Releaser at the snowmobile trail
I have to admit, I could stand and watch sap running into the releaser for quite some time. So, I thought I'd share a video. This comes from the woods by the snowmobile trail:
The surging or pulsing of the sap isn't actually a good sign- it means there's too much air entering the system in the woods. We know we have some leaks to fix, and plan to do a comprehensive "leak check" of the woods in the next day or two. If that goes as planned, it will make the sap flow smoother and also increase the vacuum.
We've also had some people ask us what exactly a "releaser" is and how it works. We need a releaser because our tubing lines are under vacuum, but our tank isn't (you can avoid a releaser if you use a tank that can be under vacuum too, but tanks built for vacuum are much more expensive- our tanks would be crushed if we exposed them to the vacuum we have in the tubing lines).
There are many styles of releasers; ours are a simple single-chamber mechanical style (even though there are two chambers, they're called single-chamber releasers because they only have one chamber for the sap to "dump" from). The way it works is that sap enters the upper chamber from the woods. Under normal conditions the sap flows immediately from the upper chamber (sometimes called the manifold, because it can have many sap lines entering it) into the lower chamber. It can't leave the lower chamber because the vacuum holds the "flapper valve" at the bottom of the chamber closed. When the lower chamber is full, a float inside the chamber activates a piston that shuts off vacuum to the lower chamber and vents it to outside air. The one-way valve between the chambers prevents the loss of vacuum from reaching the upper chamber, so the tubing lines and upper chamber remain under vacuum (although they will slowly loose vacuum as the sap enters from the trees). Since there is no vacuum holding the flapper valve closed, the sap "dumps" or falls out of the lower chamber into the tank. The same float valve and vacuum piston then reconnect the lower chamber to the vacuum pump again, and any stored sap in the upper chamber can flow freely into the lower chamber. This cycle repeats itself as long as sap is flowing.
Here's a quick video of sap dumping from our releaser:
Want to see this sap turned into syrup? Hit the "Visit Us" link at the top of the page for information about stopping by during the maple season, or use the "Catalog" link to check out our great tasting maple syrup for sale.