GAS Pipe Sizing

Section III. Installation	12

Table 2.

PIPE SIZING FOR GAS LINE CONNECTIONS

MAXIMUM EQUIVALENT PIPE LENGTH (Ft.)

Natural Gas at 1000 B.T.U. per Cubic Foot

	1/2”	3/4”	1”	1-1/4”	1-1/2”	2”	2-1/2”

MODEL	NAT	NAT	NAT	NAT	NAT	NAT	NAT

200	-	30’	125’	450’	-	-	-

250	-	20’	70’	250’	600’	-	-

300	-	10’	50’	200’	400’	-	-

400	-	-	20’	100’	200’	400’	-

“RESIDENTIAL” NATURAL GAS 2 STAGE REGULATION

In many Natural gas line installations, the gas supplier and/or installer may utilize a two stage regulation process where by at the streets main gas supply they will install the first stage gas regulator, which would be at a higher pressure. This higher pressure is usually set at 2 psi or 5 psi and can be for long distances and in a much smaller pipe size. Then within a short distance of the pool heater, generally around

24 inches, they will install a second regulator, which is the second stage. This second stage regulator would be set at the minimum operating pressure for the heater. For “Natural Gas Pentair Pool Heaters” the minimum is 7 inches W.C.

See “Gas Pressure Requirement Charts”

Stage One "High Pressure" Gas Pipe Sizing

2 PSI @ 1000 B.T.U. Per CU. FT.

MAXIMUM EQUIVALENT PIPE LENGTH

	Model	0 to 50 Ft.		50 to 100		Ft.	100 to 150 Ft.

200	through 300	1/2	in.	1/2	in.		1/2 in.

	400	3/4 in.		3/4 in.			3/4 in.

	5 PSI @ 1000 B.T.U. Per CU. FT.

200	through 400	1/2	in.	1/2	in.		1/2 in.

Table 3.

Stage Two "Low Pressure" Gas Pipe Sizing

Stage 2 set at 7 in. W.C.

MAXIMUM EQUIVALENT PIPE LENGTH

Model	0 to 10 Ft.	10 to 20 Ft.

200 through 300	3/4 in.	3/4 in.

400	3/4 in.	1 in.

Stage 2 set at 7 in. W.C.

200 through 400	3/4 in.	1 in.

Table 4.

P/N 472089

Rev. E 4-19-05