
Use and Care Instructions
For
Gas Downflow Furnace
If not installed, operated, and maintained in
accordance with the manufacturer's instructions,
this product could expose you to substances in
fuel or from fuel combustion which are known to
the State of California to cause cancer, birth
defects or other reproductiv e harm. Also,
operation, installation and servicing of this
product could expose you to airborne particles of
glasswool fibers known to the State of California
to cause cancer through inhalation.
035--15875--301 (1198)
DLAS MODELS
(No Coil Cabinet)
FORYOURSAFETY--Donotstoreoruseflammable liquids, vapors, or materials in the immediate
area near the furnace or other heating appliance.
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, perĆ
sonal injury or loss of life. Installation and service
must be performed by a qualified installer, service
agency or the gas supplier.
Never attempt to modify this furnace. Fire, exploĆ
sion, or asphyxiation may result. If malfunction ocĆ
curs, obtain the assistance of a qualified service
agent.
DGAM, DGAT & DGPT MODELS
(With Built--in Coil Cabinet)
Before placing furnace in service, it must be
checked to make sure it is equipped for the
type of gas being used. The burner flame
must also be observed andadjusted if necesĆ
sary. Failure to observe this caution may reĆ
sult in unsafe operation, explosion, and/or
fire or asphyxiation. See sections Gas SupĆ
ply" and Combustion Air".
Use of furnace or air conditioning components
that are not included in the Underwriter's LabĆ
oratories certification of this appliance may
create a hazard, will invalidate the certificaĆ
tion, and will in many states make installation
illegal. UL listed air conditioning components
arespecifiedonthefurnacelabel.

WARRANTY AND
RESPONSIBILITIES
It is the sole responsibility of the home
owner to make certain that the gas
furnace has beencorrectly set upand
converted to the proper fuel (Propane
or Natural gas) and adjusted to operate properly.
The manufacturer warrants the furnace to be free fromdefectsinmaterial or workmanship for the stated time
in the warranty agreement (see warranty certificate packed with the furnace).
However, the manufacturer will not be
responsible for any repair costs to
correct problems due to improper
set--up, improper installation, furnace
adjustments, improper operating procedure by the user, etc.
Some specific examples of service
calls which cannot be included in warranty payments are:
1. Converting the furnace to use
another type of gas.
2. Correcting faulty duct work in the
home.
3. Correcting wiring problems in the
electrical circuit to the furnace.
4. Resetting circuit breakers or other switches.
5. Adjusting the burner air shutter or
service calls made to correct
problems caused by improper air
adjustment.
6. Correcting problems caused by
improper gas supply pressure to
the furnace.
7. Instructional training on how to
light and operate furnace.
8. Furnace problems caused by installation of air conditioner, heat
pump, or other air quality device
which is not approved.
9. Problems caused by improper installation of the furnace flue assembly (roof jack).
10. Adding a roof jack extension
because of unusual wind conditions or snow conditions.
11. Adjusting or calibrating the thermostat.
12. Construction debris which has
fallen into the flue or combustion
air openings.
You should establish a firm understanding of these responsibilities with
your manufactured housing dealer,
serv ice company or gas supplier so
there will be nomisunderstanding at a
later time.
GAS SUPPLY
The gas supply to your home will either be Natural Gas or Propane gas
(bottle gas). Your furnace will be factory equipped to operate on only one
of these two different gases.
A small metal tag secured to the furnace next to the gas valve will specify
thetypeofgasyourfurnaceis
equipped to use.
If the gas is different from that specified on the metal tag, the furnace can
be converted by following the instructions on the furnace safety label
inside lower front panel. P arts for conversion are contained in the small
cloth bag attached to the gas valve.
Be sure the proper size orifice is used,
as specified on the furnace name
plate.
The furnace must be conĆ
verted by a qualified techniĆ
cian. Improper conversion
can cause unsafe operation,
explosion, and/or fire or asĆ
phyxiation.
Natural Gas Operation
The furnace is designed for 7” W.C.
inlet pressure. Pressure is reduced to
3 1/2” W.C. by the pressure regulator
in the gas valve.
Propane Gas Operation
Inlet pressure to the gas valve must
be 11”W.C. When properly converted
to Propane gas, the pressure is regulated at 10” W.C.
SAFETY INFORMATION
For your safety read before lighting.
A. The first lighting of the furnace af-
ter any home setup must be performed by a qualified service
technician.
B. If this appliance has a pilot that
must be lit by hand, follow these
instructions exactly.
C. BEFORE LIGHTING smell all
around the furnace for gas. Be
sure to smell next to the floor because some gas is heavier than
air and will settle on the floor.
WHAT TO DO IF YOU SMELL GAS:
D Donottrytolightanyappliance.
D Do not touch any electric switch
and do not use any phone in your
building.
D Immediately call your gas suppli-
er from a neighbor’s phone. Follow the gas supplier’s instructions. If you cannot reach your
gas supplier, call the fire department.
D. Use only your hand to push in the
gas control lever. Never use
tools. If the lever will not push in
by hand, don’t try to repair it. Call
a qualified service technician.
Force or attemptedrepairmay result in a fire or explosion.
E. Do not use this furnace if any part
has been under water. Immediately call a qualified service technician to inspect the furnace and
to replace any part of the control
system and any gas control
which has been under water.
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Unitary Products Group

INSTRUCTIONS FOR DGPT STANDING PILOT MODELS
LIGHTING INSTRUCTIONS
1. STOP! Read the SAFETY INĆ
FORMATION.
2. Set the thermostat to the lowest
setting.
3. Turn off all electrical power to the
appliance.
4. Remove the furnace doors.
5. Push in the gas control lever
slightly and move right to “OFF”.
DO NOT FORCE.
6. Wait ten (10) minutes to clear out
any gas. Then smell for gas, including near the floor. If you smell
gas, STOP! Follow “C” in the
SAFETY INFORMATION. If you
don’t smell gas, go to the next
step.
7. Open hinged observation door,
the pilot is foundat the end of the
pilot shield on the left side of the
burner.
8. Slightly depress the gas control
lever and move it to the left to the
“ON” position and release; then
move it to the “PILOT” position.
9. Move the control lever to “SET”
and hold. I mmediately light the pilot with a match (use match holder provided). Continue to hold the
control lever for about one (1)
minuteafterthepilotislit.Release the lever and it will spring
back to the “PILOT””position. Pilot should remain lit. If it goes out,
repeat steps “5” through “9”
above.
D If the lever does not spring back
when released, stopand immediately call your service technician
or gas supplier.
D If the pilot will not stay lit after sev-
eral tries, move the gas controllever to “OFF” andcall your service
technician or gas supplier.
10. Move the gas control lever to
“ON”.
11. Replace the furnace doors.
12. Turn on all electric power to the
furnace. Set the thermostat to
“HEAT” and/or the desired temperature setting. Set the ON-OFF--FAN switch to “ON”.
In the event of any flashback or exĆ
plosion, immediately shut off the
furnace and call your servicetechĆ
nician.
To Turn off Gas to A ppl i ance
1. Set the thermostat to the lowest
setting.
2. Turn off all electric power to the
appliance if service is to be performed.
3. Remove the furnace doors.
4. Move gas control switch to “OFF”
position. DO NOT FOR CE.
5. Replace the furnace doors.
GAS CONTR OLCONTROL LEVER
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PRESSURE REGULATING DEVICE
FIGURE 1 -- ROBERT SHAW
GAS VALVE
SEQUENCE OF OPERATION
1. On a call for heat, the thermostat
contacts close, supplying 24 VAC
to the gas valve.
2. Whenthegasvalveisenergized
it steps open at a reduced flow
and opens f ully after approximately 10 seconds.
3. When the call for heat is satisfied
the thermostat contacts open,
thegasvalveshutoffgasflow.
THE FURNACE CONTROL S
AND THEIR FUNCTION
1. “ON--OFF --FAN” switch turns
electrical power to the furnace on
and off. The switch must be set in
the “ON” position for the furnace
to operate. To run the blowercontinuously without heating, set the
swi t ch to “FAN”.
2. Limit Control -- This furnace is
protected by two (2) high temperature limit switches. The lower
limitswitchisanautomaticreset
type.
The upper limit switch near left
side of blower is a manual reset
type limit switch (See Figure 2).
If burner does not function, turn
system switch to OFF and push
reset button in center of limit
switch.
Chute to left of blower is hot. Use
care when resetting limit switch
to avoid burns to hand and arm.
If the upper limit switch trips
again soon after resetting, turn
the furnace System Switch to
the OFF position and call your
nearest authorized service techĆ
nician.
UPPER LIMIT
SWITCH
(MANUAL
RESET)
BLOWER
SYSTEM
SWITCH
AUTOMATIC
RESET LOWER
LIMIT SWITCH
HOTHOT
FIGURE 2 -- FURNACE CONTROLS
PILOT
ACCESS
DOOR
GAS VALVE
BURNER AIR
SHUTTER
ADJUSTMENT
ROD
3. Gas Valve -- The gas valve is
100% shut--off type and will fail
safe if for some reason the gas is
turned off or the pilot goes out. It
is also of the modulating or “step-open” type which means they
open to a “low fire” position and
after a few seconds “step--open”
to “high fire”.
Unitary Products Group
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