I've been using one of the Taylor's heaters for the past 3 months living onboard during a
winter in
Sydney (Australia). Great bit of kit, keeps the place (36 footer) nice and warm. Full tank lasts forever. Must measure the
exhaust diameter but it can't be much over one inch. And it looks pretty good too! I believe they are a bit expensive new but well worth it, mine is 20 years old and apart from a few new burners over the years is still going strong.