Why so dark syrup with 2x4 drop flue?

[Swampmapleman]

I have a leader 2x4 drop flue with auf and my first 4 gals is very dark. Its dark robust on the gauge. I know early sap has been known to be dark but ive run 400 gals through it and its not lightening up. I have cleaned the pan after making 2 gals and saved the sweet. When firing back up i canted off the niter and dumped back in. Next 2 gals came out same color. The unit does 20 gals an hour and the syrup pan boils very even. all my tanks are clean. Why is my syrup so dark? Is it the small pan causing this?

Thanks
Matt

[Daveg]

Matt, Did you get a sugar content reading of your sap? I don't know your "sweet" inventory, but 4 gallons of syrup from 400 gallons of sap is obviously weak. Have you sweetened this rig before? If it's full of 10-40% sap now, then your boil times going forward will drastically shorten and the syrup will lighten.

[Swampmapleman]

I have drawn off 4 gals so far with syrup still in the pan. The early sap was around 1.2 and i havent measured since. As of last night 400 gals went into the thing. My sap is not great since 90 percent of my trees are reds. But 5 gals of syrup so far and being dark is discouraging. I can also say that the rig has been run 7 or 8 times for 4 to 5 hour boils. im thinking thats where the dark syrup is coming from.

Matt

[Maplesapper]

We boiled 3 times to sweeten the pans and produce 5.25 gals of syrup.
Our runs were very sketchy as there is still so much snow.
Syrup started light, but finished quite dark for this early.
I believe the multiple firings are the culprit.