Dry line questions

[blissville maples]

So I've been adding dry lines to my latest install, I've been using the blue HD mainline which can be seen thru. What I've noticed, and maybe it was the heavy run with an abrupt freeze, but the dryline is quite full and likely will plug as other let's loose during start of next run. I was hoping to eliminate lose of vacuum to taphole during morning warmups, due to ice in mainline for first few hours. Seems most Trees always start running before they get vac to them, and this seems like a loss of production to me. Any insight or experiences would be appreciated....

[mainebackswoodssyrup]

Does your mainline have some flat spots in it causing backup? It could be undersized as well. What size lines and number of taps?

[maple flats]

That is one advantage of the wet/dry conductor method. If the main is frozen and the sap starts to flow, it uses the dry line. The sap will not over power the dry line if the wet/dry are sized properly and the short time the sap uses the dry line will be rather short. You should not need to make any changes. You may however want to revisit Steve Childs' Cornell Maple Tubing Notebook to be sure you have designed the system properly.

[Atgreene]

Is that book available from any maple dealers?

[maple flats]

Some larger dealers may carry it, I bought mine directly from Cornell Maple. They have an online book store.

[blissville maples]

Does your mainline have some flat spots in it causing backup? It could be undersized as well. What size lines and number of taps?


I have 1 1/4 wet and 1" dry 900 taps so sizing should be good. I connect them periodically throughout the bush in 3-4 spots. So if a y or valve freezes than somewhere behind it the vacuum will pick up and maintain. It does have some flatter spots however still 3percent grade or so, but it froze in a slightly steeper spot closer to the releaser. I'm wondering, since it was a fairly heavy run, that an intersection froze and for 5-15 minutes the sap traveled up into dry line and filled that as it all simotainusly froze and shut down(trees, laterals, wet and dry line)

I guess I was shocked to see this much frozen sap in dry line, I expected some not that much. I figured the only time dry line would have any liquid would be first couple hrs in morning until all slush and ice has melted from intersections.

I do have a couple saddles connecting wet and dry lines instead of 1" mainline in front of a valve at the first y(the dryline does not go both directions) because I feel the valves and y's ice jam and the saddles will not and this will maintain vacuum into wet line from dry line. Something I've decided to try this year.

[mainebackswoodssyrup]

Agreed that the wet line is sized properly or maybe even a little oversized. Something must have froze up. I'm no expert (have the Cornell book but have not read it yet) but usually your vacuum line is slightly larger than mainline. It may not help with freeze up but will transfer more vacuum when the dry line takes on some sap. Might want to look at 1.25" dry line and maybe even 1.5". We use 1.5" on our longer runs with over 700 taps.

There is a post with the link to order the Cornell book in the vacuum forum. Do a search and you'll find it.

[Moser's Maple]

Is that book available from any maple dealers?
Post #4
http://www.sugarbush.info/forums/tubing-tapping-vacuum-systems/5355-vacuum-line-size.html

[blissville maples]

I will have to look at the cornell maple book, and I guess there are alot of variables as far as freeze ups and how they happen. Was curious if others find this happen or have had it happen. perhaps I should have gone 1 1/4 dry line as well. This was the first run I've seen on this system as it is new so maybe that will not happen again or all the time

Thanks for the insight

[VT_K9]

I agree it seems odd you are having a freeze in the dry line. I am interested in using a dry line at some point to help with freeze issues. One freeze issue I learned about was the small leaks which can occur. We had a lot of icing issues last year near the releaser. While attending a short conference I learned how small leaks can lead to ice formation. Maybe you are experiencing some thing similar.

Mike

[S.S.S]

We have 1300 taps on a wet dry system using 1" lines and have no issue.

[GeneralStark]

Another thing that can be a factor is shutting the vacuum pump off before everything has really frozen up. This can especially be the case of you are using check valves in the mains where they enter the releaser.