Switching from buckets to Shurflo on solar vacuum help

[Openwater]

I've added a few more trees to tap in a low-lying remote flood plain that is totally flat and would like to put them on vacuum to increase sap production. They're all reds, so they don't produce much on just gravity into buckets. I have my 5/16" drops from last year, sterilized and cleaned for re-use and a roll of 3/16" that I purchased by mistake and never used, so I'm planning on putting the 5/16" drops on 3/16" line into a Shurflo set-up. There will be 18 trees with 20 taps. My questions are:

1. Is there any reason to replace the spouts on my drops with CV spouts since the drops are 5/16", thus already preventing most backflow into the tree during freezing?
2. Since the area is totally flat, will there be any problem with the Shurflo 4008 pumping sap "up" a few feet into the collection container? Or will this decrease my vacuum in the 3/16" line?
3. Can/should I put all 20 taps on the same line, or run 2 lines with 10 taps each?

Thanks for the advice and any suggestions.

[DrTimPerkins]

Quick comments:

- Don't use 3/16" tubing on flat ground. It will not help you in any way in terms of natural vacuum, but will reduce pumped vacuum transfer and be more difficult to clean as it ages. This is especially true on flat ground where sap can pool and form sludge which will clog any fittings. 5/16" tubing is far less susceptible to this problem.
- How did you "sterilize" your drops? It is far more likely you sanitized (cleaned and disinfected, thereby reducing dirt and microbes) the drops rather than "sterilized" (totally removed all traces of life) them.
- Assuming you cleaned the drops and sanitized them well (maybe rinsed them afterwards depending on the sanitizer used), then simply putting on a new spout is fine. Research has shown that sanitizing is pretty good (for maintaining sap yield), replacement is generally better, especially with CVs, but doing both is just a waste of time and money (in terms of sap yield).
- If you're using pumped vacuum, the "strive for five, no more then ten" rule is best. Most high-yield production is less than that, typically 2-3 taps per lateral, with no more than 5.
- The Shurflo will pump uphill a bit without greatly affecting vacuum on the other side. These types of systems always have some pulsation going on, but it is unlikely to be greatly affected unless you're trying to push uphill a good bit.

[bmbmkr]

3/16 on flat ground is not ideal as Dr. Tim says. Mike Heasley, a retired Physics professor from WVU did some experimentation with a flat run of 3/16 the end of a down hill run and the friction overcomes the natural vacuum very quickly. However, with one or even two laterals and a shurflo, you'll have way more sap than you ever had in a bucket, and maybe more than natural vacuum. I'd put em all on the same run. The shurflo will pull em. I've got two 1600' laterals with 44 & 48 taps running straight down a steep hill, and they both pull 28"/Hg, they both produce sap for two days even if it doesn't freeze.

I found I didn't need CV spouts on 5/16 drops. I started 6 years ago with mostly 3/16 laterals and drops. I did have one 5/16 lateral, and had both CV and economy spouts on it. I went out and watched the sap draw backwards when it began to freeze in the evening. The sap in the 3/16 drops would pull all the way up the drop and back into the tap hole. I had the one 5/16 lateral and the sap never made it more than 10 inches up the drop (I make 30" drops).
I had planned on using all CV spouts on the 3/16 lines the following year, but I found the discussion on the forum here suggesting 5/16 drops on 3/16 laterals. Some people didn't like the idea because they didn't want to spring for another tubing tool. I started out with a single hand 5/16 tubing tool. I found this site, read about the benefits of, and decided to use 3/16 since most of my woods are on steep hillsides. I took a 1 1/2" piece of 5/16, cut it lengthways and slid it over the 3/16 tubing and the jaws hold it just fine. I'll tell ya I wasted a lot of time, running 3 1/2 miles of tubing, up to 600 taps now with that single handed tool. I finally bought a couple double hand 3 and 5/16 tools used this summer. I was hesitant to switch out all those drops,* but once I found the 3-5-3 tees from CDL, it was a breeze.
I increased from 125 to 250 taps that next season, replaced the 5/16 lateral with 3/16, and put 5/16 drops on all of em. Our season is pretty short down here in southernmost Ohio, We tap early January and hope for the best about the end of Feb. I've seen sap run for 10 weeks out of a 5/16 drop on 3/16 tubing. I had a tree at the top of the hill uproot the first of March, when it fell, it fell on the spout. I pulled all my other taps that weekend and a few weeks later when I went up there the sap was still running down that lateral. I have a video of it on my FB page.

Two things with the CV spouts A: I have had dozens of the clear plastic leader spouts crack, and they suck air and you lose your vacuum, whether natural or on a pump. Both the economy and CV spouts have cracked here. I'm using soft faced 6 oz hammers to tap with. I don't know if they are freezing or what, but I've not been satisfied with them- I went back to CDL white health spouts last year. I have had zero issues with them. That's what I used the first year, and will until I find something better.*
B: the little ball in the check valve will get sticky with sugar and sometimes it will stick. Again we have warm spells down here towards the end of the season and that could be a factor.
I've been running about 60 taps, 4 laterals on 3/16 into a shurflo 4008 the last 3 years, 45 sugars and 15 reds. It pulls 26 in/Hg. I had two days last season with 150 gallon a day out of those trees and that little pump. Most days over 100 gallon. One of those four laterals is all but level, 17 taps, and lower than the pump, it pulls uphill about 4 ft over 100ft from the last tree. I'm about to run another 1200' of 3/16 this year on 200 silver maples, they are flat and grow along our creek bank, They bud out so earlier than my sugars and reds, so there's no way I can justify running 5-7 taps per lateral on 5/16. It'd take 5x more tubing. I've got two more shurflos to go on these trees. I'm no expert, goin into my 6th year, and have had at least one 12V pump on some of my trees every year. I'm just lettin ya know what has worked for me. Now my 3/16 laterals on the hill side come straight down the hill and into the mainlines. I worked really hard not to have any flat runs after the last tap. I've used a transit to shoot my mainline paths.

If you keep your lines tight and leak free, and clean that lateral as SOON as you pull your taps. I think you'll be happy with your shurflo set up. The newer 4 diaphragm shurflos pull much better vacuum than the 3 diaphragm everflo and seaflow pumps.

Those 20 taps may very well turn into many many more in just a few years! Good luck.

[Openwater]

Wow, lots of good practical info. Thanks a bunch.
Makes me feel a little more confident about trying the vacuum on these reds in the flat.
Will just have to get that roll of 5/16 and fittings.

Is the double fitting tool for installing T's essential? Or is it possible to push the T's together by hand if I'm only doing 20?

Regarding the solar power, I'm not an electrician, but I can do simple wiring. Do you know what the furthest distance would be that I could have the solar panels from the controller and battery? I'm using a Shurflo 4008, have (2) 100w solar panels (200w total) and am planning on using 10ga wiring from panels to battery/controller box.
Thanks again for the help.

[MISugarDaddy]

You will want/need the double fitting tubing tool to fully insert the T's into the 5/16" tubing. It makes inserting the drops into the lateral easy after you have pulled the lateral tight.
We operate 4 Shurflo 4008 pumps at different locations in our woods and all of them sit close to the ground and easily pump sap into the tanks located above them. One of the pumps actually pumps sap up approximately 6' to a 3/4" line that crosses a trail before dropping into a tank located 80' away.
Good luck with your project.
Gary

[Biz]

I tend to go low budget on some things when first starting out. The tubing tool makes things easier but with only 20 taps it is not essential. We did 80 taps on tubing our first year and installed all fittings and taps outside using a thermos of hot water. Dip the end in for 10 seconds and push it on. Didn't have any leak problems.

For the solar wiring, 10 gauge will work perfectly fine, and if you can swing it, that is great. If a smaller gauge wire is used, if will still work but won't be as efficient due to wiring losses. Your battery will still charge but it will take longer. I used 200' of 14 and 16 gauge extension cords to my 200W solar panels. Yeah, I know the wiring is undersized, but it fully charged my two paralleled batteries to 14 volts on a sunny day. Now after 4-5 years of use, it is time to think about replacing my marine batteries since they don't hold charge like they did when new. Or maybe I can squeak just one more season out of them...

Dave

[wobbletop]

I'm using a Shurflo 4008, have (2) 100w solar panels (200w total) and am planning on using 10ga wiring from panels to battery/controller box.


100w at 12V is only 8amps. Normal house wiring is good for 15A. I'm not sure why you would need 10gauge wire. What am I missing?

[Biz]

For low voltage DC, the wire size should be larger than for AC for a given current to reduce wiring losses (or voltage drops across the wire).

A solar charger puts out something closer to 20 volts. For a 10 amp load with 100' of 14 gauge wire, you lose about 6 volts (30%) round trip which brings you down to 14 volts at the solar charger input. Barely enough. If you were using 115V AC power, the same losses would give you 109V, which might not make a difference. Going to a heavier wire gauge decreases the losses. Hope this makes sense.

Dave

[Openwater]

Thanks for chiming in, Dave. I read a lot of your past posts about solar charging systems.
So with (2) 100w panels, a deep cycle marine battery running a Shurflo 4008 and maybe a silicone heating element; would I be ok running 200' of 10g wire from panels to controller?
Will the monocrystalline panels still work much on cloudy days? I've never used solar panels for anything.

[Biz]

200 watts of solar panels is more than enough for the 4008 pumps. I normally see less than 20 watts consumed by the pump. Your heater will likely take more power than the pump. Any solar panel will produce less power on a cloudy day than on a sunny day. Good positioning of the panels can help. I have seen a new deep cycle marine battery run the 4008 pump for about 35 hours with no charging, so you have to hope that there is enough sunlight to carry through multiple cloudy days. I think you are doing everything possible in this area, let us know how it works out.

Dave

[mudr]

how do folks deal with freezing if the diaphragm pump is located below the tank and it has to pump upwards? doesn't the pump out line freeze solid?

[Biz]

It will freeze up. You need to drain the line after the pump shuts off. One way to do this is place a tee in the pump outlet line, and add a ball valve to drain the line when pump shuts off. If you are using a controller for the pump, for the valve you can use a normally-open motorized ball valve wired in parallel with the pump. When the pump turns on, valve energizes and closes. When pump turns off, valve opens and drains line. I have set up systems like this with the S3 controllers as well.

Dave

[Openwater]

Ok, I didn't think of the pump being lower than the collection tank with freezing. I assume if I put the pump higher than the tank and the outflow just drops into the tank, I shouldn't have problem, right?
Do you have a diagram showing how to wire the motorized ball valve into the temp controller? In case I can't get my pump high enough to drop outflow into collection tank; remember, this is in perfectly flat woods. I assume its safer to have sap freezing in the in-flow/lateral line as opposed to the out-flow. Obviously, raising the pump too high is going to cause sap to collect in the lateral leading into the pump manifold.

[Openwater]

I got everything I need for the solar vacuum set-up except the battery. I got a MPPT solar controller which says it can handle sealed/flooded/gel/AGM and lithium batteries. I know you said a good lead acid deep cycle marine battery can run the 4008 pump for 35 hrs without recharging, but would one of the other more-expensive type batteries work or give better performance/longevity during stretches of cloudy days?

[Biz]

The pump run time is based on battery amp-hours. A battery with higher amp-hour rating will run the pump longer than one with a lower amp-hour rating. I would be interested in how well a lithium battery performs compared to a lead acid. I bet for equivalent run time, the battery would cost 3-4 times (or more) what a marine battery costs. They are much lighter and should last longer.

Dave

[highlandcattle]

We used Trojan lead batteries on our off grid farm. Lasted 10 yrs.

[Openwater]

I got my pump plumbing and electronics assembles in a tote/bin and solar panels mounted on an adjustable rack/stand.
Now, since this is my first attempt at a tubing system on mech vacuum, I got some questions about running the laterals, installing drops, etc.
I plan on pre-assembling the drops w/spout on one end and T on the other, probably making them 32-36". If a drop is too long when tapping, is it ok for it to form a loop/trap below the 5/16 lateral? I plan on the pump running as long as there's sap flowing (temp controller set to turn on pump above 33-34 degrees F).
Will there ever be frozen sap in the drops or laterals if the pump is running as long as sap is flowing? ie, the pump doesn't shut off until it gets down to 32 F.
Thanks for the input.

[Biz]

I set up controllers to turn off at 29 or 30 degrees F. I have found that sap is usually running in lines for a little while below freezing, so pump is kept running until sap stops flowing.

Dave

[Openwater]

Sap still flowing at under 32 F? I didn't know that could happen. I guess I still have alot to learn about maple tree physiology.
The only other conundrum I'm facing is this issue of the recirc line on the Shurflo. I've got my (2) 5/16 laterals (less than 300' each, 10 taps each) going into a 3 point star fitting on the pump intake, so I do have an extra 5/16 point on the star to plug in another line for the recirc, but, won't this lead to residual recirculated sap freezing in the pump once it shuts off at 29-30 F? Approx how much vacuum am I giving up by not having the recirc line?

[Biz]

My theory on the sap flow is that the tree and sap in the tree takes a little while to freeze after air temp drops below freezing, so sap continues to flow a little longer. I have seen lines still running in the early evening when air temp has dropped to a little below freezing, while nearby buckets where sap is exposed to air are stopped and frozen.

You may lose a little vacuum from the recirculation line. The vacuum loss can be minimized by keeping flow just low enough to keep the diaphragm wetted to draw sufficient vacuum. Your conundrum is a valid one, the recirculation line will likely not freeze so the pump will always have sap in it. You could turn off the recirculation once sap has started flowing well, if that is possible, since it is mostly effective after pump first turns on. My systems have a sap purge function which automatically purges sap from the pump for a few seconds before shutting it down - this allows a recirculation line to be left on. Something similar could be done with ball valves if it is manually turned on/off.

Dave

[DrTimPerkins]

Sap still flowing at under 32 F? I didn't know that could happen. I guess I still have alot to learn about maple tree physiology.

It's quite simple. Air temperature and tree temperature are not always the same thing (and frequently are not). Air temperature can change rather quickly...tree temperature is buffered and thus changes more slowly and unevenly (not surprisingly considering the tree is about 70% water). Not only is there a difference in temperature between air and the tree, there is considerable variation in temperature even within the tree. South sides of trees and fine branches will thaw faster (especially if it is sunny), north sides and larger branches will thaw more slowly.

It is somewhat more common for sap to stop flowing on tubing systems because the tubing freezes than because the tree freezes. Different portions of the tree may be thawed and exuding sap while other parts are freezing and taking up water (from the soil) at the same time.

https://www.themaplenews.com/story/why-the-sap-may-not-always-flow-well-in-the-early-season/362/

[Openwater]

the recirculation line will likely not freeze so the pump will always have sap in it.
why wouldn't the line freeze when the pump shuts off at 29F?

Ok Dave, so if I do this recirc line thing and put a length of 5/16 onto the 3rd point of the 3-point star fitting and the other end in my 35 gallon collection tank with some kind of in-line valve to restrict flow to a trickle, how do I keep the other end of my stiff 5/16 30p in the bottom of my 35 gallon tank? I'm always a little leery of putting any foreign objects in the collection tank for fear of introducing germs/bacteria/infections into the sap.
I figure each day when I empty the 35 gallon tank, I can just leave a little residual sap in the bottom for the recirc line to use.

[Biz]

why wouldn't the line freeze when the pump shuts off at 29F?

Ok Dave, so if I do this recirc line thing and put a length of 5/16 onto the 3rd point of the 3-point star fitting and the other end in my 35 gallon collection tank with some kind of in-line valve to restrict flow to a trickle, how do I keep the other end of my stiff 5/16 30p in the bottom of my 35 gallon tank? I'm always a little leery of putting any foreign objects in the collection tank for fear of introducing germs/bacteria/infections into the sap.
I figure each day when I empty the 35 gallon tank, I can just leave a little residual sap in the bottom for the recirc line to use.

I would attach something like a stainless steel fitting to the end of a small hose hose and drop it in the tank. If there is a drain, you could attach the recirculation hose to the drain valve, if you don't want something extra in the tank. Or you could connect up a rigid suction line from PEX or PVC. The sap already has bacteria in it by the time it reaches the tank.

Dave

[DRoseum]

Dr. Tim - is there much research on recirculation lines on small diaphragm pump vacuum systems and effect on yield?

Does it increase yield? Decrease yield? No statistical significance?

[DrTimPerkins]

Dr. Tim - is there much research on recirculation lines on small diaphragm pump vacuum systems and effect on yield?

Does it increase yield? Decrease yield? No statistical significance?

No need for research. Recirc (if done properly) will increase vacuum. Increased vacuum will increase sap yield by 5-7% per inch Hg of vacuum.

[Openwater]

Is there any quantitative data or even approximations regarding the realized gains from using recirc lines to keep a diaphragm pump 'wet' vs letting it run 'dry'?
I'm just curious about how much sap production I'd be missing out on if I choose not to run the recirc line. I'm still assuming that any vacuum will make my reds produce more than last year's 5/16 drops into buckets.

[Biz]

You will still get good vacuum from your diaphragm pump without a recirculation line. I have been running one or two diaphragm pumps every year without recirculation lines and get over 20" of vacuum on my red maple lines. The recirculation line gets you a "jump start" in the morning, so you get good vacuum quicker rather than waiting for sap to start running to generate the vacuum. Once running well, the recirculation line isn't helping much. The reds seem to respond well to vacuum, even with a small amount. I have not had any success with buckets on reds.

Dave

[DrTimPerkins]

You will still get good vacuum from your diaphragm pump without a recirculation line. I have been running one or two diaphragm pumps every year without recirculation lines and get over 20" of vacuum on my red maple lines. The recirculation line gets you a "jump start" in the morning, so you get good vacuum quicker rather than waiting for sap to start running to generate the vacuum. Once running well, the recirculation line isn't helping much. The reds seem to respond well to vacuum, even with a small amount. I have not had any success with buckets on reds.

All of this is correct. Recirc will help. These types of pumps are designed for moving liquid as opposed to air. They will move air (to generate vacuum), just not terribly efficiently. Wetting increases their performance, but once sap is flowing, recirc is redundant.

Red maples seem to be considerably more reliable on vacuum, however we still see the occasional dry or low-producing tapholes even on vacuum. In general however, on vacuum, you'll get good amounts of sap.

[Openwater]

Thanks for that reassurance. I think I'll forego the recirc line for this year since the tubing and mech vacuum is already new to me.
I thought my reds did pretty well last year on the buckets, but I didn't have much to compare to except for the stingy black walnuts on buckets the year before.
Heck, even if I only get 10inHg of vacuum, that's still 60% more sap production than I had on the buckets, right? For my 20 red taps on the tubing, do you think my 35 gallon collection tank is big enough if emptied every 24 hrs?

[RC Maple]

While I'm not switching all my taps from buckets, I am tapping my own woods for the first time. There are only 6 sugars and 3 silvers big enough to tap this year. The silvers though are big and have multiple trunks of tappable size. I will have 13 taps this year on these trees with three runs of 5/16. The low areas that hold water have always kept me from being able to count on carrying sap by hand to the sugarhouse. My solar powered system will have a manifold with 5/16 hose barbs for my 3 lines. I have a recirculation valve and will put a 3/16 hose barb off of it and run a 3/16 length of tubing into the tank to restrict the flow vs a length of 5/16. When sap is running and the system working, I can shut the valve off. That's my plan...

[eseerup]

We had 2 set-ups last year. One was in under the woods, the other out in the open. Significant difference in charging ability of the two areas. Both had 2 - 100 watt panels. The open set-up with ability for full sun was always charged (even when cloudy). The other we did bring the battery home 2 times during the season and charged it just to make sure. Set-up was pretty awesome. The woods set up, we ran 3/16 with 20 trees +/- on 5 lines had 77 taps. It produced almost 19 gal/tap for the season.

[Openwater]

I'll have my Shurflo 4008 also on 2 - 100 watt panels. My temp controller will turn pump on above 33 deg F which means, here in Central PA, it may not dip back below 29 to shut pump off for days. If my pump runs non-stop for multiple days/nights, do you think the solar panels will be able to keep the battery charged enough to support the non-stop pumping? I'm not an electrician, but I've read the pump will draw around 2 amps on my 12v deep cycle battery. I'm hoping the solar panels will be able to charge the battery faster than the pump drains it; especially if the pump runs all night when no sun's on the panels.

[Biz]

The 4008 pump will draw between 1.0 - 1.5 amps on a vacuum line setup. How long it will last depends on size of the battery and how much solar charging you can get. My guess is with a good new deep cycle battery and 200 watts of solar, you shouldn’t have a problem with the pump running continuously for a few days straight. There are differences in marine batteries so get one that has a higher Reserve Capacity (RC) rating for longer run time.

Dave

[Openwater]

The battery I'm looking at is around $110 with 675cca and I think 210 min RC; It's a size 29. Does the ah rating matter much? What information does that tell me?

[Biz]

The larger of my two marine batteries has the same ratings. As a rough estimate, take RC and divide by 2 for amp-hours, so that is 105 a-h. For a 1.5 amp pump that gives you about 70 hours of run time. Not sure how exact this but it is in the ballpark. You lose a little capacity over time as the battery ages, much like a car battery does.

Dave

[Openwater]

One more question about my first vacuum tubing set-up. I want to put a vacuum gauge on the first tree in the run, but the lateral that's looped around the end tree is about 8' off the ground. When I put the vacuum gauge on the T at the end of the lateral, will the gauge still operate normally if it's hanging upside down from the "overhead" lateral? Or does it need to be in an upright orientation to function correctly?
It's a B-II glycerin-filled gauge.

[West Sumner Sugar]

Ideally you would want a gauge at your pump and another at the highest point at the end of your line.

[Openwater]

Update on my vaccum system. 20 taps total, 10 taps on 2 laterals, 1/2 of taps are below lateral. Lateral lengths are 175' and 215' and are almost flat - maybe 3' of drop from 1st tree to pump.
Vacuum gauge on end of each lateral pulls about 11inHg when pump is dry and about 15inHg when there's sap going thru pump. There's never a full, constant stream of sap going thru pump since there's only 20 taps.
Bubbles in laterals barely move and sometime move backwards.
I can see bubbles going up drops to T in lateral; almost all drops have sap filling the upslope of the loop before the T.
Any advice on getting higher vacuum w/o adding the recirc line?

[NhShaun]

Try pinching off one line at a time and checking vac for the other line. That will at least narrow down the leak search 50/50 if that's the issue. The other issue could be the below lateral tapping spots.

[Openwater]

Wouldn't I see fast moving bubbles at fittings if there were leaks? I checked all the fitting locations. And I assume if the tap was leaking I'd see fast bubbles moving up the drops to the T.
I'll trying pinching the lines and see if the vacuum changes on the gauges. I assume if there's no leaks, the gauge readings shouldn't change, right?

[Super Sapper]

One thing to look at would be to make sure the last few feet of line are sloping to the pump and not close to level.

[Openwater]

Actually the last few feet are pretty level. And the one lateral actually loops upward a little bit inside the bin/tub/tote before going down onto the barb on the star fitting. I thought even minimal vacuum would overcome that slight amount of short "elevation"

[Openwater]

Since my first solar shurflo vacuum system doubled my production last year, I decided to add another 25 taps onto a second shurflo vacuum system.
This new system is 25 "mountain" trees compared to my original 20 maples in a floodplain.
The few reds I used to have on buckets on the mountain seemed so much more stingy and hit-or-miss with their sap production, so I'm hoping that putting some mechanical vacuum on them, I might get them flowing a little better.
They're also at a higher elevation than the ones down in the floodplain.
Will there be a difference in timing of sap flow (earlier, later, etc) due to the elevation difference? Or is it sill mainly a difference in temperatures?
Thanks for all the help, advice and suggestions!

[Biz]

You will definitely get better sap production from the red maples on vacuum. I have experienced the same "hit or miss" sap yields with buckets on the reds. Now with vacuum the yield for red maples is similar to the sugar maples. Still a little less sap and slightly lower sugar content since they are mostly woods trees with small crowns. Hoping my thinning efforts will help, eventually.

Dave

[DRoseum]

University of Vermont did a study that showed reds yield as much syrup per tap as sugars when under comparable high vacuum.

https://youtu.be/ncnlc3tLBt8

I had similar experience with reds when on buckets. Moving to vacuum was a game changer with at least double the yield if not more!

[Openwater]

I've been pretty impressed with how my 25 red maples on the mountain have produced putting mechanical vacuum on them.
I've been getting anywhere from 20"Hg to 27"Hg, depending on how I adjust the recirc line, on the gauge in the bin attached to one of the star fitting ports and about the same vacuum on the gauge at the 1st/top tree.
I've got all 25 taps/drops going into one 5/16 lateral running into the shurflo.
I'm just wondering if I'd gain much for next year by running 2 or 3 laterals with 12 or 8 taps on each vs how I have it now with all 25 on 1 line.