Running a boilermate off of the hot water coil

This is where all my hot water comes from in the winter. I just tied my coils into my boiler, which I had already hooked up to the Boilermate years prior. Works excellent, provided there isn't a call for heat on another zone. In that case it usually sucks enough heat out of the unit to make the burner fire.

Handfired stove here, but same principle.