A:Answer Hi Joe - We are sorry to hear your microwave is not heating and appreciate your loyalty! While the venting is the same, when replacing an over-the-range microwave, the mounting bracket included with the new microwave should be used since the mounting bracket is specific to each model. The new screws, bolts, and exhaust adapter should also be used. Also, if installed for recirculating (non-vent), Charcoal Filter JX81L is included. Check out the Installation Instructions online: https://products.geappliances.com/MarketingObjectRetrieval/Dispatcher?RequestType=PDF&Name=49-40675-4.PDF - Enjoy! Sue