For background, my build thread is: http://www.skoolie.net/forums/f32/mi...-a-17040.html]
I know its summer and most folks are not thinking about heaters. However; winter is not far off and I have not yet done anything about house warmth. So, I had better start thinking about it…
I was initially thinking of building a diesel hydronic system. I like the diesel hydronic approach as I have plenty of diesel, it creates warm water for the house, could warm the engine (when desired), and when operating, the engine provides warm coolant to warm the house. However; the thought of buying and installing the additional components of this system (heat exchangers, fans, tubing, coolant pump, connectors, coolant, etc.), running all that plumbing, and getting it to work right is less exciting. Without much scrounging, it seems like it would be fairly easy to spend $1,000 just on the heat exchangers. I'm not sure yet if it is a positive or negative but the coach already has engine coolant lines running the full length so they could likely to tapped into and used. As soon as I remove the bus air conditioning condensers, I have a perfect spot for a diesel heater and generator (vented to the outside).
Then I got to thinking about the diesel air heaters (that heat air instead of coolant/anti-freeze). It seems that two of the diesel air heaters would be less total work and easily creates a two-zone system. I would need to run diesel fuel lines and DC power. Installation would be in the bus basement (dumping the exhaust outside) and two-three air ducts. Seems VERY simple!
I should note that I am not positive that either a 12Kw diesel hydronic heater or two 5Kw diesel air heaters are sufficient for my needs - but I think so. In theory, a poorly insulated house matching the coach's interior size requires 44k BTU (13Kw) to achieve a 50 degree temperature increase. I always winter in semi-warm locations where overnight lows are occasionally around freezing and day time highs in the 50's. I tend to keep house temp at about 60 degrees but am happy with 50 degrees overnight (no women to please, ever). 12Kw is approximately 41k BTU, 10Kw is approximately 34k BTU. So, I think either of these two options are sufficient - but perhaps marginally so. Adding a third diesel air heater at a later date would be easy, adding another diesel hydronic heater - less easy, I think.
I have been watching the hydronic threads and searched the forums for info (and did find some).
What am I missing? Do you have positive or negative experience with either approach? Am I over/under estimating the complexity of something?