Pulling Sweet Off at Night and Burnt Pan

[BradWilson]

We have a 2x6 King, drop flue, reversible, oil fired right with a steam away. We've always taken a pint or two of sweet off the rig at night to add to the next day's boil to get a first draw off a little quicker.

This year we added an RO. Other than running the pans a little deeper we didn't change much. Including filtering. We use a rectangular flat panel canner but it just couldn't keep up so we bough a "half bank" filter press.

Now at night, when we flush the filter press we put what's left back into the front pan, close the pans off to keep them from mixing and clean up for the night. Two days in a row now the thermometer in the draw off channel doesn't come up to temp but there most definitely behind it. We've had to shut the rig off and draw it all off to keep from burning the pan. Well today I couldn't get it shut off fast enough. Small section of burned syrup.

Why am I making syrup behind the pan thermometer? Is the process of putting the syrup and near syrup causing that to happen? Should I draw off the "colder" syrup and add it back in behind the "almost syrup". I've been doing this a while and this is the first big "burn" for me and I haven't seen the syrup back up like this. Any and all advice is appreciated. Thanks.

** Turns out my hydrometer was bad but I’m still wondering if the process of adding sweet instead of just letting it all mix is part of the issue

[ecolbeck]

I'm not sure I entirely understand your situation, but I don't think going past syrup is what causes a pan to burn. When I draw off, the temp will sometimes spike several degrees, but the pan never burns. Is the pan heating evenly? Is there significant niter buildup?

[TapTapTap]

Is the process of putting the syrup and near syrup causing that to happen? Should I draw off the "colder" syrup and add it back in behind the "almost syrup".

I'm also confused on your process. But I can comment on the startup process based upon my own experience.

When I first fire up and the rig builds up heat, the two middle channels always heat up faster than the outer and back channels which cooks the sweet in those channels more than the others. This condition can seriously disrupt the density gradient. So my solution includes the following:

1. Pay the utmost attention to the first boil-up and be ready for almost anything since the front pan can be way out of balance.
2. I have a squirt bottle full of cold sap and a larger pitcher of sap ready to cool down the system.
3. As the middle channels start to boil, I add some cold sap to them to temper them down.
4. Then I do a couple of drawoffs to re-establish the density gradient in the front pan. This also allows me to check my valves and make sure that sweet from the back pan is flowing properly into the front pan.
5. I put the drawoff sweet into the back pan. I don't put it in the front pan since I don't want it too cool down too much. The back pan can absorb the somewhat cooler sweet much better.
6. I also use the early draw-offs to heat up my filter press and get some DE in the filter system.

On my last boil, the process allowed me to see that my drawoff manifold was plugged and gave me extra time to deal with the problem without a disaster happening. The manifold was plugged with niter from the previous cleanup.

Ken

[Super Sapper]

When yo shut down, do you just cover it and start the next boil with the level in the pans already "full"? I use wood and when shutting down it will evaporate to a lower level than when running. I do not shut valves to keep from mixing. With the lower level in the pans, the fresh concentrate added to the flue pan will push the "gradient" along until it meets the level you have set. I still get a big draw at the start and you need to watch it and open the draw off valve a little extra until you get all of the syrup out. The same happens when switching sides. Running at a higher level until that first draw could help keep enough liquid in the pans so it does not burn.

[ecp]

Starting up always seems to be a pain in the ***. But i think your issue is your "flush of the filter press" if you are using hot water to do this (you should be) that liquid is not nearly as sweet as you think. You should put that in the flue pan. A tip I've learned for making startup go smoother *with cross flow pans* is at the end of the night I acutely shut my draw off valve and let the front pan get 1 degree over syrup then shut the rig down. This 1 degree above for me gets the entire front pan to syrup and it goes right in the barrel. Them move the sweet to the front and fill the back from the flue pan. as others have said you may have niter issues and the further you push the RO the worse those will get. never understood why, but that's been my experience.

[SeanD]

Ditto on the niter and the RO being part of it. The water is squeezed out and boils off, but the niter stays through the whole process. That's why the pan is burning.

As for making syrup in the middle channels, that's the only way it works for me. I've just learned to live with it and everything is fine. I learn to watch the middle of the pan and notice what you are seeing - syrup is over there and not at the draw off channel. Like the previous posters, I make a series of draws early to pull it over. Soon enough, the temp probe at the draw climbs and spikes. I ride the spikes until things settle down.

It's not a perfect process for me. It all depends on how things ended in the previous boil. Sometimes, I'm flooding right after a draw or I'm drawing a little extra to lighten my bucket. Sometimes there's no draw at the time of flooding, but over the course of the night the front pan evaporates enough to hit syrup or get very close. On the next boil, I'm pulling that off within minutes of lighting the fire.

Each start up and boil is a little different. It's mostly observation and experience for me. Burning is most likely a niter issue, though.

[BradWilson]

Starting up always seems to be a pain in the ***. But i think your issue is your "flush of the filter press" if you are using hot water to do this (you should be) that liquid is not nearly as sweet as you think. You should put that in the flue pan. A tip I've learned for making startup go smoother *with cross flow pans* is at the end of the night I acutely shut my draw off valve and let the front pan get 1 degree over syrup then shut the rig down. This 1 degree above for me gets the entire front pan to syrup and it goes right in the barrel. Them move the sweet to the front and fill the back from the flue pan. as others have said you may have niter issues and the further you push the RO the worse those will get. never understood why, but that's been my experience.

Thanks for listening. It the OP was written when frustrated and waiting for the acid to work the pan.

The big takeaways are:

1. Keep clean - we really do
2. Let the front and back pans mix when shutting down
3. When flushing the filter press (with hot water) run it into the flue pan
4. Let the rig square everything away when firing
5. Get a new hydrometer.

Thanks alot everyone. Have a sweet weekend