I have a hot water reheat coil that I pulled out many years ago and have been saving it thinking that I may use it someday. Some day is now here. I have a crawl space area that I am thinking about using this in with a small fan, Domestic pump, aquastat remote bulb space stat, relay and control valve all of which I own already (except the pump). The coil is 16 x 20 with 2 rows of tubes. 10 tubes/row 1/2" tubes. I am thinking of using the how water from the tank which runs about 120° to 130°F. Any thoughts on the btuh capacity I can get out of this coil at these temps. I am not sure of cfm I will get out of the small fan that I have attached. The application is not critical it is just for tempering the space. The kitchen is above and the floor is cold when we reach ambient of about 20°. Control scheme is pretty simple,Call for heat starts pump, aquastat starts fan. Satisfied stops pump, aquastat stops fan. Crawl space has a heat run already so freezing is not an issue. Main question is BTUH of coil. I have no idea how to calculate this. Just want to see if the effort is worth it.