+ Reply to Thread
Results 1 to 10 of 10

Thread: Pressure Switch for Small RO

  1. #1
    Join Date
    Mar 2019
    Location
    CT
    Posts
    25

    Default Pressure Switch for Small RO

    Hey all,

    Just curious what is the purpose of a pressure switch an a small (4x150) RO systems for sap?
    I see they on the occasional build, but not really sure how they would help with this type of system?
    Low pressure turn off? Over-pressure shut-down?
    Any help is appreciated.
    Thanks,
    Bryan
    2019 - First Season with a Late Start. 10 taps on buckets, block arch and 2.5 gallons of syrup.

  2. #2
    Join Date
    Feb 2019
    Location
    Murrysville, Pennsylvania
    Posts
    54

    Default

    Exactly both reasons. Can shut off on low pressure and on over pressure. This can prevent unnecessay pumping (low pressure when there is no sap left) or damage to membranes or system (on high pressure - membranes need to be flushed, etc)

  3. #3
    Join Date
    Feb 2007
    Location
    CAPAC MICHIGAN
    Posts
    716

    Default

    Quote Originally Posted by bryankloos View Post
    Hey all,

    Just curious what is the purpose of a pressure switch an a small (4x150) RO systems for sap?
    I see they on the occasional build, but not really sure how they would help with this type of system?
    Low pressure turn off? Over-pressure shut-down?
    Any help is appreciated.
    Thanks,
    Bryan
    low pressure shut off is nice when you want to leave the R/O unattended to do other things and it will shut down when it runs out of sap
    2x6 RAISED FLUE PANS
    by WF MASON
    350 taps on vac.

  4. #4
    Join Date
    Mar 2019
    Location
    CT
    Posts
    25

    Default

    How does one implement a low pressure cut of for a small hobby RO?
    I about to suits up the system and was thinking a cutoff would be perfect for an overnight RO run the evening prior to boiling. The goal would be to turn it on at night and let it run until sap is depleted.
    Any advice?
    2019 - First Season with a Late Start. 10 taps on buckets, block arch and 2.5 gallons of syrup.

  5. #5
    Join Date
    Feb 2007
    Location
    CAPAC MICHIGAN
    Posts
    716

    Default

    Quote Originally Posted by bryankloos View Post
    How does one implement a low pressure cut of for a small hobby RO?
    I about to suits up the system and was thinking a cutoff would be perfect for an overnight RO run the evening prior to boiling. The goal would be to turn it on at night and let it run until sap is depleted.
    Any advice?
    https://www.ebay.com/itm/Hubbell-Ind...f/223309859315
    2x6 RAISED FLUE PANS
    by WF MASON
    350 taps on vac.

  6. #6
    Join Date
    Sep 2017
    Location
    Wilton, NH
    Posts
    39

    Default

    The RO Bucket guys (see ad above) sell a low pressure cut-off that they sell for about $30.; installed on the concentrate line. Wire in series with your Pump, and it shuts it off when concentrate outlet pressure drops below 5 +/- psi.
    Thanks, Bill
    2017 - 3 taps hanging buckets. Turkey fryer evap.
    2017-2018 Caught a bad case of the maple bug. Built a 55 gal. barrel evap. and homemade RO
    2018 - 32 taps on 5 gal. buckets.
    2019 - New Mason 2x4 XL. 80 taps - 50 on 5 gal. buckets, 30 on 3/16 tubing

  7. #7
    Join Date
    Feb 2019
    Location
    Murrysville, Pennsylvania
    Posts
    54

    Default

    Exactly. You can buy on Amazon for even cheaper:
    Tank Shutoff (TSO) Switch for Aquatec Booster Pumps https://www.amazon.com/dp/B007XVJYZQ..._N2pNDb4ZHDMDW

    This is adjustable with a very small allen wrench to increase the top end pressure shut off. I have mine set around 110 psi.

    Video here shows where to install: on concentrate line in front of needle valve.
    https://youtu.be/s106bSrcfno

  8. #8
    Join Date
    Mar 2019
    Location
    CT
    Posts
    25

    Default

    Do you use a low pressure cutoff to turn off the pump when one runs out of sap?
    Is the high pressure cutoff to ensure the pump Donets over pressure in the event of a clog or fault?

    I would like to add a switch to turn off my pump when the feed tank runs out of sap.
    Which switch would work for this application?

    Thanks
    2019 - First Season with a Late Start. 10 taps on buckets, block arch and 2.5 gallons of syrup.

  9. #9
    Join Date
    Feb 2017
    Location
    NY
    Posts
    23

    Default

    Generally a high pressure condition isn’t a concern. Most booster pumps have an adjustable bypass built into the pump head. In addition, they can’t really get over 150psi anyways (when the bypass is Max’d out).

    To set your maximum pressure on an aquatic or similar adjustable booster pump, get it running with a pressure gauge and needle valve. Slowly close the needle valve and set the bypass pressure (usually with an Allen wrench). Once it is set correctly you should be able to close the needle valve entirely and it should hold your target pressure (~120psi).

    The low pressure switch is nice to have when running the system over night, or when you aren’t around. Even though the pumps can run dry, there is piece of mind knowing it is going to shut off if a hose blows (instead of dumping 250 gallons of sap) or you run out of sap. The shut offs need to be very sensitive and trip around 15psi. The amazon ones won’t trip until 2 or 3 psi, and it takes forever for the system pressure to bleed down that low (sometimes over an hour).

    Carl




    Sent from my iPhone using Tapatalk

  10. #10
    Join Date
    Feb 2018
    Location
    WV
    Posts
    74

    Default

    Quote Originally Posted by bryankloos View Post
    How does one implement a low pressure cut of for a small hobby RO?
    I about to suits up the system and was thinking a cutoff would be perfect for an overnight RO run the evening prior to boiling. The goal would be to turn it on at night and let it run until sap is depleted.
    Any advice?
    here is a video that should show you everything you need to know


+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts