There is provided a heated livestock waterer having a heater chamber, a heaterdisposed in the heater chamber that, in operation, generates at least heatedgas, and a waterreservoir having at least one sidewall that is in thermal communication withthe heaterchamber, the water reservoir having an animal watering section and a coveredsection coveredby a lid, the lid and the covered section defining an air space that is influid communicationwith the heater chamber via an air passage, the air space having a vent toatmosphere.
