Pumping within a vacuum

[Ultimatetreehugger]

Ok Traders,
I once again come to you to be smarter (or better at Google) than I.

Is it possible to pump sap within the vacuum system?
Instead of pulling sap up hill with a sap ladder I want to attach a vacuum "booster" to end of a small section of mainlines and pump sap up a 12 ft rise to my wetline with a shurflo pump(I have power access). My dry line would be connected to the vacuum port on the booster.

Will this work? Can you pump sap within a vacuum?

My goal is to eliminate vacuum loss experienced while using sap ladder or sap lifter.

Thanks in advance!

[Brian]

The only thing I can think of is a cdl dog house releaser and a pump line to your next tank. Run the pump line sloped to the tank and have the pump, pump up to the pump line. I don't know how many taps we are talking here.

[Ultimatetreehugger]

350 taps. It's almost a mile to the releaser so I'm trying to avoid that. Which it why I was gonna try connecting it to the wetline.

[Brian]

maybe a vac tank with a small vac line sucking out of the tank to keep the vac up.

[Brian]

That could run 800 gallons on a good day. I think a releaser would pay for its self and with the dog house no tank would be needed.

[johnallin]

Ok Traders,
I once again come to you to be smarter (or better at Google) than I.

Is it possible to pump sap within the vacuum system?
Instead of pulling sap up hill with a sap ladder I want to attach a vacuum "booster" to end of a small section of mainlines and pump sap up a 12 ft rise to my wetline with a shurflo pump(I have power access). My dry line would be connected to the vacuum port on the booster.

Will this work? Can you pump sap within a vacuum?
My goal is to eliminate vacuum loss experienced while using sap ladder or sap lifter.
Thanks in advance!

That's what CDL's Sap Lifter does. I have one here and it works just fine - as long as the vacuum doesn't drop of below 25" - get below that and mine has a hard time pulling the disc up to close off the drain at the bottom of the tank. Been chasing some leaks this week - as a result it's acting more like a sap ladder with the lower disc not under enough vac pressure to seal properly.
If everything is tight, say 26-28"HG it works flawlessly It uses a float on an arm much like a toilet tank.
When the tank fills, the float arm rises, pushes up a pin and breaks the vacuum in the tank allowing sap to be pulled up as in a ladder. It takes about 10 seconds to empty the tank. When the float arm drops - with the dropping sap level in the tank, the pin falls (gets sucked) back down and vacuum is re-established in the tank. Sap then rushes in and the process repeats itself.

[TapTapTap]

There's a little confusion on sap lifters. CDL has a sap lifter that acts under vacuum alone to lift the sap to a higher elevation. They also have a "High Vacuum Sap Lifter" which uses a 1/2-in-dia 12V DC in-line pump to push the sap totally within the vacuum system. The advantage of the high vacuum system is that it shouldn't have a freeze up problem since it is contained inside of an insulated doghouse and heated by a propane pilot light. I have one in my woods which runs off from AC with a DC inverter inside the doghouse and is also available in solar. It came as a dual pump running in parallel for a higher flow. However, I modified it to the 2 pumps in series to provide more vertical head capacity (CDL now offers the in-series option). The pumps are within a canister and activated by a float switch. There are no checkvalves at the outlet side of the pumps so that the sap flows back to the tank to prevent freezing. The 1/2" line minimizes the volume of flow back so that the pumps can cycle since they're not duty cycle rated. The vertical head is rated at about 20 ft and I'm doing about 25 ft with the pumps in series. I have about 550 taps on it which is way beyond the CDL rating.

So, in response to the OP - yes, you can pump within the vacuum system and even do it with a low DC setup. The pumps are Seaflo 280s which are only about $40 each. I think your problem will be to prevent freezing which is done nicely with the CDL system.

The instruction manual is available online. Also, I didn't follow their plumbing instructions exactly since I essentially have a dry line venting across the pumps to allow the vacuum to be maintained on the field side as the pumps are working.

Ken