Installing a combi boiler with OWB without storage (pic)

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New Member
Jan 31, 2023
Wondering if I could get some advice please, I'm installing a combi boiler for a small cabin I'm building for myself.
I would like to tie my Outdoor wood stove into it as my primary source for heat and still use the combi with propane for my DHW.
I would like to use the LP side of the combi fall, and spring heating.
This is a slap radiant floor.

This is currently where I'm at, from what I've researched it's best to have a storage for the OWB but that's not an option as I don't have the room.
Was planning on using a plate exchanger with a mixing valve and tying into the tees on the supply and return.

I guess I don't want to go any further until I know what will work and what won't.
In the photo you can see where I'm currently at, the supply is soldered up, but the return is what you see.

Please let me know your thought how I should proceed.

Thank you much.

Installing a combi boiler with OWB without storage (pic)
I plumbed in an oil and wood boiler back in 1985, the system did not work very good. I was put onto caleffi idronics. I have all their journals of design innovation for hot water heating. These journals are also on line. I don't remember how to access them. You can learn a lot by looking at them. I tore out my entire system in the mech room in 2018 and replumbed it the way idronics #10 page 29 suggested. The system works great now. I plumbed all black pipe. I varied some from the book because I did not have the room for all the piping. I did not do in floor heat so mine does not look like what you are asking for. look at these books you will see correctly how to finish your job.