3/16" Tubing Vacuum System

Building a temperature controlled vacuum system

For the 2021 season we converted our operation to 3/16" tubing and built a temperature controlled vacuum system that uses a diaphragm pump. 

The setup worked amazing and we averaged over 1 gallon of sap per tap each day, totalling 19 gallons of sap per tap and 0.275 gallons of syrup per tap on the season.   

We used Leader clear check valve spiles with approximately 100 taps on a total of 6 lateral lines of tubing (~16 taps per line).  

Our lateral lines have fairly good elevation drop to them (over 100 feet total and at least 10 feet from the final tap in most cases).  This resulted in good natural vacuum and increased our sap yields.  Additionally, the small diaphragm pump induced additional vacuum in the lines, further increasing sap yields.  We consistently saw nearly 25 inHg of vacuum at the top of each line.   

The vacuum system operates on the following basic principles:
  1. Turn on the diaphragm pump when temperatures rise above freezing to pull sap from the trees
  2. Turn off the diaphragm pump when temperatures fall below freezing
  3. Turn on a small heat source to prevent the insulated pump box (and the pump) from ever freezing
  4. Allow for sap to bypass the pump (via a check valve) in case of power or pump failure. 
The vacuum system is comprised of the following basic components which are all readily available online from various outlets, including Amazon:

  1. An insulated box (a cooler works great)
  2. Electrical enclosure box for control system components
  3. Temperature controllers (W1209 model works great and is cheap)
  4. The diaphragm pump (Aquatec and Shurflo are very popular manufacturers) 
  5. A manifold for connecting the tubing lines
  6. A strainer to protect the pump from ice
  7. A small heat source (silicon strip heater or light bulb) 
Below is a schematic of the system we designed and built:

Below is a video explaining the system:

Below is a video of how to install 3/16 tubing:


  1. Two quick questions for you about your set-up, one, what did you use for your 12 vdc power supply? Do you have a part number? And where did you get your quick connects for your manifold? Thank you.

    1. I got the quick connect fittings (including the 3/16 barb to 1/4 quick connect stem fitting) from freshwatersystems.com.


    2. The 12vdc power supply I used is very similar to this one:

  2. Not sure if you got my first question, as I don't see it here?
    I am building a small solar system like you have and am looking for, wondering where you got the bypass valve. I am too far away to turn a valve off and on, twice a day.

  3. The bypass check valve I used is available at freshwatersystems.com


    It has a crack pressure of 0.3 psi which equates to about 8.3 inches of water, which you should easily have in drop towards the end of your tubing setup.

    1. I'll check it out.
      Thanks for your reply.
      Happy syruping

    2. You are very welcome and best wishes on the next season as well.


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