We leave ours on during the season when we are not there. We tend to cook meals at home and freeze them. We then put them in the front boot of the car (basically under the bonnet but is electric so no engine) which stays very cool for journey down there. Then straight in the freezer when we arrive.
If we turned it off we'd have to wait for the freezer to get down to temperature which would be annoying.
When we turn down the van for winter it get's turned off, cleaned and dried and doors left ajar so it has air circulation.
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