Maximum temperature for special use heating to 160F with good delta T

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Hello community, First let me say thank you for any help you can throw my way - my hot water heating experience is in infancy and I will require time & experienced folks like yourselves to "show me the way". So, thank you for answering my beginner's question. My situation is still in the planning stages, so I'm all ears as far as if this is a good use of hot water boiler, if it's reasonably achievable, or any other input you might have.

I'd like to potentially use a hot water boiler in order to heat-treat firewood. I have an idea to use fanned heat exchangers in a 10ft x 10ft x 6ft room. The room is well insulated with polyiso foam insulation, including foil faced insulation on the ceiling. I would have the fanned heat exchangers on 2 walls facing one another, with metal IBC style totes of stacked, split firewood resting in between them. There would be anywhere from 2 or possibly 4 totes of firewood in the room at any given heating session, each tote containing between 800-1000lbs of firewood.

Needfully, the hot water heat running thru the heat exchangers will be enough to heat the cut & split firewood to a minimum internal temperature of 160F for a minimum time period of over an hour. I have sourced a used 96K BTU Burnham 204 LP hot water boiler as well as some ordinary copper tube / aluminum fin heat exchangers, as well as some high-heat automotive radiator fans (and will include some high temperature fan wiring). I will also source a high-temp room thermostat that will be used to turn on/off the boiler as needed to avoid any overheating in order to protect the insulation. The boiler would be located in an adjacent "room" that is separate from the heating chamber and the piping runs will be very short - probably 30ft overall not including the heat exchangers. Note that this room and the external "room" I have framed for the boiler will not be climate controlled, and will experience freezing temperatures. I assume, but need clarification if, the LP boiler can accommodate periods of freezing temperatures with the proper precautions. Would this include treating the water loops with antifreeze - and what else?

Realizing that an LP boiler in a non-climate controlled room may be less than ideal, I can of course explore a wood fired hot water boiler - I have plenty of firewood, after all :) But I was thinking that the LP boiler would be ideal especially with the ease of running it off a thermostat.

What I'm trying to work out is: can a hot water boiler get hot enough for effective heat transfer both in terms of efficiency and time? I see that the boiler I have has a maximum water temperature of 250F. While I don't expect to be able to run the water that hot, one of my questions is: How high can I crank the water temperature to be safe and within reason allow maximum Delta T thru the heat exchangers and into the wood? Can I expect temps of 200F or 210F perhaps? I don't think that an ordinary boiler water temp of 180F will provide enough Delta T to heat the wood in a reasonable time, nor am I sure that a small room temp of 160F can be achieved at all given a Delta T of only 20F. So in general: can I achieve a delta T of 40F or 50F in order to provide a much faster and certain 160F wood temperature?

Also of note, I don't think pex can handle this high of water temperature, so what other piping options would be appropriate? Lastly, I will of course seek professional help to install this system. I'm not trying to learn how to install a system like this over the internet, but I am trying to gauge if my heating idea is feasible and achievable.

Thank you very much for any input you have!
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