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  1. Rputvin

    Turning houses into boats...???

    edit: just noticed OP was banned. oh well
  2. Rputvin

    Chilled Water Constant Flow Reverse-Return Bypass

    Your towers don't look setup correctly to me. It might just be the schematic representation missing some detail but this appears to be setup to flow (treated) domestic water into the basin, and then pump the basin overflow and drain connections to facility drains. The basins will hold water...
  3. Rputvin

    Suggestion - forum title change?

    What happens when "the actual science" ends up being misinformation? Or obfuscated enough by the interested parties to no longer bear any resemblance to real science? But it gets parroted and disseminated like the propaganda it is. And to question its validity is to be labeled a non-believer...
  4. Rputvin

    when will the madness end ?

    I decided to go look this up. It says abolish the NOAA, with many functions eliminated, sent to other agencies, privatized, or placed under control of states/territories. It specifically mentions the NWS as being less reliable than private sector alternatives, and it would be better served...
  5. Rputvin

    Pump lost some flow after testing

    I've witnessed similar performance variations on end-suction centrifugal pumps where there is some rubbing between the case and impeller. Either from binding during installation, or getting the shim stack wrong when building the pump. We'll see it during runoff testing, a duplex system (1+1...
  6. Rputvin

    Dead head pressure when the density is not water

    That looks like a pump-flo (software) curve. The sizer should have the ability to change the fluid properties to match your slurry, and then your selection and datasheet info will have information that relates directly to your application. Not that knocking the dust off that part of the brain...
  7. Rputvin

    Help me in pump sizing for cooling tower water circulation

    Each of those pieces of equipment should have a manufacturer rating for required heat removal, including flowrate and temperature requirements. You need to build up a system diagram, decide on a nominal flowrate based on the equipment requirements, and then match the pump head to the expected...
  8. Rputvin

    Automatic Balancing Valves in Chilled Water Header System

    I was going to suggest a similar approach to what LI describes Do not vary flow on the chilled water side, use 3-way valves on the heat exchanger. Choose porting to mimic the pressure drop of the heat exchanger through the bypass port of the valve. The whole system will operate with stable flow...
  9. Rputvin

    Dead head regarding fans?

    All 6 fans behaved the same? First step is verify the actual current draw and check against nameplate. It's very possible your vendor gave you overloading fans. I've never seen it, and it would be really dumb, but the EC fan space went from <5 suppliers a few years ago to 20+ now. Lots of that...
  10. Rputvin

    Dead head regarding fans?

    We usually see overcurrent issues on EC fans when the driving signal has a parameter mismatch within the fan. For example, we had a fan that for some reason was setup for 2-10V control, but with an internal scale setup for 2-8v, so when 10v was applied the fan was attempting above-nameplate...
  11. Rputvin

    Small reciprocating compressor foundation inside shipping container

    We've been doing 20ft container pump rooms for a little bit now, each one is a new learning experience. We're doing domestic shipping, so we've been cutting in doors and access hatches and things. We went down the road of shimming the underside to make the floor more stationary and to do a...
  12. Rputvin

    Small reciprocating compressor foundation inside shipping container

    All this work for a foundation and you're going to be bolting it to a 1/2" plywood floor that can have a fair amount of flex? Are you putting spacer blocks underneath to support the compressor foundation to the pad the container sits on, or are you keeping the exterior unmodified to retain its...
  13. Rputvin

    Things are Starting to Heat Up - Part XIII

    It is much more environmental friendly to mine the coal and freight it over the ocean so it can power industry making fidget spinners that are freighted back to your country to be put in the garbage, which is freighted back to massive landfills where they burn the garbage to supplement the coal...
  14. Rputvin

    Thrust Loads in Vertical Multistage Centrifugal Pump Housing

    You're looking at a Vertical Turbine Pump. While it's somewhat the same thing, the arrangement is quite different. Here's some reading to get you started, and discuss with the pump supplier's methods for internally reducing thrust loads...
  15. Rputvin

    Cool a circuit at near constant temperature

    You're essentially making a 1-tube shell-and-tube heat exchanger. There is a ton of information online to step you through the design process. Here's an example that walks you through all of the terms, including dimensional analysis, U-value, etc. which should help you understand your problem a...
  16. Rputvin

    Glycol Issue Closed loop

    City water brings more than just dissolved solids (hardness) - they treat it with all kinds of fluorides and chlorides as part of the sanitation process and preparation for drinking, depending on your local municipal setup and how the water is sourced and treated. Some city water is more prone...
  17. Rputvin

    Glycol Issue Closed loop

    Corrshield is a molybdate-based inhibitor if memory serves. It works better in systems that are not de-aerated. Nitrite inhibitors require de-aeration. You charged the system in 2014 and didn't look at the fluid for nearly a decade? Or is inspection of the fluid part of annual maintenance...
  18. Rputvin

    Cooling tower bypass into the basin VS completely bypassing the tower

    We will bypass to the tank/sump in industrial cooling (non-HVAC) loops using cooling towers. We do this as a stage of over-cooling protection to prevent condensation in equipment when the tower is able to cool below dew point - dew point in the facility is not the same as outside at the tower...
  19. Rputvin

    Removing expansion tank after system is hot

    Most of the B&G rolairtrol separators we get in lack the mesh plate that serves as nucleation sites for the air to disentrain. Aside from the tangential connections, they are an empty vessel no different than a chunk of pipe. Create a low-velocity section like LittleInch describes and it will do...
  20. Rputvin

    The Lancet pulls a fast one

    https://www.thelancet.com/journals/lanplh/article/PIIS2542-5196(23)00023-2/fulltext?dgcid=raven_jbs_aip_email

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