Thermo Modular Valve Pressure Ratings

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SeanW

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Hello all,

I recently bought a pair of left/ right thermo valves to make a set of doubles. The valves have a sticker just below the orifice that say 3000psi working pressure, yet the back of the valve has 232 bar stamped in it and a 5000psi burst disk is installed. Could someone help me understand why there are 3 different pressure standards on the valve and whether or not these would be suitable for faber 3442 HP100s? Thanks!
 
My sticker came off somehow, so it's not an issue for me.
 
The 3000 psi on the sticker is the working pressure of the burst disk installed in the valve. Technically it should be swapped out to match the working pressure of the tank, 3442. The 232 bar is the rated pressure of the valve. The 5000 psi is the burst pressure of the burst disk, 5/3 x working pressure. If you swap the burst disk out it should be fine for your application. Technically the valve is rated slightly below the working pressure of your tanks. Thermo does make a Pro series valve that is rated to that pressure.
 
Hello all,

I recently bought a pair of left/ right thermo valves to make a set of doubles. The valves have a sticker just below the orifice that say 3000psi working pressure, yet the back of the valve has 232 bar stamped in it and a 5000psi burst disk is installed. Could someone help me understand why there are 3 different pressure standards on the valve and whether or not these would be suitable for faber 3442 HP100s? Thanks!

3000psi is the originally installed burst disc, should have been changed but AL80's and HP steels use the same burst discs. 232psi is a Euro nominal working pressure so don't worry about that.

Your HP100's should have a 5250psi test pressure and an AL80 has a 5000psi test pressure, the disc is supposed to burst around 90% of that, and in the world of a thin piece of metal, bursting at 4500 vs 4700psi is functionally the same so I wouldn't change them out. Technically you can get 5250 burst discs but leaving 5000's on them is fine.

Weirdly this is one of the more convenient things about AL80's and HP tanks vs LP tanks, only really applicable for the hydro guys and valve rebuilders but they have to recalibrate for the LP steels but not for 3al and HP steel. Useless facts
 
Thank you all for the information! This was helpful
 
http://cavediveflorida.com/Rum_House.htm

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