Heathcoat Hall, Wellbrook Street, Tiverton is shown by the green arrow in the map below, courtesy of Google Maps UK (TM).
There two convenient 'Pay and Display' car parks. One is just South of Angel Hill on the river side of the road. It has 47 places. The other is in Wellbrook Street itself, squashed between Church Street and Leat steet and must be entered from the one way system. It has 27 spaces.
There is some close on-street parking in Church Street, in Wellbrook Street, in King Street and surrounding streets.