The rear refractory panel in my zero-clearance fireplace sustained normal wear and tear damage due to years of fireplace use. After scouring the internet for a replacement panel for this particular fireplace, I discovered that the fireplace manufacturer of my fireplace had gone out a business. This is not uncommon for older fireplaces.
I checked around in my town and couldn't find any fireplace store who had replacement panels. I asked the chimney sweep who cleans my chimney and he told me that needed to get replacement panels and that he would cut and install them for me. My fireplace has a back, two side, and a floor panel. Four total panels. I only had damage to the back panel. After surfing the internet I stumbled across what I thought was the best deal for these replacement panels at e-Fireplace Store.com. I sent them a few emails and made a call or two and decided that the best deal for me was to order their 24X40 set of 2 panels. I planned to have my chimney sweep guy cut what I needed for this job and save the leftovers for any future replacement. There's free shipping on the set of 2 panels, which is a "significant" savings on the cost.
I ordered the panels and it took about 2-3 weeks to receive them. That seemed a bit long, but I suppose they make the panels once they're ordered. The panels arrived in an 18 wheeler truck, so plan to have an 18 wheeler in your driveway, or if that won't work as it didn't for me (I live very rural and up a long narrow driveway), be prepared to have the driver meet you somewhere, and bring your pickup truck. The panels were expertly packed on a pallet. As packed, they're pretty heavy. Be careful once they arrive because these panels are fragile. They will break. Take the damaged panels out of your fireplace and use them as your cutting template. The old panels are probably held in with clips. Mine were. It took my fireplace guy about 15 minutes to do the entire operation. He used a "diamond blade" on his saw to cut the panels. It worked good. Do NOT use a standard saw blade.
Once installed, don't light a full fire to your fireplace. New panels must first cure and expand to the heat gently before they're completely ready for a fire. This takes about three hours. I used one of those match-lit logs you can buy at any Walmart. They don't produce extensive heat, they burn for about three hours, and they're easy to monitor. Once that part's complete, fire away. I'd also be careful not to over burn the first time. In other words, keep your wood OFF the panels and don't light a bonfire to your fireplace.
All in all I'm very happy about these panels. The eFireplaceStore.com folks will replace them if they arrive damaged, and mine refract the heat as designed and has been durable up to now. We've been using the fireplace daily for about a month since we had the back panel installed, with no deficiencies noted. I suppose the only downside to buying refractory replacements is the cost. They're not inexpensive, but they're worth the expense if you rely on your fireplace to provide heat during the winter months. I rate eFireplaceStore.com and these panels with an "A" and would not hesitate to recommend this product to a friend. Good luck!