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ITS-90 Isothermal Towers Iss.07 – 05/14
A BASIC CONCERN
Heat siphons contain fluids. There is a basic concern that in the very unlikely event of a leak that there is a health and
safety issue.
Dealing with each fixed point in turn. Both Indium and Tin use a heat siphon containing water as the fluid at either
temperature the water is pressurised i.e. it is above 1 bar. If a leak occurred some moisture may leak out into the
insulation.
A user would notice that the cell was not melting properly.
The Zinc Isotower heat siphon contains potassium under a partial vacuum. A leak would allow a certain amount of air
to enter the heat siphon.
A user would notice that the cell was not melting properly.
An Aluminium Isotower heat siphon contains sodium under a partial vacuum. A leak would allow a small amount of
air to enter the heat siphon.
A user would notice that the cell was not melting properly.
In the unlikely event of a leak the user should contact Isotech.
The other remote possibility is that the heat siphon leaks into the cell while the cells metal is molten.
To Indium and Tin no reaction takes place with the water vapour. With Zinc and Potassium neither is affected by the
other (Ref. Hansen)
With Aluminium and Sodium neither is affected by the other (Ref. Hansen).
Again, the cell would melt badly. In this unlikely event please contact Isotech.
The Isotower wants to please you but to get the best from it you need to understand the controller temperature
settings and the top heater offsets.
