GSI Outdoors PNEG-377 Self-Operatedmodulating Valves, Fan and Heater, Bypass Orifice Selection

SELF-OPERATED MODULATING VALVES

Fan and Heater

Installation and Operation Instructions, continued

Be sure the valve is installed so the gas flows through the body in the proper direction as indi- cated by the arrow on the body.

On direct or indirect fired vaporizer systems in which hot LP gas is flowing through the valve, install the valve with the bellows pointing down. This allows the temperature sensing element to perform properly. In vapor withdrawal systems, the gas flowing through the valve is cooler than the sensing bulb and valve is cooler thatn the sensing bulb and valve mounting position is not as important.

The temperature sensing bulb should be installed so the capillary end of the bulb is always higher than the plugged and of the bulb (see figure 3.)

If the installation requires that the bulb be in a horizontal position, it is very importanat to be sure that the word "TOP" appears at the top or upper- most surface of the bulb. (see Figure 4).

CAUTION: Do not kink or sharply bend the capillary tubing. Coil and secure excess capillary if installed where subjectd to vibration, allowing some slack in capillary to avoid "violin string" vibrations. Do not allow capillary to rub surfaces where friction can damage the tubing.

Figure 3-Capillary-end of bulb higher than plugged-end of temperature bulb.

Figure 4-Horizontal bulb mounting with "TOP" at top or uppermost surface of bulb.

Bypass Orifice Selection

These valves have a threaded hole in the internal web of the valve for an internal bypass. ( See figure 5) They are normally supplied with a solid plug installed in this hole for complete shutoff. Five drilled orifice fittings are supplied with each valve for field installation, if bypass is needed. The bypass orifice is ued to maintain a minimum flame which will burn even when the close-off point has been reached. When bypass is required, remove the solid plug and replace with the proper orifice plug. See selection table.

Figure 5-Cutaway view showing location of orifice plug

Figure 6-Typical piping for the V50 Valve

Orifice Sizes in Kit

Number PLG14A-600R

	Orifice Size		Color
	In.	mm	Code
.040		1.02	Red
	.062	1.57	Yellow
	.078	1.98	Green
	.093	2.36	Blue
	.125	3.18	Aluminum
	Solid Plug		Brass

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