We have a large thermometer secured to wall in the front stall of the trailer. The current temperature is visible from the truck using our trailer camera system. We can alter the ventilation in the trailer based on the temperature to keep the equine comfortable during transport.
WARM WEATHER CONSIDERATIONS: When are are transporting one equine in a box stall or two equines in our straight stalls, we not only open up the rear and side windows in their area but we also open the half-door above the side ramps for increased ventilation. We only do this when the equines we are transporting are secured behind the floor to ceiling stall doors. While hauling equines with the half-doors open, we always secure full-size mesh screens over the openings which will allow air to flow through but will prevent any debris, birds, cigarettes from passing vehicles, and other hazards from entering the trailer. Due to safety concerns, we never haul with the half-doors open, with or without screens, when there is an equine in the front box stall or slant stall.
In addition to the three 12-volt fans that were installed in the trailer when we purchased it, we have added four small Ryobi 18-volt fans, two in each stall area, which are all turned on when we are transporting. We also carry a large 18-inch Ryobi fan which we secure to the box stall door in the vacant stall area when hauling a single equine. The Ryobi fans are operated by 18-volt rechargeable batteries which we switch out at fuel stops to provide the fans continuous power. We carry approximately a dozen batteries as well as a 12-volt battery charger that we plug into the truck for charging batteries on the go. The Ryobi fans will operate from 2-4 hours on a single battery depending on the fan speed and size of the battery. These fans really circulate the air and make a difference in the equines comfort level during transport.
COLD WEATHER CONSIDERATIONS: Our trailer is fully insulated and will maintain a comfortable temperature inside even when the temperature outside is freezing. When we are transporting equines during the colder weather months, we prefer not to have the equines blanketed unless they are body clipped. An equine can generate enough body heat to actually increase the temperature in the trailer if the windows and vents remain closed, or barely cracked, during transport. When there is more than one equine, the temperature inside the trailer can be several degrees higher than the outside temperature and a little balmy. It is not safe for a person to enter the stall with an equine to remove a blanket should the temperature inside the trailer become warm enough to warrant removal... a trailer stall is a confined space and it is always smart to limit the amount of time spent in that space with a prey animal with fight or flight instinct and truly unpredictable behavior. We would prefer that an equine be slightly chilly versus being overheated, therefore we recommend that they do not wear medium or heavy blankets during transport. If an equine must were a blanket, due to being body clipped or whatever reason, we recommend the blanket be lightweight or a stall / turnout sheet of some kind. We will haul with the windows and roof vents almost closed to reduce the amount of breeze through the trailer and limit the amount of heat loss inside the trailer. As the transport progresses and the temperature rises, we will gradually open the windows and roof vents at each fuel or rest stop. If necessary, we will be glad to blanket the equines in our care during layover stops.