Because the heater block is adjacent to the
throttle spindle, some heat is also transferred through the spindle to the
butterfly, to prevent a thick build up of ice on the butterfly, which with
the type of carb used, can be a cause of rough running and possible engine
Because there is no significant heating of the intake air when hot
coolant is circulating through the carb heater blocks, there will be a
negligible loss of full engine power.
A suitable tap and additional tubing
(so that the pipe work can be extended to fit the tap in the cockpit) is
available as an optional extra. An optional digital temperature gauge is
available, this monitors the temp of one of the heater blocks closest to
the carb throttle spindle.
Extensive testing of the system has been
carried out during an English winter, and it has been demonstrated that
the system will prevent the formation of ice, and will also clear an ice
build-up if the optional tap is turned on after the engine begins to run
roughly due to ice formation.
The system has not been tested under all possible conditions that may
prevail, therefore its effectiveness cannot be guaranteed in all
circumstances. Aircraft equipped with this device should never be flown in
circumstances where a successful 'no power' landing cannot be made in the
event of engine failure.