Goodman GMVM Service Instructions Manual page 44

OPERATION
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 vaporization, rec-
ommended regulator settings, and pipe sizing is available from
most regulator manufacturers and propane gas suppliers.
Since propane gas will quickly dissolve white lead and most stan-
dard commercial compounds, special pipe dope must be used.
Shellac-based compounds resistant to the actions of liquefied
petroleum gases such as Gasolac®, Stalactic®, Clyde's® or
John Crane® are satisfactory.
Refer to the following illustration for typical propane gas installa-
tions and piping.
First Stage
Regulator
200 PSIG
Maximum
Propane Gas Installation (Typ.)
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
Tubing Tubing Size, O.D. Type L
Length
Feet 3/8" 1/2"
10 730 1,700
20 500 1,100
30 400 920
40 370 850
50 330 770
60 300 700
80 260 610
100 220 540
125 200 490
150 190 430
175 170 400
200 160 380
To convert to capacities at 15 psig settings - multiply by 1.130
To convert to capacities at 5 psig settings - multiply by 0.879
Propane Gas Piping Chart I
44
5 to 15 PSIG
(20 PSIG Max.)
Continuous
11" W.C.
Second Stage
Regulator
Nominal Pipe Size
Schedule 40
5/8" 3/4" 7/8" 1/2"
3,200 5,300 8,300 3,200
220 3,700 5,800 2,200
2,000 2,900 4,700 1,800
1,700 2,700 4,100 1,600
1,500 2,400 3,700 1,500
1,300 2,200 3,300 1,300
1,200 1,900 2,900 1,200
1,000 1,700 2,600 1,000
900 1,400 2,300 900
830 1,300 2,100 830
780 1,200 1,900 770
730 1,100 1,800 720
Sizing Between Second or Second Stage Regulator & 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
Tubing
Length
Feet 3/8"
10 39
20 26
30 21
40 19
50 18
60 16
80 13
100 11
125 10
150 9
200 8
250 8
*Data in accordance with NFPA pamphlet No. 54
Circulating Air & Filters
D - A
UCT WORK IR
N
EVER ALLOW THE PRODUCTS OF COMBUSTION
,
MONOXIDE TO ENTER THE RETURN DUCT WORK OR CIRCULATION AIR
.
SUPPLY
Duct systems and register sizes must be properly designed for
the CFM and external static pressure rating of the furnace. De-
sign the ductwork in accordance with the recommended meth-
ods of "Air Conditioning Contractors of America" Manual D.
Install the duct system in accordance with Standards of the Na-
tional Board of Fire Underwriters for the Installation of Air Condi-
tioning, 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 at-
tached to the back of the furnace. For upflow installations requir-
ing 1800 CFM or more, use either two side returns or bottom
3/4"
return or a combination of side /bottom. Flexible joints may be
7,500
4,200
used for supply and return connections to reduce noise transmis-
4,000
sion. To prevent the blower from interfering with combustion air or
3,700
3,400
draft when a central return is used, a connecting duct must be
3,100
installed between the unit and the utility room wall. Never use a
2,600
2,300
room, closet, or alcove as a return air chamber.
2,100
1,900
C D
HECKING UCT
1,700
1,500
Refer to your furnace rating plate for the maximum ESP (ex-
ternal duct static) rating.
Total external static refers to everything external to the fur-
nace cabinet. Cooling coils, filters, ducts, grilles, registers
must all be considered when reading your total external static
pressure. The supply duct pressure must be read between
the furnace and the cooling coil. This reading is usually taken
by removing the "A" shaped block off plate from the end on
the coil; drilling a test hole in it and reinstalling the block off
plate. Take a duct static reading at the test hole. Tape up the
test hole after your test is complete. The negative pressure
must be read between the filter and the furnace blower.
Tubing Size, O.D. Type L
1/2" 5/8" 3/4" 7/8" 1/2" 3/4"
92 199 329 501 275 567
62 131 216 346 189 393
50 107 181 277 152 315
41 90 145 233 129 267
37 79 131 198 114 237
35 72 1,211 187 103 217
29 62 104 155 89 185
26 55 90 138 78 162
24 48 81 122 69 146
21 43 72 109 63 132
19 39 66 100 54 112
17 36 60 93 48 100
Propane Gas Piping Chart II
F
LOW
WARNING
,
S
TATIC
Nominal Pipe Size
Schedule 40
1" 1-1/4" 1-1/2"
1,071 2,205 3,307
732 1,496 2,299
590 1,212 1,858
504 1,039 1,559
448 913 1,417
409 834 1,275
346 724 1,066
307 630 976
275 567 866
252 511 787
209 439 665
185 390 590
INCLUDING CARBON