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340, 340X

Automatic Reseating Temperature and Pressure Relief Valves


1 1/2 in. (38mm)


Series 340, 340X Automatic Reseating Temperature and Pressure Relief Valves are used in commercial water heater applications to provide automatic temperature and pressure protection to hot water supply tanks and hot water heaters. They feature a bronze body with NPT male inlet and NPT female outlet connections, stainless steel spring and thermostat tube, tamper-resistant bonnet screws, automatic reseating feature, and test lever. Model 340 has a 3 in. (80mm) thermostat. Model 340X has an 8 in. (200mm) thermostat. Series 340, 340X are ASME rated and CSA listed. Temperature Relief: 210°F (99°C), Pressure Relief Range: 75 to 150psi (5.2 to 10.3 bar), Standard Pressure Settings: 75, 100, 125, or 150psi (5.27, 7.03, 8.79, or 10.55 bar).

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Disclaimer: Watts product dimensions in U.S. customary units and metric are approximate and are provided for reference only. For precise measurements, please contact Watts Technical Service. Watts reserves the right to change or modify product design, construction, specifications, or materials without prior notice and without incurring any obligation to make such changes and modifications on Watts products previously or subsequently sold.

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Additional Information

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