Purging; Gas Pressure Regulation; Operation; To Operate The Heater - A.O. Smith BTI-80 Installation, Operation, Service, Maintenance, Limited Warranty

TABLE 4 - GAS SUPPLY LINE SIZES (IN INCHES)*
MAXIMUM CAPACITY OF PIPE IN
CUBIC FEET PER HOUR
LENGTH NORMAL IRON PIPE SIZES (INCHES)
IN INPUT IN THOUSANDS BTU/HR
FEET 1/2" 3/4" 1" 1 1/4" 1 1/2"
10 175 360 680 1400
20 120 250 485 950
30 97 200 375 770
40 82 170 320 660
50 73 151 285 580
60 66 138 260 530
70 61 125 240 490
80 57 118 220 460
90 53 110 205 430
100 50 103 195 400
125 44 93 175 360
150 40 84 160 325
175 37 77 145 300
200 35 72 135 280
LENGTH NORMAL IRON PIPE SIZES (INCHES)
IN INPUT IN KW
METERS 1/2" 3/4" 1" 1 1/4" 1 1/2"
3.0 51 105 199 410
6.1 35 73 142 278
9.1 28 59 110 225
12.2 24 50 94 193
15.2 21 44 83 170
18.3 19 40 76 155
21.3 18 37 70 143
24.4 17 35 64 135
27.4 16 32 60 126
30.5 15 30 57 117
38.1 13 27 51 105
45.7 12 25 47
53.3 11 23 42
61.0 10 21 40
BEFORE PLACING THE HEATER IN OPERATION, CHECK FOR GAS
LEAKAGE. Use soap and water solution or other material acceptable for
the purpose in locating the leaks.
FLAME OR OTHER SOURCES OF IGNITION FOR THIS PURPOSE.
FIGURE 5 - GAS PIPING AND DIRT LEG INSTALLATION
DISCONNECT THE HEATER AND ITS MANUAL GAS SHUTOFF VALVE
FROM THE GAS SUPPLY PIPING SYSTEM DURING ANY SUPPLY
PRESSURE TESTING EXCEEDING 1/2 PSIG (3.45 kPa). GAS SUPPLY LINE
MUST BE CAPPED WHEN DISCONNECTED FROM THE HEATER FOR TEST
PRESSURES OF 1/2 PSIG (3.45 Kpa) OR LESS. THE APPLIANCE NEED NOT
BE DISCONNECTED, BUT MUST BE ISOLATED FROM THE SUPPLY PRESSURE
TEST BY CLOSING THE MANUAL GAS SHUTOFF VALVE.
2" 2 1/2"
2100 3960 6300 11000 23000
1460 2750 4360 7700 15800
1180 2200 3520 6250 12800
990 1900 3000 5300 10900
900 1680 2650 4750
810 1520 2400 4300
750 1400 2250 3900
690 1300 2050 3700
650 1220 1950 3450
620 1150 1850 3250
550 1020 1650 2950
500 950 1500 2650
460 850 1370 2450
430 800 1280 2280
2" 2 1/2"
615 1160 1845 3221
428 805 1277 2255
346 644 1031 1830
290 556 878 1552
264 492 776 1391
237 445 703 1259
220 410 659 1142
202 381 600 1083
190 357 571 1010
182 337 542 952
161 299 483 864
95 146 278 439 776
88 135 249 401 717
82 126 234 375 688
DO NOT USE MATCHES, CANDLES,
Gas line purging is required with new piping or systems in which air has
entered.
3" 4"
PURGING SHOULD BE PERFORMED BY PERSONS EXPERIENCED IN THIS
TYPE GAS SERVICE. TO AVOID RISK OF FIRE OR EXPLOSION, PURGE
DISCHARGE MUST NOT ENTER CONFINED AREAS OR SPACES WHERE
IGNITION CAN OCCUR. THE AREA MUST BE WELL VENTILATED AND ALL
SOURCES OF IGNITION MUST BE INACTIVATED OR REMOVED.
9700
8800
GAS METER SIZE — NATURAL GASES ONLY
8100
7500
Be sure the gas meter has sufficient capacity to supply the full rated gas
7200
input of the water heater as well as the requirements of all other gas fired
6700
equipment supplied by the meter. If gas meter is too small, ask the gas
6000
company to install a larger meter having adequate capacity.
5500
5000
4600
The gas pressure regulator is built into the gas valve and is equipped to
operate on the gas specified on model and rating plate. The regulator is
3" 4"
factory adjusted to deliver gas to burner at correct water column pressure
6735
allowing for a nominal pressure drop through the controls.
4626
3748
The minimum gas supply pressure for input adjustment must not be less
3192
than 4.5" w.c. (1.12 kPa) for natural gas.
2840
2577
Do not subject the combination gas valve to inlet gas pressures of more
2372
than 14.0" W.C. (3.48 kPa) - natural gas. A service regulator is necessary
2196
if higher gas pressures are encountered.
2108
1962
Gas pressure specified in Table 5, refer to flow pressure taken at pressure
1757
tap of automatic gas valve while heater is operating.
1610
1464
TABLE 5 – MANIFOLD PRESSURE SETTING
1347
Model
Number
BTI-80
BTI-100
It is recommended that a qualified person perform the initial firing of the
heater. At this time the user should not hesitate to ask the individual any
questions which he may have in regard to the operation and maintenance
of the unit.
1. Close the heater drain valve (Figure 1) by turning handle clockwise
.
2. Open a nearby hot water faucet to permit the air in the system to
escape.
3. Fully open the cold water inlet pipe valve (Figure 1) allowing the heater
and piping to be filled.
4. Close the hot water faucet as water starts to flow.
5. The heater is ready to be operated.
DO NOT ATTEMPT TO OPERATE WATER HEATER WITH COLD
WATER INLET VALVE CLOSED.
NEVER OPERATE THE HEATER WITHOUT FIRST BEING CERTAIN IT
IS FILLED WITH WATER AND A TEMPERATURE AND PRESSURE
RELIEF VALVE IS INSTALLED IN THE RELIEF VALVE OPENING OF THE
HEATER.
9

PURGING

CAUTION
GAS PRESSURE REGULATOR
Type of
Gas Input
Natural 76,500 Btu/hr
22.4 KW/hr
Natural 90,000 Btu/hr
26.4 KW/hr

OPERATION

TO OPERATE THE HEATER

WARNING
Manifold
Pressure
3.5 in. W.C.
0.87 kPa
3.5 in. W.C.
0.87 kPa