I have an Englander Stove Works add-on wood furnace (Model 28-3500) piped into the side of the plenum of my oil furnace in such a way that the hot air is blowing directly on a portion of the AC coil. I couldnít mount the pipe any higher so as to totally avoid the coil because immediately above the main trunk branches off of the plenum. I decided it wouldnít be wise to pipe into the trunk line because I thought it might starve two rooms of heat since the registers of those rooms are piped directly into the plenum.
The installation passed inspection just fine and the building inspector did not seem to have any issues with the input of the add-on being so close to the AC coil. The inspection basically concentrated on the safety aspects of the installation. I exceeded all minimum clearances by a wide margin and used all non-combustible materials (masonry) in critical areas, so once he saw that he was satisfied. However, now I'm learning that this may cause a problem and could overheat the coil causing abnormally high pressures in the system. Iím wondering whether or not to move the pipe somehow (not sure how yet) because of potential issues with the AC coil. However, Iím also wondering if it will cause any damage because my oil unit blows hot air directly THROUGH the coil anyway. Is the air coming out of my add-on that much hotter? I suppose I could test it if I had the right tools but I currently donít. Anyway, I was just wondering if anyone could give me some guidance since I donít want to have saved a bunch of money on heating oil through the winter only to have to spend it on a new coil this summer. Iíve only been burning (overnight for about 8 hours at a clip mostly) for a week so far-would that be enough to cook the coil?