All of the crew on board the paddle steamer have their first aid certficates, meaning they are all qualified to use the defibrillator that arrived two weeks ago.
The AED does not stay on board, but will have limited use to the wider public.
"We bring it into the office when we're not sailing, so it's sitting in here with me right now," Ms Petherick said.
"If someone rushed in to use it, we certainly wouldn't deny them the use of it, but it's difficult to advertise that we have it here, as it's only here when the boat's not sailing."
Directors of Heart Saver New Zealand Mike and Helen Mander wrote in a letter to Ms Petherick: "You strike us as being a very deserving recipient and we hope that the Heart Saver AED7000 serves your community well.
"We truly hope that you never have to use it, but at least you know you have one on hand in case of emergency."