[Hawley]

These units are manufacturers of warm air furnaces. They do not make hot water. The efficiency that you mention is a snap shot of the operation of the oil burner when the unit was tested. I too have been in the business for over forty years. If you decide to replace the boiler have your contractor quote any cast iron, wet base American made boiler. I be glad to answer any other heating or hot water questions. Enjoy the day and be safe.