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I have a Chiller system that has a load side water flow of 270gpm. The PVC piping is 4". The Spears brand Y strainer is also 4" PVC,but the strainer is only rated at 168gpm.The circ's pressurers  are 22psig in and 43psi out.The strainer screen had been removed years ago.If the screen was in place what would some of the issues be? Cavitation? Damage to the strainer body?Noise? Reduced water flow ? Would the water velocity increase thru the strainer? Would the strainer be ripped apart and  the debris sent out into the water circuit.?Would the circ's impeller be damaged by any cavitation caused by the strainer? The strainer is on the return side of the circ.Would the circ's pressure be affected? I am concidering upsizing the strainers to 6".


  • Eugene Silberstein_2
    Eugene Silberstein_2 Member Posts: 349
    I would assume....

    Based on what you have posted, I am willing to wager that there was indeed a previous water flow problem (probably as the strainer clogged up) that caused an earlier technician to remove the screen in the first place. Strainers are rated for a clean-screen flow rate, which will obviously be well above the actual flow rate once the screen starts doing its job.

    I would agree with your decision to put in a larger (6") strainer, as this will have no negative effect on the system, will clog much slower than the 4", and not provide a significant restriction to water flow.

    With the 4" strainer intact, there was very likely cavitation and noise, but the most common problem was likely that of high pressure issues.

    Keep us posted!
  • Techman
    Techman Member Posts: 2,144

    Thank you professor, I spoke w/people from Legend Valve Co, Spears Valve Co and Sure Flow Equipment and it seems  the existing  Y strainer are indeed sized improperly . It also seems to be that a Basket strainer would be much better suited for this application . The proper size is being figured out now,so I'll wait until more knowledgable brains point me in the right direction.  Very interesting indeed ! This profession is one 'ell of a challenge, and I love it!!!!!!!!!!!!!!!!!!!!!!!!1
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