How a refrigeration unit operates on a round depends on the vehicle, unit, product and load arrangement. Pre-chilled goods or insulated containers alone do not authorise switching the unit off; temperature outcomes and maker instructions also matter.
Get written guidance from the unit maker on permitted operation, power supply while parked or charging, and operating limits. Record vehicle and unit models. If the transport procedure requires the unit to remain on, do not change it.
On a route trial, time-stamp product loading and delivery temperatures, body air, unit state, door openings, waits, ambient conditions and load. For passive cooling, record container ID, cold-source type and conditioning. Place sensors according to the measurement plan; change one condition at a time.
Assess results against product acceptance conditions and authorised procedures; an air sensor does not replace product-core measurement. If a limit is exceeded, the designated responsible person decides whether to stop dispatch, restart the unit or hold the product. A result on one route does not guarantee performance for other products or weather.
