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Watts Series 174A, 374, 740 ASME Water Pressure Relief Valves

Watts
ASME Water Pressure Relief Valves
Series 174A, 374, 740

Series 174A
Bronze body safety relief valves for pressure protection only of all types of hot water heating boiler equipment. Pressure range 30 to 150psi (2 - 10 bar) with corresponding high ratings from 650,000 to 14,370,000 BTU/hr. Female inlet and outlet co nnect ions. Size s 3⁄4” - 2” (20 - 50mm).

Series 374A
Iron body with forged bronze inlet, 550,000 BTU/hr rating. 3⁄4” (20mm) only.

Series 740
Iron body with expanded outlets for hot water space heating boilers. Pressure range 30 to 75psi (2 to 5 bar) with orresponding high ratings from 925,000 to 10,700,000 BTU/hr.

Series 174A
Bronze body safety relief valves for pressure protection
only of all types of hot water heating boiler equipment.
Pressure range 30 to 150psi (2 - 10 bar) with
corresponding high ratings from 650,000 to 14,370,000
BTU/hr. Female inlet and outlet co nnect ions. Size s 3⁄4” -
2” (20 - 50mm).
Series 374A
Iron body with forged bronze inlet, 550,000 BTU/hr rating.
3⁄4” (20mm) only.
Series 740
Iron body with expanded outlets for hot water space
heating boilers. Pressure range 30 to 75psi (2 to 5 bar)
with orresponding high ratings from 925,000 to 10,700,00

• Seat located above drain; water can’t be trapped and sediment can’t foul seat.
• Non-mechanical seat-to-disc alignment will not stick or freeze.
• Water seal of high temperature resisting material isolates spring working parts from water during relief.

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Cat #Size (Dn) in.Size (Dn)mmModel:Height in.Height mmLength in.Length mmWeight lbs.Weight kg.TypeApplication:
374A3⁄4 x 3⁄420 x 2035⁄89221⁄2641.13.5SERIES 174A
174A3⁄4 x 3⁄420 x 20M351⁄813021⁄2641.50.7SERIES 174A
174A1 x 125 x 25M153⁄41463763.131.4SERIES 174A
174A11⁄4 x 11⁄432 x 32M183⁄821343⁄41216.252.8SERIES 174A
174A11⁄2 x 11⁄240 x 40M922947⁄81247.253.3SERIES 174A
174A2 x 250 x 50M115⁄829561⁄415913.756.2SERIES 174A
7403⁄4 x 120 x 25M155⁄81433761.889SERIES 740
7401 x 11⁄425 x 32M71⁄418431⁄2893.131.4SERIES 740
74011⁄4 x 11⁄232 x 40M83⁄422245⁄81176.132.8SERIES 740
74011⁄2 x 240 x 50M91⁄423551⁄41337.503.4SERIES 740
7402 x 21⁄250 x 65M115⁄829563⁄417116.507.5SERIES 740