Propylene-glycol-water mixtures are commonly used as the heat transfer fluid. An
antifreeze concentration of about 40 % of glycol in the mixture prevents the system
from damage. even at temperatures of -21 °c, the system remains in an operable state.
temperatures below this protection point will cause the formation of ice pulp, which
however is not able to destroy tubes and piping.
However, today's high-end flat collectors and direct-flow vacuum tube collectors may
cause the premature degrading of conventional heat transfer fluid at high stagnation
temperatures. In order to prevent this process, the operating pressure of the system
can be limited to 4 bar or a high-temperature-resistant heat transfer fl uid can be used.
Important notice about the use of heat transfer fluids:
Only use heat transfer fluid which is suitable for the system it is used in
All parts of the system that come into contact with fluids must be glycolresistant
Concentrations of more than 50 % of glycol are to be avoided in order to achieve optimum efficiency
Tyfocor® L and LS are not subject to the ordinance of