Float valve not shutting off completely

[DaveB]

I'm having an issue with my float box and I'm hoping that someone might have a suggestion. My float valve is not properly closing or shutting off sap from my feed tank and I really don't like having to manually open and close the sap going to the float box. Can anyone suggest something that I can use the will provide a better seal? I don't want to use something that is not food grade but I need something that I can put on the float box valve so that it will actually work.

[Big_Eddy]

What's your current setup look like? Pictures?
Too many float box designs out there to help without more information.

[DaveB]

I don't have a picture at the moment but I'm looking for a replacement for the rubber seal that sits on the arm of float in the float box and controls whether sap is coming in or not. The piece of rubber that is there is not sealing properly and I'm looking for something I could put in there that is food grade and will create a seal.

The evaporator is from A&A which will take me too long to get a replacement. Bascom's seems to call it "regulator packing" but I'm looking for something like this that won't take a few days to arrive:

https://www.bascommaple.com/item/elpk/float_acc/

[wiam]

Sometimes you can turn the seal over and get a better seal.

[maple flats]

Turn the seal over, but also order 2 spares. I like to get extras on all of those types of things.

[danielschauder]

Is the seal actually bad? Did your float get sap in it causing it to be weighted down and not have enough buoyancy?

[kitkat]

My brand new one from smokey lake is the same way.

[danielschauder]

My brand new one from smokey lake is the same way.

Did the float get sap in it?

[wiam]

After rereading your original post I should mention that float valves often do not shut off completely.

[Sugarmaker]

I would agree with William these are not really intended to stop the flow just slow it to a controlled drizzle.
I would ask: how big is your head tank? (This can cause the valve to not close off) How high above the pan is the head tank? ( this also has a impact on the float) Do you have a throttling valve between the head tank and the draw off box? This in line valve can control the flow therefor reducing the pressure on the float shut off system.
Or you could just have a bad piece of rubber in there.
Regards,
Chris

[DaveB]

Thanks guys for the replies. My feed tank is about 3' above the float valve and holds about 100 gallons. I also have a shut off valve between the two so I can control how much sap is flowing to the valve. In years past when the valve was closed it would prevent most of the sap from flowing to the pan. I think the rubber seal is worn out or not seated properly and so I'm looking for something that I can put in there while I wait for a replacement. But, I didn't want to use just anything. What kind of rubber can I use to make a temporary disc that might help me get a better seal?

[BAP]

It depends on what style of float valve you have. Mine will completely stop and hold it from flowing and the head tank is 6-7 feet above it. Some styles work better than others.

[wmick]

My feed tank is about 3' above the float valve and holds about 100 gallons.

You can get rubber gasket sheet material in the plumbing section of the hardware store... Probably not thick enough to make the complete disk, but could maybe add a new face to your existing one??

PS - The volume of your tank has no impact on pressure... The "Vertical Height" in inches between the top of sap in the tank to float valve determines the pressure... EG 36" of water = 1.3 PSI or 48" of water = 1.7 PSI.. (sap is slightly heavier than water, but insignificantly) Volume has no impact.

Just to clarify - Is the float valve actually overfilling your pans while you are boiling? or just when cold?

[kitkat]

didnt think of that. being new i didnt suspect a leak in the box