Design a new system for existing shop.

rcrboy

I bought a home with a 36' D x 40'W x 14' H shop. The five loops of tubing was already installed and coiled up on the wall. The shop has R19 walls and R30 ceiling. I am looking for some guidance on putting together a boiler and all the necessary components. My first question is can I use a Navein boiler? And also what is the simplest system I can use? Thanks

GroundUp

The simplest is to buy a prefabricated system that's been designed and assembled by a professional. You absolutely can use a Navien boiler if you'd like, though they're not well liked by anybody who's ever had to service one. This isn't really the kind of thing that should be attempted without at least some sort of professional intervention, which will likely cost you a few bucks upfront but will save a whole lot more in the long run.

hot_rod

is there a good layer of insulation under the slab? Any idea on loop lengths.

1440 sq ft at a guesstimate 20 btu/ foot would be, 28,800 btu/ hr.

Cheap and easy but not high efficiency would be a gas or lp tank water heater. Tank, mix valve, pump air sep and expansion, it would be a simple build.