are
considered a part of the unconfined space.
5.3.3 Equipment Located in Confined Spaces: (a)
All Air from Inside the Building: The confined space
shall be provided with two permanent openings
communicating directly with an additional room(s) of
sufficient volume so that the combined volume of all
spaces meets the criteria for an unconfined space. The
total input of all gas utilization equipment installed in
the combined space shall be considered in making this
determination. Each opening shall have a minimum
free area of 1 square inch per 1,000 BTU per hour of the
total input rating of all gas utilization equipment in the
confined space, but not less than 100 square inches.
One opening shall be within 12 inches of the top and
one within 12 inches of the bottom of the enclosure.
(See Figure 1 ) .
Figure 1
Equipment Located in Confined Spaces;
All Air from Inside Building. See 5.3.3-a
.

7
(b) All Air from Outdoors: The confined space shall be
provided with two permanent openings, one commenc-
ing within 12 inches of the top and one commencing
within 12 inches of the bottom of the enclosure. The
openings shall communicate directly, or by ducts, with
the outdoors or spaces (crawl or attic) that freely com-
municate with the outdoors.
1. When directly communicating with the outdoors,
each opening shall have a minimum free area of 1
square inch per 4,000 BTU per hour of total input
rating of all equipment in the enclosure. (See Fig-
ure 2)
Figure 2
Equipment Located in Confined Spaces;
All Air from OutdoorsInlet Air from
Ventilated Crawl Space and Outlet Air to
Ventilated Attic. See 5.3.3-b
2. When communicating with the outdoors through
vertical ducts, each opening shall have a minimum
free area of 1 square inch per 4,000 BTU per hour
of total input rating of all equipment in the enclo-
sure. (See Figure 3.)
Figure 3
Equipment Located in Confined Spaces;
All Air from Outdoors Through Ventilated
Attic. See 5.3.3-b.
3. When communicating with the outdoors through
horizontal ducts, each opening shall have a mini-
mum free area of 1 square inch per 2,000 BTU per
hour of total input rating of all equipment in the
enclosure. (See Figure 4)
*If the appliance room is located against an outside wall and the air openings communicate
directly with the outdoors, each opening shall have a free area of not less than one square
inch per 4,000 BTU per hour of the total input rating of all appliances in the enclosure.
Figure 4
Equipment Located in Confined Spaces;
All Air from Outdoors. See 5.3.3-b.
4. When ducts are used, they shall be of the same
cross-sectional area as the free area of the open-
ings to which they connect. The minimum dimen-
sion of rectangular air ducts shall not be less than 3
inches.

8
IV. Vent Pipe (All Models) And
Combustion Air Pipe (GUD Models)
Materials
WARNING
Failure to follow these instructions can
result in bodily injury or death from as-
phyxiation. Therefore, carefully read and
follow all instructions given in this sec-
tion.
In order to achieve high efficiency, the products of
combustion from this furnace are cooled to the point
where condensation takes place. Consequently, the vent-
ing must be done in a different manner and with differ-
ent materials than with a conventional system. Two or
three inch PVC Schedule 40 pipe meeting ASTM D1785,
PVC primer meeting ASTM F656 and PVC solvent
cement meeting ASTM D2564 specifications must be
used. Only DWV type fittings meeting ASTM D2665
and ASTM D3311 can be used. Carefully follow the
manufacturers instructions in cutting, cleaning, and sol-
vent cementing of PVC or ABS pipe.
As an alternate to PVC pipe, primer, solvent cement,
and fittings; ABS materials which are in compliance
with the following specifications may be used: two or
three inch ABS Schedule 40 pipe must meet ASTM
D1527 and, if used in Canada, must be CSA listed.
Solvent cement for ABS to ABS joints must meet ASTM
D2235 and, if used in Canada, must be CSA listed. The
solvent cement used for the PVC to ABS transition joint
must meet ASTM D3138. Fittings must be DWV type
fittings which meet ASTM D2661 and ASTM D3311
and, if used in Canada, must be CSA listed. Carefully
follow the manufacturers instructions in cutting, clean-
ing, and solvent cementing PVC or ABS pipes.
WARNING
Solvent cements are combustible liquids
and should be kept away from all igni-
tion sources. (i.e. sparks, open flames
and excessive heat). Avoid breathing ce-
ment vapors or contact with skin and
eyes.
5.3.4 Specially Engineered Installations:
The requirements of 5.3.3 shall not necessarily govern
when special engineering, approved by the authority
having jurisdiction, provides an adequate supply of air
for combustion, ventilation, and dilution of flue gases.
5.3.5 Louvers and Grilles:
In calculating free area in 5.3.3, consideration shall be
given to the blocking effect of louvers, grilles or screens
protecting openings. Screens used shall not be smaller
than 1/4 inch mesh. If the area through a design of
louver or grille is known, it should be used in calculating
the size of opening required to provide the free area
specified. If the design and free area is not known, it
may be assumed that wood louvers will have 20-25
percent free area and metal louvers and grilles will have
60-75 percent free area. Louvers and grilles shall be
fixed in the open position or interlocked with the equip-
ment so that they are opened automatically during
equipment operation.
5.3.6 Special Conditions Created by Mechanical Ex-
hausting or Fireplaces:
Operation of exhaust fans, ventilation systems, clothes
dryers, or fireplaces may create conditions requiring
special attention to avoid unsatisfactory operation of
installed gas utilization equipment.

9
All 90 degree elbows must be medium (1/4 bend DWV)
or long radius (long sweep 1/4 bend DWV) types con-
forming to ASTM D3311. A medium radius (1/4 bend)
elbow is 3-1/16 inch minimum from the plane of one
opening to the centerline of the other opening for 2 inch
pipe (4-9/16 inch for 3 inch pipe).
This furnace must not be connected to any type B, BW,
or L vent or vent connector and must not be vented into
any portion of a factory built or masonry chimney,
except when used as a pathway for PVC pipe as de-
scribed below
Flexible couplings for joining PVC pipe (sometimes
called no hub connectors) have been used by some
installers to connect the field supplied portion of the
vent system to the furnace. Amana Refrigeration, Inc.
does not encourage nor recommend using these con-
nectors. However, if you do choose to use no-hub
connectors, the connectors must be gas tight, water
tight, and able to withstand continuous exposure to the
warm, moist, acidic flue products of the furnace.
It is the responsibility of the installer to follow the manu-
facturers recommendations and to verify that all flue
pipe connectors used are compatible with the furnace
flue products. In addition the connectors must possess
adequate structural integrity to prevent flue pipe sepa-
rations during furnace operation.
V. Vent Piping - GUX (All
Installations), GUC (All Installations),
and GUD (One Pipe Installations)
IMPORTANT: The length of the vent pipe affects the
performance of the furnace and therefore must be care-
fully sized.
Pipe Diameter for GUC (All Models), GUX (All Models)
and GUD045 (One Pipe) Venting
# of Inside
Elbows
5 to
10 feet
10 to
15 feet
15 to
20 feet
20 to
25 feet
25 to
30 feet
30 to
35 feet
35 to
40 feet
1 2"2" 2" 2"2"2" 2"
2 2"2" 2" 2"2"2" 2"
3 2"2" 2" 2"2"2" 3"
4 2"2" 2" 2"2"3" 3"
Pipe Diameter for GUD070, GUD090 and GUD115
(One Pipe) Venting
# of Inside
Elbows
5 to
10 feet
10 to
15 feet
15 to
20 feet
20 to
25 feet
25 to
30 feet
30 to
35 feet
35 to
40 feet
1 3"3" 3" 3"3"3" 3"
2 3"3" 3" 3"3"3" 3"
3 3"3" 3" 3"3"3" 3"
4 3"3" 3" 3"3"3" 3"
The inside feet of straight pipe and inside elbows repre-
sent the venting system from the furnace to the inside
wall. Follow termination instructions for going from the
inside wall to the outside in the next paragraph.
When the vent pipe goes through an outside wall, the
vent must terminate at least one foot outside to keep
moist combustion products away from the structure.
The vent termination must be at least three feet above
any forced air inlet located within ten feet. It must be at
least four feet below, four feet horizontally from or one
foot above any door, window, or gravity air inlet into any
building. The vent must terminate at least one foot
above ground level. If heavy snow is expected locally,
this distance may need to be increased. The vent shall
not terminate over public walkways, or over an area
where condensate or vapor could create a nuisance or
hazard or could be detrimental to the operation of regu-
lators, relief valves, or other equipment. Drill a 2-3/8
inch diameter hole through the wall for 2 inch pipe. (For
3 inch pipe, drill a 3-1/2 inch diameter hole.) Cut a piece
of PVC (ABS) pipe that is the thickness of the wall plus
the depth of the sockets of the fittings to be installed on
the inside and outside of the walls. To prevent the vent
pipe from moving and possibly damaging connections,
locate the fitting on the inside wall and a coupling on the
outside wall as shown in Fig. 5. To prevent condensate
from freezing inside the PVC flue pipe in extremely cold
conditions or in long outdoor runs, insulation may be
required on the cut side of the PVC pipe. Use 1/2 inch
thickness closed cell foam insulation such as Armaflex
or Insultube.

10
Additional Canadian Venting
Requirements
In Canada venting shall conform to the requirements
of the current CANI-B149 Installation Codes.
Use only C.S.A. Listed 2 inch or 3 inch nominal diam-
eter PVC or ABS pipe and fittings throughout.
The Minimum vent consists of 3 feet of straight pipe
with 2 elbows (9 equivalent feet).
A single wall vent shall not be run vertically through
the roof. The vent may be run through an existing
unused chimney as described in the previous venting
section provided the space between the vent pipe and
the chimney is insulated and closed with a weather
tight, corrosion resistant flashing.
Cut all vent pipe at right angles. Remove inside and
outside burr at each cut. Use cleaner to clean pipe
and fitting socket. Use CSA listed cement to fasten
pipe and fittings.
Follow manufacturers cleaning and cementing instruc-
tions carefully to avoid leakage.
NOTE: ALL PIPING EXPOSED OUTDOORS OR IN
UNHEATED AREAS MUST BE INSULATED WITH
1/2 inch THICK CLOSED CELL FOAM INSULATION
SUCH AS ARMAFLEX OR INSULTUBE.
The vent terminal shall not be located:
1. Less than 12 inches above the finished grade line.
2. Less than 36 inches from any building opening or
any gas service regulator. (For gas service regula-
tors in the Province of Ontario, 72 inches.)
3. Less than 72 inches from the combustion air inlet of
another appliance.
4. Directly above a gas utility meter or service regula-
tor.
5. Over a walkway unless 84 inches above grade.
Figure 5
Horizontal Vent Termination
In a basement installation, the vent pipe may be run
between the joist spaces. If the vent must go below the
joists, then the pipe must run up into the last joist space
to go through the header. Two 45° elbows should be
used rather than 90s. The horizontal run must not have
any sag that can hold condensate and should pitch up at
least 1/4 inch per foot so that condensate will run back
to the unit to drain. Support the horizontal run at least
every three feet. Allow for some expansion and con-
traction from temperature fluctuations. The normal di-
rection changes usually account for this, but if you have
a long run followed by a short offset of less than 40
inches such as going up into the last joist space, the
pipe should be tightly clamped to prevent flex loading
on the fittings. Seal around the pipe on the outside wall
with silicone caulking material.
If the vent is to be run vertically through the roof, it must
extend at least 12 inches above the roof line and shall
be at least 12 inches from any vertical wall. It must
terminate at least three feet above any forced air inlet
located within 10 feet, and at least 12 inches from any
door, window, or gravity air inlet into any building. If
heavy snow is expected to remain on the roof, the
clearances to vertical walls and the roof may need to be
increased. The vent must be made tight where it pen-
etrates the roof with a proper flashing such as used with
a plastic plumbing vent. The vent may be run through
an existing unused chimney: however, the pipe must
be used all the way through to at least 12 inches above
the top of the existing chimney. The space between the
vent pipe and the chimney must be closed with a weather
tight, corrosion resistant flashing. Never vent with an
existing appliance or vent used by a solid fuel appliance.
WARNING
Upon completion of the furnace installa-
tion, carefully inspect the entire flue sys-
tem both inside and outside the furnace
to assure it is properly sealed. Leaks in
the flue system can result in serious per-
sonal injury or death due to exposure to
flue products, including carbon monox-
ide.

11
VI. Combustion Air And Vent Piping
(GUD - Two Pipe)
General Information And Safety
Precautions
WARNING
Failure to follow these instructions can
result in bodily injury or death from as-
phyxiation. Therefore, carefully read and
follow all instructions given in this sec-
tion.
CAUTION
Terminate the combustion air intake as
far as is practical from the air condition-
ing unit or heat pump, swimming pools,
swimming pool pumping units, and dryer
vents.
All combustion air and exhaust piping must be installed
in accordance with local codes and these instructions.
When the furnace is installed in a confined space where
the minimum clearances to combustible surfaces (see
Specification Sheet) are applied, such as in a closet or a
utility room, two ventilation openings are required with a
total minimum free area of 0.25 square inches per
1,000 BTUH of the furnace input rating. One opening
must be within 12 inches of the top and one must be
within 12 inches of the bottom of the confined space. In
typical construction, the clearance between the door
and door frame will usually be adequate to satisfy this
ventilation requirement.
When the GUD furnace is installed in the same space
with other gas appliances, such as a water heater, make
sure there is an adequate supply of combustion and
ventilation air for the other appliances. See the latest
edition of the National Fuel Gas Code (ANSI 7793.1) for
determining the combustion air requirements for the
appliances.
The GUD furnaces are supplied with a 3 inch air intake
terminal screen. This screen is shipped in the same
plastic sack that held this manual. For both vertical and
horizontal installations, insert the screen into the air
intake terminal until it is firmly secured at the hub of the
terminal elbow.
If the vent (flue) pipe is exposed to extremely cold
temperatures and/or long runs through unheated spaces
or outdoors, insulation may be required on the outside
of the vent pipe to prevent condensate from freezing.
Canadian installers must take note of the Additional
Canadian Venting Requirements in this section. Where
required, use 1/2 inch thick closed cell foam insulation
such as Armaflex or Insultube.
NOTE: Inspect the flue for leaks before installing any
insulation.
If the combustion air pipe is to be installed above a
suspended ceiling or other area where dripping of con-
densation will be objectionable, insulation of the com-
bustion air pipe may be required. Where required, use
1/2 inch thick closed cell foam insulation such as
Armaflex or Insultube.
Location of Exhaust And Intake
Terminations
All Installations
This furnace can be installed with either a vertical or
horizontal direct vent. In either case, the exhaust vent
and the combustion air intake pipe must be located on
the same side of the structure and separated by no less
than 3 inches and no more than 24 inches.
This ensures enough distance to prevent flue gas recir-
culation and limits the distance to ensure the vent outlet
and air inlet terminals are in the same atmospheric
pressure zone.
The following points must also be considered when
installing the vent pipe in either a horizontal or vertical
application:
1. The vent termination must be at least 3 feet above
any forced air inlet located within 10 feet.
Exception: This provision shall not apply to the
combustion air intake of a direct vent furnace.
2. The vent termination must be at least 12 inches
from any door, window, or gravity air inlet into any
building.
3. The vent must terminate at least 2 feet above
ground level or roof level. If heavy snow accumula-
tion is expected, this distance will need to be in-
creased.
4. The vent shall not terminate over public walkways
or over an area where condensate or vapor could
create a nuisance or hazard or could be detrimental
to the operation of regulators, relief valves, or other
equipment.
5. In addition, the combustion air intake should not be
terminated in areas that are frequently very dusty or
dirty.

12
CAUTION
Do not terminate the combustion air in-
take where the air is often heavily con-
taminated with compounds containing
chlorine or fluorine. Common residen-
tial sources of such compounds include:
 Swimming pools and swimming pool
pumps/filter
 Clothes dryer vents
 Remote air conditioning or heat pump
units (A refrigerant leak would con-
taminate the combustion air.)
 Plumbing vent stacks
 Bathroom or swimming pool exhaust
fans
 Undried paint strippers, adhesives,
paints, varnishes, sealers, waxes, and
solvents. These are often used during
new construction or remodeling.
Various commercial and industrial pro-
cesses may also be sources of chlorine/
fluorine compounds.
Horizontal Vent/Intake Terminations
90°
Medium
Radius
Elbow
Vent
12" Min.
24" Max.
3" Min.
Screen
12" Min.
Air Intake
24" Max.
Figure 6
Horizontal Vent Termination
Position the combustion air intake terminal away from
obstructions, above anticipated snow accumulations,
and at least 12 inches above grade, as shown in Figure
6.
The exhaust vent must penetrate the wall within the
shaded region as shown in Figure 6.
All exhaust vent and air intake terminal fittings must be
medium radius (1/4 bend DWV) 90 degree elbows.
To prevent unnecessary shutdown of furnace due to
pressure switch trips, always determine anticipated snow
accumulation level, and install the terminals accord-
ingly to prevent exhaust vent and air intake blockages
If installation above snow accumulation is required, add
additional elbows as shown in Figure 7. A 12 inch
minimum clearance between the air intake and the
highest anticipated snow level must be maintained. The
exhaust vent must penetrate the wall within the shaded
region as shown in Figure 7.
90°
Medium Radius
Elbow
12" Min.
Vent
24" Max.
3" Min.
12" Min. Above
Highest Anticipated
Snow Level
Air Intake
24" Max.
Screen
12" Min.
Figure 7
Horizontal Vent Termination Above
Anticipated Snow Level
Do not point terminals into window wells, stairwells,
alcoves or other recessed areas. It is preferable for the
air intake to terminate on opposite or adjacent sides of
the structure from the dryer vent. If this is not practical,
maintain a 3 foot clearance (residential laundry) or a 10
foot clearance (commercial laundry).
Vertical Vent/lntake Terminations
If the vent and air intake pipes are to be run vertically
through the roof, they must extend at least 12 inches
above the roof line and shall be no closer than 12 inches
to any vertical wall. The vent pipe must extend at least
12 inches above the air intake. See Figure 8. In areas
where heavy snow accumulation is expected, these
distances will need to be increased. The vent and air
intake pipes must be made tight where they pass through
the roof with a proper flashing such as used with a
plastic plumbing vent.
Maintain at least a three foot clearance from the air
intake pipe to plumbing vent stacks.

13
90°
Medium Radius
Elbow
12" Min.
Vent
24" Max.
3" Min.
Air Intake
12" Min.
Figure 8
Vertical Vent Termination
The vent and air intake pipe may be run through an
existing unused chimney. However, the pipes must be
run all the way through the chimney, with the air intake
pipe terminating at least 12 inches above the top of the
chimney.
See Figure 9 for explanation. The flue pipe must termi-
nate at least 12 inches above the air intake. The air
intake and exhaust may run side by side or as far apart
as necessary within the chimney.
The open space around the two pipes must be closed
with a weather tight, corrosion resistant flashing. NEVER
VENT WITH AN EXISTING APPLIANCE OR A VENT
USED BY A SOLID FUEL APPLIANCE.
Two 90° Medium
Radius Elbows
Air
Intake
Screen
12"
12"
Vent
Figure 9
Venting Through Existing Chimney
Vent/lntake Terminations For Installation
of Multiple Direct Vent Furnaces
If more than one direct vent furnace is to be installed
vertically through a common roof top, maintain the
same minimum clearances between the exhaust vent
and air intake terminations of adjacent units as with the
exhaust vent and air intake terminations of a single unit
(Figure 8).
If more than one direct vent furnace is to he installed
horizontally through a common side wall, maintain the
clearances as shown in Figure 10. Always terminate all
exhaust vent outlets at the same elevation and always
terminate all air intakes at the same elevation.
90°
Medium Radius
Elbows
12" Min.
Vents
24" Max.
3" Min.
Air Intakes
24" Max.
24" Max.
3" Min.
3" Min.
Figure 10
Horizontal Venting Of Multiple Units
Sizing Of Exhaust Vent And Combustion
Air Inlet Pipes
Consult Tables 1 to 4 to select the proper diameter
exhaust and combustion air piping. The vent and air
intake piping is sized for each unit model number based
on inside piping length and number of inside 90° elbows
required. Two 45° elbows are equivalent to one 90°
elbow. For all piping, the elbow(s) used for vent & air
pipe termination outside the structure as shown in Fig-
ures 6, 8, and 9 are not to be counted when using
Tables 1 through 4. The additional two 90° elbows as
shown in Figure 7 must be counted as part of the total
number of inside elbows when using Tables 1 - 4.
WHEN THE VENT SYSTEM REQUIRED IS BORDER-
LINE WITH NEXT SIZE COMBINATION CATEGORY,
USE THE NEXT LARGER SIZE.
IMPORTANT: One short radius 90° elbow is equivalent
to 3-1/3 medium radius elbows. For this reason, short
radius 90° elbows must not be used. The proper
centerline-to-centerline dimensions for medium radius
90° elbows are shown below in Figure 11.
Elbow or
Coupling
Inside Wall
90° Elbow
Outside To Ground
12" Min.
3-1/16" Min. For 2" Pipe
4-9/16" Min. For 3" Pipe
Figure 11
Medium Radius Elbow Dimensions

14
EXAMPLE:
An installation calls for a 45,000 Btuh furnace. It must
be vented 35 inside feet and use two inside medium
radius 90° elbows on both inlet and exhaust. With this in
mind, we must look at Table 1 to determine the correct
vent and air intake pipe size. With two elbows and 35
feet of straight pipe, 3 inch air intake pipe must be used
and 2 inch vent pipe.
45,000 BTUH Furnace
No. Of Vent Inside Feet Of Straight Pipe Each Run
Elbow s Type 5 - 10 10 - 15 15 - 20 20 - 25 25 - 30 30 - 35 35 - 40
1Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
2
3
2
2Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
2
3
2
3Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
2
3
2
4Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
2
3
2
Table 1
IMPORTANT: When three inch diameter exhaust pipe
is used, the transition from two inch to three inch pipe
must be made in a vertical run. This is necessary for
proper condensate drainage and pressure switch opera-
tion.
70,000 BTUH Furnace
No. Of Vent Inside Feet Of Straight Pipe Each Run
Elbow s Type 5 - 10 10 - 15 15 - 20 20 - 25 25 - 30 30 - 35 35 - 40
1Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
2
3
2
2Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
2
3
2
3Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
2
3
3
4Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
3
3
3
Table 2
90,000 BTUH Furnace
No. Of Vent Inside Fee t Of Straight Pipe Each Run
Elbow s Type 5 - 10 10 - 15 15 - 20 20 - 25 25 - 30 30 - 35 35 - 40
1Inlet
Outlet
3
2
3
2
3
2
3
2
3
2
3
3
3
3
2Inlet
Outlet
3
2
3
2
3
2
3
2
3
3
3
3
3
3
3Inlet
Outlet
3
2
3
2
3
2
3
2
3
3
3
3
3
3
4Inlet
Outlet
3
2
3
2
3
2
3
3
3
3
3
3
3
3
Table 3
115,000 BTUH Furnace
No. Of Vent Inside Feet Of Straight Pipe Each Run
Elbow s Type 5 - 10 10 - 15 15 - 20 20 - 25 25 - 30 30 - 35 35 - 40
1Inlet
Outlet
3
3
3
3
3
3
3
3
3
3
3
3
3
3
2Inlet
Outlet
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3Inlet
Outlet
3
3
3
3
3
3
3
3
3
3
3
3
3
3
4Inlet
Outlet
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Table 4
Vent Pipe Installation
The size of the vent and air intake pipes is determined
by the heating capacity of the furnace and the length
and number of elbows of the pipe runs. To properly size
the pipes, refer to the previous section.
Use only the fittings, primer, and solvent cement which
are described in previous section. An air intake screen
(as described in previous section) must be installed.
This screen is supplied with the furnace. Do not place a
screen in the exhaust vent termination. It is not needed,
and the furnace flue products could cause it to corrode.

15
VII. Condensate Piping
Figure 12
Standpipe Assembly
The Air Command 90 and 95 achieves its high effi-
ciency by condensing some of the flue products into a
slightly acidic water which must be piped to a drain. A
standpipe, which is shipped with the furnace, must be
installed on the right side of the furnace cabinet (Figure
12). The condensate from the recuperative coil and the
induced draft blower flows into this standpipe which acts
as a trap. No other trap may be used. A 3/4 inch PVC or
CPVC pipe must be run from the side of the standpipe
to a drain, maintaining a horizontal downward slope in
accordance with good plumbing practices. Do not trap
this line.
PVC or CPVC pipe is recommended since it is corro-
sion resistant, rigid, and not easily damaged. The drain
line must not be routed outside where it could freeze
and become blocked. The top of the standpipe must be
left open so any blockage in the drainline will be re-
lieved out the tip of the standpipe and not back up into
the unit.
If an air conditioning coil is installed with the furnace, a
common drain may be used (install as shown in Figure
13). Leaving an open tee near the cooling coil will allow
positive air pressure in the supply air plenum be relieved
outtheteewithoutinterferingwithdrainingofthefurnace
condensate.
Figure 13
WARNING
To prevent death, personal injury or prop-
erty damage, solvent cements are com-
bustible liquids and should be kept away
from all ignition sources. (ie. sparks, open
flames and excessive heat). Avoid breath-
ing cement vapors or contact with skin
and eyes.
Under some conditions, insulation of some or all of the
vent pipe and/or combustion air pipe may be required.
Do not install insulation until after the flue system has
been inspected for leaks as described below.
WARNING
To prevent death, personal injury or prop-
erty damage due to carbon monoxide,
carefully inspect the entire flue system
both inside and outside the furnace after
installation is completed, to assure it is
properly sealed and not leaking flue
gases.
For each 2 inch pipe, drill a 2-3/8 inch diameter hole
through the wall at the proper location.
For each 3 inch pipe, drill a 3-1/2 inch diameter hole
through the wall at the proper location.
Cut a piece of PVC (ABS) pipe that is the thickness of
the wall plus the depth of the sockets of the fittings to be
installed on the inside and outside of the walls.
To prevent the vent pipe from moving, and possibly
damaging the connections, locate the fittings on the
inside wall and the elbow on the outside as shown in
Figure 11 for the air intake.
In a basement installation, the pipes may be run be-
tween the joist spaces. If the pipes must go below the
joists, then the pipes must run up into the last joist
space to go through the header. Two 45° elbows should
be used rather than 90s. The horizontal run of exhaust
pipe must not have any sag that can hold condensate
and should reach up at least 1/4 inch per foot so that
condensate will run back to the unit to drain. Support
the horizontal run at least every three feet.
Allow for some expansion and contraction from tem-
perature fluctuations. The normal direction changes
usually account for this, but if you have a long run
followed by a short offset of less than 40 inches such as
going up into the last joist space, the pipes should be
tightly clamped to prevent flex loading on the fittings.
Seal around the pipe on the outside wall with silicone
caulking material.

16
VIII. Gas Piping
The rating plate is stamped with the model number, type
of gas and gas input rating. Make sure the furnace is
equipped to operate on the type of gas available.
Inlet Gas Pressure
Natural Min. 5.0" W.C., Max. 10.0" W.C.
Propane Min. 11.0" W.C., Max. 13.0" W.C.
Inlet gas pressure must not exceed the maximum value
shown in table above.
The minimum supply pressure must be maintained to
prevent unreliable ignition. In addition, gas input to the
burners must not exceed the rated input shown on the
rating plate. Overfiring the furnace could result in prema-
ture heat exchanger failure.
High Altitude Derate (U.S. Installations Only)
When this furnace is installed at altitudes above 2,000
feet above sea level the furnace input must be derated 4
percent for each 1,000 feet above sea level because the
density of the air is reduced.
Insomeareasthegassupplierwillderatethegasatarate
of 4% for each 1,000 feet above sea level. It this is not
done, smaller orifices will be required at altitudes above
3,500 feet (nonderated natural gas) or 4,500 feet
(nonderated propane gas).
A different pressure switch is required at altitudes more
than 4,000 feet above sea level. This is required regard-
less of the heat content of the fuel used.
Highaltitudekits arepurchasedaccording tothealtitude
and usage of either propane gas or natural gas. Refer to
the Amana distributor for required high altitude kit(s).
Do not derate the furnace by adjusting the manifold
pressure to a lower pressure than specified on the
furnace nameplate. With a lower air density and a lower
manifoldpressure attheburnerorifice,the orificewillnot
supply the proper amount of air into the burner, causing
incomplete combustion of the gas, flashback, and pos-
sible yellow tipping.
Gas Piping
IMPORTANT NOTE: To avoid possible unsatisfactory
operation or equipment damage due to underfiring of
equipment, do not undersize the natural/propane gas
piping from the meter/tank to the furnace. Include all
appliances which may be operated simultaneously when
sizing a trunk line.
The gas pipe supplying the furnace must be properly
sized based on gas flow required, specific gravity of the
gas and length of the run. The gas line installation must
comply with local codes, or in the absence of local
codes, with the latest edition of the National Fuel Gas
Code ANSI Z223.1.
Natural Gas Capacity of Pipe
In Cubic Feet of Gas Per Hour (CFH)
Length of Nominal Black Pipe Size
Pipe in Feet 1/2" 3/4" 1" 1 1/4" 1 1/2"
10 132 278 520 1050 1600
20 92 190 350 730 1100
30 73 152 285 590 980
40 63 130 245 500 760
50 56 115 215 440 670
60 50 105 195 400 610
70 46 96 180 370 560
80 43 90 170 350 530
90 40 84 160 320 490
100 38 79 150 305 460
(Pressure 0.5 psig or less and pressure drop of 0.3" W.C.; Based on
0.60 Specific Gravity Gas)
CFH = BTUH Furnace Input
Heating Value of Gas (BTU/Cubic Foot)
Connecting Gas Piping - Natural Gas
Refer to Figure 14 for the general layout at the furnace.
The following rules apply:
1. Use black iron or steel pipe and fittings for the
building piping.
2. Use pipe joint compound on male threads only.
Pipe joint compound must be resistant to the action
of the fuel used.
3. Use ground joint unions.
4. Install a drip leg to trap dirt and moisture before it
can enter the gas valve. The drip leg must be a
minimum of three inches long.
5. A 1/8 inch NPT pipe plug fitting, accessible for test
gage connection, must be installed immediately
upstream of the gas supply connection to the fur-
nace.
6. Use two pipe wrenches when making connection to
the gas valve to keep it from turning. The orienta-
tion of the gas valve on the manifold must be the
same as shipped from the factory.
7. Within six feet of the unit, install a manual shutoff
valve between the meter and the unit. If a union is
installed, the union must be downstream of the
manual shutoff valve, between the shutoff valve
and the furnace.
8. Tighten all joints securely.
9. The furnace must be connected to the building
piping by one of the following:
Rigid metallic pipe and fittings.
Semirigid metallic tubing and metallic fittings.
Aluminum alloy tubing must not be used in exte-
rior locations.
Listed gas appliance connectors, used in accor-
dance with the terms of their listing, must be
completely in the same room as the furnace.

17
A ground joint union, drip leg, and manual shutoff valve
must also be supplied by the installer. In some cases,
the installer may also need to supply a transition piece
from 1/2" to another pipe size.
When the gas piping enters through the right side of the
furnace (Figures 16 and 17) the installer must supply the
straight pipe to reach the exterior of the furnace.
Figure 16
Gas Inlet Through Furnace Right Side
(Except GUD)
Figure 17
Gas Inlet Through Furnace Right Side
(GUD Only)
A ground joint union, drip leg, and manual shutoff valve
must also be supplied by the installer. In some cases,
the installer may also need to supply a transition piece
from 1/2 inch to another pipe size.
The connectors or semirigid tubing must be pro-
tected against physical and thermal damage when
installed. Aluminum-alloy tubing and connectors
must be coated to protect against external corro-
sion when in contact with masonry, plaster or
insulation or are subject to repeated wettings by
such liquids as water (except rain water), deter-
gents or sewage.
Figure 14
When the gas piping enters through the left side of the
furnace (Figure 15), the installer must supply the follow-
ing fittings (starting from the gas valve):
90 degree elbow
1-1/2 inch close nipple
90 degree elbow
Straight pipe to reach exterior of furnace
Figure 15
Gas Inlet Through Furnace Left Side
(Except GUD)

18
When the gas piping enters through the top of the fur-
nace (Figure 18), the installer must supply the following
fittings (starting from the gas valve):
90 degree elbow
1-1/2 inch close nipple
90 degree elbow
Straight pipe to reach exterior of furnace
Figure 18
Gas Inlet Through Furnace Top Side
(GUD)
A ground joint union, drip leg, and manual shutoff valve
must also be supplied by the installer. In some cases,
the installer may also need to supply a transition piece
from 1/2 inch to another pipe size.
Checking Gas Piping
CAUTION
To prevent personal injury or property
damage due to fire, the following instruc-
tions must be performed regarding gas
connections, pressure testing, location
of shutoff valve and installation of gas
piping.
 Before placing in operation, leak test the unit and
gas connections. To avoid the possibility of ex-
plosion or fire, never use a match or open flame
to test for leaks. Never exceed specified pres-
sures for testing. Higher pressure may damage
the gas valve and cause overfiring, resulting in
heat exchanger failure.
 This unit and shutoff valve must be disconnected
from the gas supply piping system before supply
piping system pressure testing with test pressures
in excess of 1/2 psig (3.48 kPa).
 This unit must be isolated from the gas supply
system by closing its manual shutoff valve before
pressure testing of gas supply piping system with
test pressures equal to or less than 1/2 psig (3.48
kPa).
Tanks and Piping - Propane Gas Units
WARNING
To prevent death, personal injury or prop-
erty damage due to fire or explosion
caused by a propane gas leak, install a
gas detecting warning device. Since rust
can reduce the level of odorant in pro-
pane gas, a gas detecting warning de-
vice is the only reliable way to detect a
propane gas leak. Contact a local pro-
pane gas supplier about installing a gas
detecting warning device.
All propane gas equipment must conform to the safety
standards of the National Board of Fire Underwriters
(See NBFU Manual 58).
For satisfactory operation, propane gas pressure must
be 10 inch W.C. at the furnace manifold with all gas
appliances in operation. Maintaining proper gas pres-
sure depends on three main factors:
1. Vaporization rate, depending on temperature of the
liquid, and wetted surface area of the container or
containers.
2. Proper pressure regulation. Two-stage regulation is
recommended for both cost and efficiency.
3. Pressure drop in lines between regulators, and be-
tween second stage regulator and the appliance.
Pipe size will depend on length of pipe run and total
load of all appliances.
Complete information regarding tank sizing for vaporiza-
tion, recommended regulator settings, and pipe sizing
is available from most regulator manufacturers and
propane gas suppliers.
Since propane gas will quickly dissolve white lead or
most standard commercial compounds, special pipe
dope must be used. Shellac base compounds resistant
to the actions of liquefied petroleum gases such as
Gasolac, Stalactic, Clydes or John Crane are satisfac-
tory.
Refer to Figure 19 for typical propane gas installations.

19
Figure 19
Propane Gas Piping Charts
Sizing Between First and Second Stage Regulator
Maximum Propane Capacities listed are based on 2 psig pressure drop at 10 psig setting.
Capacities in 1,000 BTU/hour.
Pipe or Nominal Pipe Size
Tubing Tubing Size, O.D. Type L Schedule 40
Length, 3/8" 1/2" 5/8" 3/4" 7/8" 1/2" 3/4"
Feet
10 730 1,700 3,200 5,300 8,300 3,200 7,500
20 500 1,100 2,200 3,700 5,800 2,200 4,200
30 400 920 2,000 2,900 4,700 1,800 4,000
40 370 850 1,700 2,700 4,100 1,600 3,700
50 330 770 1,500 2,400 3,700 1,500 3,400
60 300 700 1,300 2,200 3,300 1,300 3,100
80 260 610 1,200 1,900 2,900 1,200 2,600
100 220 540 1,000 1,700 2,600 1,000 2,300
125 200 490 900 1,400 2,300 900 2,100
150 190 430 830 1,300 2,100 830 1,900
175 170 400 780 1,200 1,900 770 1,700
200 160 380 730 1,100 1,800 720 1,500
To convert to capacities at 15 psig settings - multiply by 1.130
To convert to capacities at 5 psig settings - multiply by 0.879
Sizing Between Single or Second Stage Regulator and Appliance*
Maximum Propane Capacities Listed are Based on 1/2" W.C. pressure drop at 11" W.C. setting.
Capacities in 1,000 BTU/hour.
Pipe or Nominal Pipe Size
Tubing Tubing Size, O.D. Type L Schedule 40
Length, 3/8" 1/2" 5/8" 3/4" 7/8" 1-1/8" 1/2" 3/4" 1" 1-1/4" 1-1/2"
Feet
10 39 92 199 329 501 935 275 567 1,071 2,205 3,307
20 26 62 131 216 346 630 189 393 732 1,496 2,299
30 21 50 107 181 277 500 152 315 590 1,212 1,858
40 19 41 90 145 233 427 129 267 504 1,039 1,559
50 18 37 79 131 198 376 114 237 448 913 1,417
60 16 35 72 121 187 340 103 217 409 834 1,275
80 13 29 62 104 155 289 89 185 346 724 1,066
100 11 26 55 90 138 255 78 162 307 630 976
125 10 24 48 81 122 224 69 146 275 567 866
150 9 21 43 72 109 202 63 132 252 511 787
200 8 19 39 66 100 187 54 112 209 439 665
250 8 17 36 60 93 172 48 100 185 390 590
*Data in accordance with NFPA pamphlet NO. 54
WARNING
To prevent death, serious personal in-
jury or property damage due to fire or
explosion caused by a propane gas leak,
install a gas detecting warning device.
If the propane gas furnace is installed in
a basement, an excavated area or a con-
fined space, a warning device is required
due to:
 Propane gas is heavier than air and
any leaking gas can settle in any low
areas or confined spaces.
 Propane gas odorant may fade, mak-
ing the gas undetectable except with
a warning device.
If the presence of gas is suspected, fol-
low the instructions on Page 2 of this
manual.

20
The ground wire should run all the way back to the
electrical panel. To confirm proper grounding:
1. Disconnect electrical power.
2. Measure resistance between the neutral (white) con-
nection and one of the burners.
3. Resistance should be 10 ohms or less.
On all units except GUD models, line voltage wiring
must enter through the left side of the furnace. On GUD
models, line voltage wiring must enter through the top or
left side of the furnace. Connect hot, neutral, and ground
wires as shown in the wiring diagram located on the
blower door of the unit. The ground screw is located
inside the junction box. (Figure 20)
Ground
Screw
Line
Voltage
Connections
Figure 20
Field Wiring Connections - GUD
(Line Voltage)
(Shown with Junction Box Cover Removed For
Clarity Only)
lX. Electrical Wiring
WARNING
To avoid the risk of electrical shock,
wiring to the unit must be properly po-
larized and grounded.
WARNING
To avoid electrical shock, injury or death,
disconnect electrical power before
changing any electrical wiring.
CAUTION
Label all wires prior to disconnection
when servicing controls. Wiring errors
can cause improper and dangerous op-
eration. After servicing is completed, al-
ways verify proper operation.
The wiring harness on this unit is furnished as an inte-
gral part of the furnace. Field alteration to comply with
electrical codes should not be required.
Line Voltage Wiring
Power supply to the furnace must be N.E.C. Class 1,
and must comply with all applicable codes. The furnace
must be electrically grounded in accordance with the
local codes or, in their absence, with the latest edition of
the National Electrical Code, ANSI NFP No. 70 and/or
the CSA C22. 1 Electrical Code. A fused disconnect
should be provided and sized in accordance with the
unit maximum overcurrent protection.