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 130F. 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.