A.O. Smith BTPN, COF, COBT, BTP-140-140 warranty Water Line Connections, Relief Valve, GAS Piping

TABLE 2

CAPACITY OF PIPE - NATURAL GAS IN CUBIC FEET PER HOUR

Maximum Based Upon Pressure Drop of 0.3” w.c. and Specific Gravity

of 0.60 and Maximum Gas Pressure of .5 psig.

Pipe Length			Pipe Size - Inches (IPS)
In Feet	1	1 1/4	1 1/2	2	2 1/2	3	4
10	520	1050	1600	3050	4800	8500	17500
20	350	730	1100	2100	3300	5900	12000
30	285	590	890	1650	2700	4700	9700
40	245	500	760	1450	2300	4100	8300
50	215	440	670	1270	2000	3600	7400
60	195	400	610	1150	1850	3250	6800
70	180	370	560	1050	1700	3000	6200
80	170	350	530	990	1600	2800	5800
90	160	320	490	930	1500	2600	5400
100	150	305	460	870	1400	2500	5100
125	130	275	410	780	1250	2200	4500
150	120	250	380	710	1130	2000	4100
175	110	225	350	650	1050	1850	3800
200	100	210	320	610	980	1700	3500

NOTE: Use Multiplier at right for other specific gravities and pressure drops.

CORRECTION FACTORS

Specific Gravity				Pressure Drop
Other than 0.60				Other than 0.3
Specific			Multplier	Pressure	Multiplier
Gravity				Drop
0.50	1.10			0.1	0.577
0.60	1.00			0.2	0.815
0.70	0.926			0.3	1.00
0.80	0.867			0.4	1.16
0.90	0.817			0.6	1.42
1.00	0.775			0.8	1.64
Propane - Air				1.0	1.83
1.10		0.740		2.0	2.58
Propane				3.0	3.16
1.55			0.622	4.0	3.65
				6.0	4.47
				8.0	5.15

Where an existing chimney or vent is to be used, be sure that the chimney or vent has adequate capacity for the number and sizes of gas appliances being vented through it. Inspect the chimney or vent and remove all soot or other obstructions, which will retard free draft.

Vent piping making horizontal runs must have a minimum upward slope toward the chimney or vent of 1/4” per foot. Vent pipe length should be kept as short as possible. Be sure that the vent pipe does not extend beyond the inside wall of a chimney.

In venting systems, where a continuous or intermittent back (positive) draft is found to exist, the cause must be determined and corrected. In some cases, a special vent cap may be required.

WATER LINE CONNECTIONS

The water heater may be installed by itself, or with a separate storage tank, on both single and two-temperature systems. When used with a separate storage tank, the circulation may be either by gravity or by means of a circulating pump.

SYSTEM CONNECTIONS

The system installation must conform to these instructions and to the local code authority having jurisdiction. Good practice requires that all heavy piping be supported.

THERMOMETERS (Not supplied)

Thermometers should be obtained and field installed as shown in the installation diagrams.

Thermometers are installed in the system as a means of detecting the temperature of the outlet water.

RELIEF VALVE

This water heater has been provided with an ASME rated pressure and temperature relief valve.

In addition to the appliance relief valve, each remote storage tank, which may be used in conjunction with this appliance, shall also be installed with a properly sized, rated and approved temperature (ANSI) and pressure (ASME) relief valve(s).

WARNING

THE PURPOSE OF A RELIEF VALVE IS TO AVOID EXCESSIVE PRESSURE OR TEMPERATURE INTO THE STEAM RANGE, WHICH MAY CAUSE SCALDING AT FIXTURES, TANK EXPLOSIONS, SYSTEM OR HEATER DAMAGE. NO VALVE IS TO BE PLACED BETWEEN THE RELIEF VALVE AND THE TANK.

A DRAIN LINE MUST BE CONNECTED TO THE RELIEF VALVE TO DIRECT DISCHARGE TO A SAFE LOCATION TO AVOID SCALDING OR WATER DAMAGE. THIS LINE MUST NOT BE REDUCED FROM THE SIZE OF THE VALVE OUTLET AND MUST NOT CONTAIN VALVES, RESTRICTIONS NOR SHOULD IT BE LOCATED IN FREEZING AREAS. DO NOT THREAD OR CAP THE END OF THIS LINE. RESTRICTED OR BLOCKED DISCHARGE WILL DEFEAT THE PURPOSE OF THE VALVE AND IS UNSAFE. DISCHARGE LINE SHALL BE INSTALLED TO ALLOW COMPLETE DRAINAGE OF BOTH THE VALVE AND LINE.

Your local code authority may have other specific relief valve requirements.

GAS PIPING

Contact your local gas service company to ensure that adequate gas service is available and to review applicable installation codes for your area.

Size the main gas line in accordance with Table 3. The figures shown are for straight lengths of pipe at 0.3 in. w.c. pressure drop, which is considered normal for low-pressure systems. Note that fittings such as elbows and tees will add to the pipe pressure drop.

Equivalent lengths of standard pipe in feet for listed fittings (add below values to Table 3).

Install vent lines from main gas regulator and (if applicable) a diaphragm gas valve. Vent line should be run to the outside of the building, terminating clear of windows or fresh air intakes. Outside terminal of vent should have a screen to prevent insects from building nests in vent pipe. The vent should terminate in a manner, which will preclude the possibility of water, snow, dirt or other matter from entering the line.

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