Lochinvar 51-211 operation manual Check inlet gas supply, Natural Gas Pipe Capacity Chart

Installation & Operation Manual

7 Gas connections

Table 7A Natural Gas Pipe Size Chart

Nominal					Natural Gas Pipe Capacity Chart
Iron Pipe				Length of Pipe in Straight Feet for 1/2 PSI
Size (Inches)
	10	20	30	40	50	60	70	80	90	100	125	150	175	200
1/2	175	120	97	82	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
3/4	369	256	205	174	155	141	128	121	113	106	95	86	79	74
1	697	477	384	328	292	267	246	236	210	200	179	164	149	138
1-1/4	1400	974	789	677	595	543	502	472	441	410	369	333	308	287
1-1/2	2150	1500	1210	1020	923	830	769	707	666	636	564	513	472	441
2	4100	2820	2260	1950	1720	1560	1440	1330	1250	1180	1100	974	871	820
2-1/2	6460	4460	3610	3100	2720	2460	2310	2100	2000	1900	1700	1540	1400	1300
3	11200	7900	6400	5400	4870	4410	4000	3800	3540	3330	3000	2720	2500	2340
4	23500	16100	13100	11100	10000	9000	8300	7690	7380	6870	6150	5640	5130	4720

￿WARNING

Knight wall mount boilers are typically shipped ready to fire on natural gas. Check boiler rating plate to determine which fuel the boiler is set for. If set to natural gas, it may be converted to LP by installing an orifice (see page 13). In order to operate on LP gas, an orifice MUST BE installed. Failure to comply could result in severe personal injury, death, or substantial property damage.

Check inlet gas supply

NOTICE	CSA or UL listed flexible gas connections
	are acceptable, but you must exercise
	caution to ensure that the line has
	adequate capacity to allow your boiler
	to fire at full rate. Consult with local
	codes for proper installation or service
	procedures.

3.	Loosen the set screw one (1) full turn from inside the
	pressure tap on top of the gas valve. Place the tubing of
	the manometer over the tap once the set screw is
	loosened as shown in FIG. 7-3.
4.	Slowly turn on the gas supply at the field installed
	manual gas valve.

￿WARNING

DO NOT adjust gas valve outlet pressure. The gas valve is factory-set for the correct outlet pressure. This setting is suitable for natural gas and propane, requiring no field adjustment. Attempting to alter the gas valve outlet pressure could result in damage to the valve, causing potential severe personal injury, death, or substantial property damage.

5.	Turn the power switch to the “ON” position.
6.	Adjust the temperature set point on the control panel of
	the SMART SYSTEM control module to call for heat.
7.	Observe the gas supply pressure as the burner fires at
	100% of rated input. Percent of burner input will be
	displayed on the control panel.
8.	Ensure inlet pressure is within specified range.
	Minimum and maximum gas supply pressures are
	specified in this section of the manual.

The gas piping must be sized for the proper flow and length of pipe, to avoid excessive pressure drop. Both the gas meter and the gas regulator must be properly sized for the total gas load.

If you experience a pressure drop greater than 1 inch w.c., the meter, regulator, or gas line is undersized or in need of service. Perform the steps below when checking inlet gas supply:

1.Turn the main power switch to the “OFF” position.

2.Shut off gas supply at the manual gas valve in the gas piping to the appliance.

50

9.	If gas supply pressure is within normal range and no
	adjustments are needed, proceed on to Step 11.
10.	If the gas pressure is out of range, contact the gas utility,
	gas supplier, qualified installer or service agency to
	determine the necessary steps to provide proper gas
	pressure to the control.
11.	Turn the power switch to the “OFF” position.
12.	Shut off the gas supply at the manual gas valve in the gas
	piping to the appliance.
13.	Remove the manometer from the pressure tap on top of
	the gas valve. Re-tighten the set screw inside the pressure
	tap.