The link at the bottom is the only cng heater for vehicle cab heating that I have seen. They don't have a us distributer, and when you try to get more info, you're ignored. There has to be another source.
As far as a cng source is concerned, there are filling stations in lots of places so I don't think that a fuel source is an issue.
I had always intended to find a unit with a heat exchanger. Poisonous air and moisture would both be discharged away from any person in the vehicle.
I don't think that I'm trying to reinvent the wheel. But I am trying to use as little crude as I can. It's expensive, and pollutes. Using any energy from the battery doesn't make sense to me if there is another way.
I do appreciate the coments and hope that they don't stop.
http://www.trumauk.com/images/librar...res/Trucks.pdf