Frozen sap tank pipe

[mspina14]

I have a 240 gallon stainless steel tank I use for a sap holding tank.

It also serves as the head tank for my evaporator.

15417

The PVC pipe that runs from the bottom of the sap tank to the evaporator is frozen, and I can't get sap from the tank to the evaporator.

15418

I've tried wrapping the PVC pipe with an electric heating tape and covering that with a rubber insulation. But still no sap.

Any suggestions on how to fix this problem greatly appreciated.

Thanks.

Mark

[anchorhd]

If it is frozen, run tubing attached to an electric pump from the evaporator end of the pipe toward the tank. Once you hit a stop, pump sap while pushing the tubing toward the tank. It will break the ice and start running and clear itself.
Or try a hair dryer to thaw the line.
I read somewhere pvc ball valves can be a problem due to freezing.

[sugarwoodacres]

I use a heat bgun when it happens

[mountainvan]

Do like anchorhd said but with hot water.

[maple flats]

That's why my line from the head tank to the evaporator is all copper, I use a torch if necessary.
At this point, I suggest you just leave the heat tape plugged in, verify it is getting warm, and then leave it for a few hours. It will thaw enough to run. It looks like you have no RO (concentrate takes more cold before it freezes), keep the heat tape turned on until the sap is almost gone, then remember to turn it off.

[lakeview maple]

I use a heat tape that's precoiled , it fits around the feed line , I just plug it in early morning before I boil, and I also have the handy dandy heat gun backup.

[VT_K9]

I have used a torch on PVC, but proceed with caution and don't keep it in one place long....you'll leave a BIG clue you were using a torch. As much as I may agree the cleanout is a nice thing to have, I would change your plumbing. I would elevate the tank and put a metal ball valve immediately out of the tank (with a nipple). (Metal ball valves can be purchased with solder joints so they do take the heat, but keep them closed so the parts don't warp) Then I would go into a Street Elbow to help minimize pockets for sap or bacteria to build up. I would also establish a drain by pass inside so you can clean the tank with hot water after every boil when it gets warmer out (or everyone if you can).

I don't know your tank outlet size, but mine are 1 1/2". I would stay 1 1/2" until you get inside the shack and then reduce to what ever you need on the final drop to the float (mine would be 1 1/4" I believe). Make the reduction on the drop and this will reduce freezing or bacteria prone areas. I would also use a rubber/urethane plug on the inside of the tank. I do this on my holding tank in the woods and it works great. It keeps the valve and elbows from freezing and possibly cracking.

Mike

[SeanD]

I use a heat tape that has a thermostat built into it. On/off at 38 deg. I use them on my IBC totes and I wrap the tape around valve and neck to keep that part from freezing. So far that has worked for a few years.

I have a separate head tank and empty after each boil. Last year I accidentally left a small amount of sap in there - enough to fill part of the flexible 1" line I have coming in to the float. That was such a PITA to thaw with my wife's hair dryer (that's our little secret). So, this year, I'm going to put a quick connect at the box, so I can tip it down into a bucket at the end of the night in case I do that again.

[wnybassman]

I use a heat tape that has a thermostat built into it. On/off at 38 deg. I use them on my IBC totes and I wrap the tape around valve and neck to keep that part from freezing. So far that has worked for a few years.

I have a separate head tank and empty after each boil. Last year I accidentally left a small amount of sap in there - enough to fill part of the flexible 1" line I have coming in to the float. That was such a PITA to thaw with my wife's hair dryer (that's our little secret). So, this year, I'm going to put a quick connect at the box, so I can tip it down into a bucket at the end of the night in case I do that again.

I valved it to be able to drain out the head tank completely if needed.

15420

[mspina14]

I have used a torch on PVC, but proceed with caution and don't keep it in one place long....you'll leave a BIG clue you were using a torch. As much as I may agree the cleanout is a nice thing to have, I would change your plumbing. I would elevate the tank and put a metal ball valve immediately out of the tank (with a nipple). (Metal ball valves can be purchased with solder joints so they do take the heat, but keep them closed so the parts don't warp) Then I would go into a Street Elbow to help minimize pockets for sap or bacteria to build up. I would also establish a drain by pass inside so you can clean the tank with hot water after every boil when it gets warmer out (or everyone if you can).

I don't know your tank outlet size, but mine are 1 1/2". I would stay 1 1/2" until you get inside the shack and then reduce to what ever you need on the final drop to the float (mine would be 1 1/4" I believe). Make the reduction on the drop and this will reduce freezing or bacteria prone areas. I would also use a rubber/urethane plug on the inside of the tank. I do this on my holding tank in the woods and it works great. It keeps the valve and elbows from freezing and possibly cracking.

Mike

Thanks to all for your suggestions.

I have had the heat tape on for about 5 hours now. I just went into the shack and opened the valve and the sap flowed. So it seems like the heat tape did it's job.

Mike - Great suggestions. I'm already thinking about how to rework the plumbing as you suggested. Also, great idea about the rubber plug. My sap tank drain is 1 1/2 inches. I will look for a rubber plug to put on top of the drain inside the sap tank to prevent any sap from entering the pipes and potentially freezing.

Mark

[maple flats]

Right after my tank I have a T and 2 ball valves plus a SS butterfly valve. One leg of the T points down and drains into a sink, the second is close to but down stream towards the evaporator and the SS butterfly valve is before the T. When I shut down, the tank is usually empty, but if not, I close the butterfly valve, open the drain valve and open the valve towards the evaporator. I then close that last valve, then close the drain valve. Now, if things freeze, I only have a few inches to thaw between the tank and the butterfly valve. That type of valve if it's SS will not break when frozen as long as the expansion in the pipe can push into the tank. A ball valve, with water or sap in it will burst when frozen.