[PerryBee]

I've had this tank for years and am very happy with it. Something I've noticed is that as it fills up with honey, there is a sudden "thump" as the height/weight of the honey nears the top of the tank. What seems to be happening is the inner tank expands and the water level in the jacket is affected. There is no leaking in either. Does anyone know if there is a conical bottom in either the jacket of the inner tank or the very bottom of the over all tank? It seems like the "cone" is inverting or something. As the honey is drained out and the level reaches the bottom, the same thing happens in reverse as the water pressure in the outer tank pushes the "cone" back.
Anyone else notice this on their tanks?
Hope I explained this well enough.

 

[crofter]

I think you have identified the source. I have a half dozen sealed empty barrels and one of them gives that bong morning and night on a lot of days. Snap disc thermostats work the same way.

 

[G3farms]

Hey there Perry

I would say it is the bottom of the inner tank giving way to the weight of the honey.