Getting into a basketcase...

I'm in the process of buying a property with a few year old Central Boiler (I assume it is a classic model) wood boiler. The property is a closed down horse boarding facility. The boiler is currently not hooked up (and looks barely used) because the previous owners could not figure out how to regulate temperatures well and gave up on it. The property is a 105ftx60ft building with living quarters in it. I am planning on turning it into a shop and using roughly 1800sq ft for living/office area and the remaining space as the shop.

From what I can tell, there look to be at least 2 Modine heat exchangers for heating the shop area (one has a squirrel cage fan and the other is a standard fan). The current furnace for the living quarters is kind of a hacked up setup because the previous owners were never happy with heating and is best described as a basket case, but it does look like there is a forced are heat exchanger for heating the living area in the rafters of the building. There is also a large electric water heater 100-150gal that has a water to water heat exchanger on it that isn't hooked up.

I'm assuming why they had problems is that the boiler was sized for the entire building and they were using one pump off the boiler and splitting it for heating the former stable area and apartment. I'm not sure if I want to heat the living/office area with the boiler or just the shop area, but from my research it seems like what would help regulate the heat output of this system would be to add some extra storage to it. And run separate "zones" to the different areas rather than trying to heat the whole thing uniformly.

I am open to any suggestions from your experiences.

I would like to heat the living area with it eventually, but I want a back up heating system in there because we will probably be going back and forth to this property (because it needs a lot of work) this winter so I need some other way, either propane or electric to heat the areas with water pipes while we are gone so nothing freezes. I know they make a propane boiler, even Central Boiler has a propane backup/clean burn attachment for their boilers that I assume could be retrofitted to the unit.

As far as lines go it's a weird set-up like I said...for one, the boiler is probably only 6 feet away from the building. It has large copper lines running exposed from the unit into the side of the building. The lines once in the wall run 90 deg straight up the uninsulated wall section and near the top of the wall is the valving that splits the flow to the various areas. That piping looks to be the green type that central boiler sells that connects with the brass fittings. The copper lines running exposed outside have threaded disconnects about halfway and they are disconnected, the lines running from the distribution valve are also disconnected.

This building was built in 2005/2006 and it amazes me how poorly it was taken care of, but I got it for a deal because of that and I have the skills to repair most of it. So I know I will come out well ahead of building something new.

As far as firing it up to test, can I run straight water in it to test. If it passes, what type of antifreeze should I put into the system?

Edit: The water in this area is extremely hard/mineral rich