23
P
ROPANE
G
AS
T
ANKS
AND
P
IPING
I
F
THE
GAS
FURNACE
IS
INSTALLED
IN
A
BASEMENT
,
AN
EXCAVATED
AREA
OR
CONFINED
SPACE
,
IT
IS
STRONGLY
RECOMMENDED
TO
CONTACT
A
PROPANE
SUPPLIER
TO
INSTALL
A
GAS
DETECTING
WARNING
DEVICE
IN
CASE
OF
A
GAS
LEAK
.
S
INCE
PROPANE
GAS
IS
HEAVIER
THAN
AIR
,
ANY
LEAKING
GAS
CAN
SETTLE
IN
ANY
LOW
AREAS
OR
CONFINED
SPACES
.
P
ROPANE
GAS
ODORANT
MAY
FADE
,
MAKING
THE
GAS
UNDETECTABLE
EXCEPT
WITH
A
WARNING
DEVICE
.
•
•
WARNING
A gas detecting warning system is the only reliable way to
detect a propane gas leak. Rust can reduce the level of odorant
in propane gas. Do not rely on your sense of smell. Contact a
local propane gas supplier about installing a gas detecting
warning system. If the presence of gas is suspected, follow
the instructions on Page 3 of this manual.
All propane gas equipment must conform to the safety stan-
dards of the National Board of Fire Underwriters, NBFU Manual
58.
For satisfactory operation, propane gas pressure must be 10
inch WC at the furnace manifold with all gas appliances in
operation. Maintaining proper gas pressure 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 between
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 vaporization, rec-
ommended regulator settings, and pipe sizing is available from
most regulator manufacturers and propane gas suppliers.
Use a pipe thread compound that is approved for natural gas
and LP Gas.
Refer to the following illustration for typical propane gas instal-
lations and piping.
200 PSIG
Maximum
5 to 15 PSIG
(20 PSIG Max.)
Continuous
11" W.C.
Second Stage
Regulator
First Stage
Regulator
Propane Gas Installation (Typ.)
P
ROPANE
G
AS
P
IPING
C
HARTS
3/8"
1/2"
5/8"
3/4"
7/8"
1/2"
3/4"
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
Sizing Betw een Firs t and Second Stage R egulator*
Maxim um Propane C apacities lis ted are bas e d on 2 ps ig pres s ure drop at 10 ps ig s etting.
C apacities in 1,000 BTU /hou r.
Nom inal P ipe S iz e
Sc hedule 40
Tubing S iz e, O.D. Ty pe L
Pipe or
Tubing
Length,
Feet
3/8"
1/2"
5/8"
3/4"
7/8"
1-1/8"
1/2"
3/4"
1"
1-1/4"
1-1/2"
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
910
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
Pipe or
Tubing
Length,
Feet
Nominal Pipe S iz e
Schedule 40
Tubing Size, O.D. Type L
Sizin g Be tw een Secon d Stag e an d Ap pliance Re gu la tor*
Maxim um Pro pan e Ca pacitie s lis te d are b as ed o n 2 ps ig pres s ure d ro p at 10 p s ig s ettin g.
Cap acities in 1,00 0 BTU /h ou r.
C
IRCULATING
A
IR
N
EVER
ALLOW
THE
PRODUCTS
OF
COMBUSTION
,
INCLUDING
CARBON
MONOXIDE
,
TO
ENTER
THE
RETURN
DUCT
WORK
OR
CIRCULATION
AIR
SUPPLY
.
WARNING
Duct systems and register sizes must be properly designed for
the CFM and external static pressure rating of the furnace.
Ductwork should be designed in accordance with the recom-
mended methods of “Air Conditioning Contractors of America”
Manual D.
A duct system must be installed in accordance with Standards
of the National Board of Fire Underwriters for the Installation of
Air Conditioning, Warm Air Heating and Ventilating Systems.
Pamphlets No. 90A and 90B.
A closed return duct system must be used, with the return duct
connected to the furnace.
NOTE:
Ductwork must never be
attached to the back of the furnace. For installations requiring
more than 1800 CFM, use a bottom return or two sided return.
Supply and return connections to the furnace may be made
with flexible joints to reduce noise transmission. To prevent the
blower from interfering with combustion air or draft when a cen-
tral return is used, a connecting duct must be installed be-
tween the unit and the utility room wall. A room, closet, or
alcove must not be used as a return air chamber.
When the furnace is used in connection with a cooling unit, the
furnace should be installed in parallel with or on the upstream
side of the cooling unit to avoid condensation in the heating
