Hello Customer support, on your website I saw a similar coil to mine shown in the photo. It looks like the 190 series. We have 2 coils as shown in the pic, one is stamped 740 the other 840. Your site has the 740 but not the 840. How can we find the 840? Is there a special tool to replace these coils? Does the stamped code exactly identify the product or do I need to measure the length of the coil? We have another size window, so that window will probably have different coil codes, correct? Also, we can just replace the coils, correct? If needed, are the plastic parts available? Thanks for your time in answering all our questions, this is new to us, Mary
