Axeman Anderson upgrade from tri burner space heater

First of all I would like to say that this forum and its members are nothing short of awesome.
Several years ago I began heating with a Alaska stoker Stove II to help with heat cost in my electric home (this forum gave me the knowledge and confidence to take on the challenge). Just running in basement with one heat run to the center of house did well down to 15 degrees then the electric base boards had to run. Two years later I installed a Leisure Line Hyfire II (twin burner) in its place and it has made a big difference. My house is 1650 SQ FT ranch. I like that the tri burner is nearly trouble free and can be idled down without issue. I don't like the current set up because it is dirty and does'nt do a great job heating uniformly due to the lack of air moving system. I am in the process of installing central air so I will have duct work although I didn't want to use a heat exchanger with the air system.
I want to install a coal boiler system and start off small and add heating applications as I go.
I have an Axeman Anderson 130 I would like to install along with pex under the living space and using the domestic HW coil. I eventually want to heat my 800 sq ft garage and possibly 2 garages totaling 2000 sq ft at a distance of about 250 ft from my house. (I am working on buying a AA 260 if I need the added BTU capacity in the future).
My question is:
Will the AA 130 be too large to heat just my 1650 ft ranch running all year here is west central PA?
Can this system be used with PEX? I have read that the higher heat is not recommended with pex.
I fell in love with the Axeman Anderson design and was glad to be able to find one in excellent working order. I am looking for advice on how to proceed.
If anyone can offer some direction and suggestions I would greatly appreciate the help.
Thank you,
Mark

I heat 1800 sq' ranch with the axeman 130. I'm in the south east pa. area. The house has the origional windows form the 1960's w/storm windows,also heat my domestic water and a modine for the 2 car garage. The 130 keeps up no problem. I would think a 260 would be WAY OVERKILL for the house. As far as the garages you want to add, do you want to keep them at 70 ? Insulate the garage well .

I too have an AA130.

I haven't used any PEX...YET...but, I intend to as I expand my system sometime soon.

It is not so uncommon for my AA130 to pump water at temps above 200* due to overshoots, and that is a concern w/ PEX.

As I have been accumulating parts for this future endeavor, I did picked up a couple thermostatic mixing valves for cheap and will plumb them in to tame any temp spikes.

And besides myself, I know *AA130Fireman* uses a Air to Water heat exchanger Coil in a forced air systems.

You do not want to send 200+ degree water through pex tubing. Pipe the boiler primary/secondary and protect the zones with pex with mixing valves.

An AA130 is a nice unit, it should have enough capacity for your house and garage.