Thanks Brent. Cool Pics of the pool build and then the solar install. How much was the solar install and all? And Aquatherm, is it in Sunrise, FL. I will check on that. I did get my equipment pad to be extended for the possible heater. So my PB is now doing a pad of 3 x 7. Should be enough. I hope. Or is that too big. I can't go 4 x 6 because my silly walkway on side of house between my house wall and fence is only five feet wide. So he thought going with 3 x 5, which is what he needed with a bit extra. I think 7 should be plenty. 3 x 7 pad. Do the solar panels need pad or is it just wall space. My pool continuation work started yesterday. SO exciting to finally see it come back up to a change. This is my pool in October after my first pool builder left my site, (went bankrupt, and took my payments. Long, Horrible, Story). Now my new pool builder started yesterday and wow. They got all the excation done, limerock, and sand down and compacted. Today they are doing the pavers lay down (while I'm at work). I'll try to upload a picture of that. They are awesome. Great people. They promised and delivered. I'm so not used to that. Plus very kind with my requests like the concrete pad extended. (Thanks to you guys and your thoughts). Now if I can only think of any more requests. Anything else I should ask or check on.??? Like my Sunshelf. Did I ruin it by putting it on the second shelf. They mentioned that the bubbler won't really do any effect. And maybe I could turn that bubbler line to a return line. Any thoughts. Or should I just leave as a bubbler and do a rigged job afterwards to make it bubble. Confused.

The wall there is partly garage which is unheated and (probably) uninsulated and partly (where the windows are) a chunk of garage that was carved out during construction to serve as a potting room with an open doorway. It's a little weird. Anyway, it's not quite the same as your friend is proposing. It has ceiling vents (which are stuck in the open position) for ventilation and looks like it was a pretty nice kit when installed, although it's just single-paned glass. I'm not sure I would have chosen to install it like that, though. It's slightly higher than the roof and presented a challenge for the roofer. Once we try growing things in there and using water in it we'll have a better idea of the humidity. I'm hoping it'll be more like a sunroom or enclosed porch than a swampy hothouse. I'm looking forward to cleaning it up after the earthquake. No wimpy acrylic ceiling glass here! :P (Don't let your friend put glass over his head--you guys are due too!)

Wow, thanks for all the wonderful responses. Seems like reality is raining on my parade a bit. But there's lots of great information here. As akamainegrower suspects, the chimney is not one of those big chimneys--it's only about 3' by 3'. Technically there is a second chimney at the back of the house as well, but that begins where the kitchen is (and I think the kitchen has always been in the same spot) so perhaps that second one was for an old kitchen stove? I'm intrigued a bit by the gas appliance possibilities--although I love a wood fire, gas seems like it might be more possible. A wood stove would be a great option, but unfortunately our rooms are fairly small and I can't really picture any spot where a wood stove could fit if it were standing out from the wall. There's really only space for something that fits into an existing cavity. However, there may be space next to the existing chimney. I seem to recall that, years ago, I heard of some kind of fireplace system that could be installed with some kind of pipe chimney instead of a masonry chimney? Meaning it could more easily be retrofitted to run up the interior of a house? Perhaps I'm completely misremembering. DK and Sons, thanks for the top about the recommended annual inspection. I hadn't realized these were recommended even where the chimney is not used for a fireplace. I'll have to look into that, and check whether this company is reputable or what the work usually costs in my area.

First of all, you’ve received some excellent advice and I’m not pretending for one second to be remotely as knowledgeable on the subject as people like Jake, but since the possibility exists of potentially doing additional work in order to satisfy current IRC or California earthquake building code or plumbing code or whatever authority has jurisdiction over your situation (I realize I’m taking liberties with these terms), does the location of your unit meet the minimum clearance requirements vis-à-vis ease of serviceability? From your photo and your description, it might not. (I know that the air handler for a heat pump I had installed during an attic conversion/remodel circa 2000 sure doesn’t!) I don’t know off the top of my head what’s applicable in your case, but it’s something to take into consideration and, if found to be inadequate, might as well be taken care of at the same time as the rest of the mods. Oh, and fwiw, I have two Rheem tankless systems (NG, outside install) that have provided trouble-free service for many years, now. Of course, now that I’ve said that, they’ll both fail within a week... :/