inputs.text: excellent - far toasty min max thermometer placed inside engine compartment chaparral h2o sport 18 ft also custom made cover marooned check times week far temp not dropped 51 degrees inside compartment thanks heater outside dropped 32 degrees get colder heater protect like year round use update temp gotten extremely cold wind chill 2 degrees two nights ago not much better entire week cold weather gusty winds snow course ice checked boat daily temp engine compartment 41 42 degrees like mentioned min max thermometer one prong besides heater behind coolest area heater supposed couldnt happier not use space heaters dangerous not considered winterizing boat heater proper heater insurance not cover loss