Electricity issue? TV blacking out when the heater is on.

If your rig has an energy management system, it's possible that the system is "shedding load" when the heater is running - in other words, turning off lower-priority circuits to keep the total current below the EMS maximums.

On our rig, for example, running the microwave or toaster oven will shut down the bedroom air conditioner or space heater, depending on the time of year. Once that extra load is removed, the shed circuits come alive again.

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