Suburban NT.12SE Guide

USER'S INFORMATION
MANUAL
For Models
NT.12SE . NT.16SE . NT.2OSE
This book contains instructions for operating and
maintaining the furnace. Keep with unit at all times.
Should you require further information, contact your
dealer or nearest Suburban Service Center.
WARNING! lnstallation of this appliance
must be made in accordance with the
written instructions provided in this
manual. No agent, representative or
employee of Suburban or other person
has the authority to change, modify or
waive any provision of the instructions
contained in this manual.
WARNING! Be sure the furnace and all
ignition systems are "OFF" during any
type of refueling and while vehicle is in
motion or being towed.
WARNING! lmproper installation,
adjustment, alteration, service or
maintenance can cause property damage,
personal injury or loss of life. Refer to the
installation instructions and/or owners
manual provided with this appliance.
SUBURBAN MANUFACTURING COMPANY
Post Office Box 399
Dayton, Tennessee 37321
Due to high temperatures, the unit should be located out of traffic and
away from furniture and draperies.
Ghildren and adults should be alerted to the hazards of high surface
temperatures and should stay away to avoid burns or clothing ignition.
Young children should be carefully supervised when they are in the same
room as the unit.
Clothing or other flammable material should not be placed on or near the
unit.
Any safety screen or guard removed for servicing the unit must be
replaced prior to operating the unit.
The area around the unit must be kept clear from combustible materials,
gasoline and other Ilammable vapors and liquids.
lnstallation and repairs should be done by a qualified service person.
The unit should be inspected before use and at least annually by a
qualified service person. More frequent cleaning may be required due to
excessive lint from carpeting, bedding material, etc. lt is imperative that
control compartments, burners, and circulating air passageways of the
unit be kept clean.
Suburban
Manufacturing Company
a subsidiary or AIRXCEL' lnc.
\-.
\-
WARNING: lf the information in this
manual is not followed exactly, a fire or
explosion may result causing property
damage, 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
. Extinguish any open flame.
. Evacuate all persons from the vehicle.
. Shut off the gas supply at the gas
container or source.
. Do not touch any electrical switch, or
use any phone or radio in the vehicle.
. Do not start the vehicle's engine or
electric generator.
. Gontact the nearest gas supplier or
qualified service technician for repairs.
. lf you cannot reach a gas supplier or
qualified service technician, contact the
nearest fi re department.
. Do not turn on the gas supply until
the gas leak(s) has been repaired.
- lnstallation and service must be
performed by a qualified installer,
service agency or the gas supplier.
Form No.2465-C

MAINTENANCE AND CLEANING
and/or the production of carbon mr'r:lxide exists ri!:,lh can cause
hare^n.l iniirrv nronerlv demaoe or lgss of life.
!-ARNING! It the :er rl ll I applianc; iails io maintain it in ihe
condition in which it was shipped irom the lactory or it the appliance is
not usia sotety tor its intenddd purpose or if appliance is.not maintained
in accordancswith the instructiona in thi! "nanual, thcn the risk of a fire
CAUTION: Label all wires belore disconnecting for servicing' Proper
oolaritv must be observed so the furnace molor will run with the proper
Eiri"ri6n of rotation to insure correct air delivery. (See wiring diagram)'
CAUTION: Label all wires prior to disconnection when servicing.controls'
Wiring erro, can cause improper and dangerous lurnace operation'
Always verily proper operation ot turnace after servicing'
Your lurnace should be inspected by a qualitied service agency yearly
riJror6irriiing rhe lurnace oir. Partictilar attention should be given to the
tollowing items.
1 . lnsoect furnace installation and vent termination lo be sure Iurnace is properly
ii,.iiiio li.,, pir6J (SLe lnstallation lnstructions)' that vent terminates to lhe
ii,iorpt"i.fino'inat vent tubes overlap properly (See Installing Vent
Assembly).
2. lnsDect chamber and venting to assure that these components are physically
siu.Ol *,tnort nolei or exceJsive corrosion and that the installation and/or
ie-iniiif f aiion is in accordance with Suburban's lnstallation lnstructions.
(Reference installation manual supplied with furnace.)
WARNING! lt is imperative that the products ol combustion be properly
vented to atmosptiere and that all combustion air supplied to burner be
drawn trom outside atmosPhere'
3. Check the base on which furnace is mounted. Be sure it is physically sound'
void of any sagging, deterioration, etc.
4. lnsoect furnace, the venting and the gas piping to furnace for obvious signs
of det6rioration. Correct any defects at once
5- lnsDect combustion chamber lor restrictions in exhaust or intake ll is
irojiStiue that the flow of intake combustion air and the flow of exhaust gases
u"Ino "ioltt"a to the outside atmosphere not be obstructed Any soot or loose
debr"is should be blown out using compressed air.
6. lnsoect all qaskets. lf any gaskets show signs ol leakage or deterioration,
idptaiE tt L.. Biie operation o-f the furnace depends on all gaskets being tight'
7. lnspect return air inlet openings to the furnace. Bemove any restrictions to
assure adequate air flow.
You, as the owner/user, should inspect the furnace monthly during the
heaiino season for oresence of soot oh vent. Operating the furnace under this
lJnJiii6n corto ieid'io serious property damage. persohal iniury or loss ot life
itiooi is ouser"d on the vent, imriedihtely shut the furnace down and contact
a qualified service agencY.
Listedbelowareseveralsafetyrelateditemsthatyoushouldfol|owduringthe
heating season to assure continued safe operation ol the furnace'
1 . lnsDect furnace venting. Venting must be free of obstructions, void of soot and
propeily terminated to the atmosphere.
WARNING! Do not install screens over the vent lor any reason' Screens
*iri riliorei""tricted and cause unsafe furnace operation' Accessories
marketed tor RV products which we do not recommend. For
v. onlv factory authorized parts are to be used on your tqnace'
afe
2. Periodically observe the main burner flame to assure it is burning with a hard
blue flame with well defined burner ports (See Figure 2). lf flame appears yellow
or burner has a lazy flame, shut furnace down. lt is possible that burner needs
cleaning or replaced. To inspect the ntain burner, remove the four (4) screws-(A,
B, C and D) s'ecuring the burner access door to the combustion chamber (See
Figure 1). li excessi-ve rust and corrosion are present on burner surface, the
bu-rner must be thoroughly cleaned or replaced. The burner may be cleaned
using a steel wire brusl-iand blown clean using high compression air. Contact a
qualifled service person for assislance.
NOTE: To observe flame, cabinet fronl must be removed. Operation o{ burner
can then be€bserved through the viewing window on front of chamber. (See
Figure 1.)
3. Periodically inspect the vent for obstructions or presence ol soot. Soot is
formed when6ver iombustion is incomplete. This is your visual warning that the
furnace is operating in an unsale manner. l{ soot is present, immediately shut
Iurnace down and contact your dealer or a qualilied service person
4. Keep furnace clean. More frequent cleaning may be required due to excessive
lint from carpeting. bedding material, eta. lt is imperative that control
compartments, buriers and ciiculating air passageways of the appliance be kept
clean.
5. The motor is permanently lubricated and requires no oiling
6. Keep the furnace area clear of any combustible materials, gasoline or other
llammable vapor and liquids.
7. Before operating furnace, check the location of the lurnace vent to make sure
it will not be bloclied by the opening of any door on the trailer. lf it can be
blocked, do not operate the lurnace with the door open.
8. Do not restrict the flow of combustion air or the warm air circulation 10 the
furnace. To do so could cause personal injury and/or death.
9. Never ooerate the furnace if you smell gas. Do not assume that the smell of
oas in your RV is normal. Any ttme you detect the odor of gas. it is to be
donsidered life threatening and corrected immediately. Extinguish any open
tlames including cigarettes and evacuate all persons from the vehicle. Shut off
gas supply at LF gas bottle. (See safety notice on front cover of this manual )
10. lmmediately shut furnace down and call a service agency i, furnace cycles
erratically or delays on ignition.
WARNING! Should overheating occur, or the gas supply fail to shut off,
shut ofl the manual gas valve to the appliance before shutting oft the
electrical
11. Never attempt to repair damaged parts. Always have them replaced by a
qualif ied service agency.
12. Never attempt to repair the furnace yourself. Seek the help ol a qualilied
service person.
13. Clothing or other flammable material should not be placed on or near the
appliance.
14. Always follow the Operating Instructions. Do not deviate from the step-by-
step procedures.
1 5. ln any installation in which the vent ol this appliance can be covered due to
the consiruction o, the R',/ or some special feature of the RV such as slide out,
ooo-uo etc. alwavs insu'e that the apoliance cannot be operated by setting the
indrmbstat to thd positive'OFF'poiiiion and shutting off all electrrcal and gas
supply to the appliance. Never operate furnace with vent covered.
16. When considering add-on rooms, porch or patio, attention must be given to
the venting of your luinace. For your safety, do not terminate furnace vent inside
add-on ro6ms, screen porch oionto patibs. Doing so will result in products of
combustion being vented into the room or occupred areas.
HIGH YELLDV
BLUE FLAME
BURNER
CIRRECT INCT]RRECT
FLAME FLAME
Figure 2
2
CEI.,IBUSTION CHAMBER
BURNTR DBSERVATI!N
V]NDOV CABINTT
ELECTRDDE VALVE
GAS T]TTING
BURNER ACCESS DEDR SPARK V]RE
Figure 1

OPERATI NG INSTRUCTIONS
WARNING: Do not operate furnace while vehicle is in motion
or beino towed.
NOTE: During initial firing of this furnace a burn-off of excess paint
and oils remaining from manufacturing process may cause
"smoking" for 5 - '10 minutes.
FOR YOUR SAFEW READ BEFORE OPERATING
- -
ARNING: lf you do not follow these instructions exactly, a fire
or explosion may result causing property damage, personal injury
or loss of life.
A" This appliance does not have a pilot. lt is equipped with an ignition device
which automatically lights the burner. Do not light the burner by hand.
B. BEFORE OPERATING smell all around the appliance area 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
. Extinguish any open flame.
. Evacuate all persons from lhe vehicle.
. Shut off the gas supply at the gas container or source.
. Do not touch any electric switch or use any phone or radio in the vehicle.
. Do not start the vehicle's engine or electric generator.
. Contact the nearest gas supplier or qualified service technician for repairs.
. lf you cannot reach a gas supplier or qualified service technician, contact
the nearest flre department.
. Do nct turn on the gas supply until the gas leak(s) has been repaired.
C. Use only your hand lo turn the handle cn the manual shut offvalve. Never use
tools. lf the handle will not turn by hand, don't try to repair it, call a qualified
service technician. Force or attempted repair may result in a fire or explosion.
D. Do not use this appfiance if any part has been under water. lmmediately call
aqualified service technician to inspect the appliance and to replace any part
of the control system and any gas control which has been under watei. '
OPERATING INSTRUCTIONS
\-"
1. STOP! Read the safety information above on this label.
2. Set the thermostat to lowest setting.
3. Turn off all electric power to the appliance.
4. The appliance is equipped with an ignition device which automatically lights
the burner. Do not try to light the burner by hand.
5. Turn shut-off valve to "OFF". This furnace is equipped wrth a valve shut-off
switch. With switch in "OFF" position, gas will not flow to burner nor will the
furnace operate.
6. Wait flve (5) minutes to clear out any gas. Then smell for gas including near
the floor. lf you then smell gas, STOP! Follow "B" in the safety information
above on this label. lf you don't smell gas, go to next step.
7. Turn on all electric power to the appliance. These units are for use with LP
gas only. LP gas is heavier then air. Therefore, to better clear out any gas,
the heater should be operated for five (5) minutes with the blower on and the
gas off.
8. Turn shut-off valve to "ON".
9. Set thermostat to desired setting.
10. lf the appliance will not operate, follow the instructions "To Turn Off Gas to
Appliance" and call your service technician or gas supplier. NOTE: lf the
furnace should lock-out, the blower will go off in 5 minutes and remain off
until unit is reset by reactivating thermostat.
TO TURN OFF GAS TO APPLIANCE
1. Set the thermostat to lowest setting, then move lever to "OFF" position. 3. Turn shut-off valve to "OFF". Do not force.
2. Turn off all electric power to the appliance if service is to be performed.

v,
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2
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35
37i
39\l
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1B
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40.
Figure 3
43
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3
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Figure 4

Figure 5
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REPLACEMENT PARTS LIST
Models
NT.12SE . NT-16SE . NT-2OSE
Only factory authorized parts are to be used. Do not attempt to repair defective parts.
When ordering repair parts from your dealer, a Suburban Service Center, or distributor,
always give the following information.
1. Part Number (Not ltem No.)
2. Part Description
3. Model No., Serial No. and Date Code of Furnace
4. Number of Parts Required
Y.,
Item
No.
1
2
4
5
6
7
I
o
10
10A
11
1'1A
12
14
17
1B
19
20
21
214
22
24
28
29
30
31
34
35
36
38
40
41
42
43
44
45
46
47
48
50
5'r
54
56
57
58
59
60
61
62
63
64
65
Part Number
NT.12SE NT.16SE NT.2OSE
161154 161154 16115/
121224 121224 121224
121520 121520 121520
030785P8 030785P8 030785P8
030785SG
030785GL
101887 '101887 10',1887
070569 070569 070569
050712 050712 050712
05071 1 05071 1 05071 1
050708 050708 050708
260098 260098 260098
121853 121853 121853
062476 062476 062476
121247 121247 121247
230933 230933 230933
121364 121364 12',t3M
120672 120672 120672
0208848K 0208848K 0208848K
1213AA 121388 121388
120158 120158 120158
070243 070243 070243
230635 230635 230849
120158 120158 120158
120714 120714 120714
230714 230714 230714
120158 120158 1201s8
120158 120158 120158
070270 070270 070270
121357 121357 121357
520820 520820 520820
062392 062392 062392
120158 120158 120158
070450 070450 070450
120717 120717 120717
120153 120158 120158
350082 350082 3s0082
't20158 120158 120158
3902228K 3902228K 3902228K
12',t329 121329 121329
070446 070446 070446
120722 120722 120722
3902238K 3902238K 390223BK
530089 530089 530089
070448 070448 070448
230616 230634 230634
350083 350083 350083
062290 062290 062290
121407 121407 121407
231931 231931 231S31
070163 070163 070163
121388 121388 121388
120717 120717 120717
030621 030621 030621
070398 070398 070398
170374 170374 170374
't61',t23 '161123 161123
062288 062288 062284
120158 120158 120158
170744 170744 170744
120615 120615 1206'15
180225 180224 180231
070449 070449 070449
010614 010614 010614
063249 063249 063249
232351 232351 232351
12015A 120158 '120158
Description
Thermostat (Suburban supplied themstat not
appli€ble to some models)
Screw, #1 0 x 3i4 (2 Required)
Screw, #8 x 3/8 (2 Required)
Cabinet Front (BroM)
Cabinet Front (Gray)
Cabinet Front (Light Gray)
Cabinet
Bushing
Tube, lntake (Standard) (5'Long)
Tube, lntake (Special) (2 3/4' Long)
Tube, lntake (Special) (7 3/4" Long)
Vent Cap and Exhaust Tube Asembly
Screw, #10 x 3i4 (6 Required)
Bracket, Microswitch Mounting
Screw, #2 - 56 x 5/8 (2 Required)
Microswitch Assembly
Washer Lock #2 (2 Required)
Nut, Hex #2-56 (2 Required)
Combustion Chamber/Shield Assembly
Screw, #10 x'112 With Serated Head (2 Required)
Screw, #8 x 3/8 (2 Required)
Grcmmet
Limit Switch
Screw, rlS x 3/8 (2 Required)
Screw, #6 x 1/4 (2 Required)
Splicer
Screw, #8 x 3i8 (2 Required)
Screw, #8 x 3/8 (2 Required)
Bushing
Screw, #6 x 5/8 (2 Required)
Module Board
Stiffener Bracket. Combustion Air Housing
Screw, #8 x 3/8 (2 Required)
Gasket, Bumer Tunnel
Nut '10-24 Hex Lock (2 Required)
Screw, #8 x 3/8 (2 Required;
Wheel, Combustion Air
Screw, #8 x 3/8 (9 Required)
Box, Combustion Air (Outside) Assembly
Nut 10-32 Hex Lock (2 Required)
Gasket, Combustion Air Box
Washer, Flat (2 Required)
Box, Combustion Air (lnside) Assembly
Grommet (2 Required)
Gasket, N.4otor
Motor
lmpeller, Room Air
Bracket, CombJStion Air Housing Mounting
Screw, #8 - 32 Self Tapping (2 Required)
Electrode
Gasket, Electrode
Screw, #10 x 1/2 Serrated Head (4 Required)
Nut 10-24 Hex Lock (2 Required)
Door, Burner Access
Gasket, Burner Access Door
Gas Fitting
Valve
Bracket, Manifold N,lounting
Screw, #8 x 3/B (2 Required)
Manifold Assembly
Screw, #8 x 1/2 (4 Required)
Orifice, Main Burner
Gasket, Manifold
Burner Assembly
Bracket, Switch, Mounting
Switch, ON/OFF
Screw. #8 x 3/8
Y-/
6