Hose to venturi control unit

[n/a]

There is this small hose that split off from the heater hose and connects to the venturi control unit.  Can someone tell me what is the purpose of this hose?  Are we running hot water in the venturi control unit?

Louis 70 280sl Red Auto

[A Dalton]

Low ambient temps and venturi effect can cause throttle plate freeze-up of any accumulated moisture carried over from the  engine crankcase vent tube.
 This was a later vesion production modification that can be retro fitted to earlier models... They also modified the vent pipe with a cuff to the water feed pipe to help any freeze in that pipe, as a blocked vent can cause engine crankcase  back pressure , with results of engine oil seals and tach drive leaks......